⬆️ rust-analyzer

.github/workflows/ci.yaml

@@ -101,7 +101,7 @@ jobs:
     - name: Install Nodejs
       uses: actions/setup-node@v1
       with:
-        node-version: 14.x
+        node-version: 16.x
 
     - name: Install xvfb
       if: matrix.os == 'ubuntu-latest'

.github/workflows/release.yaml

@@ -68,7 +68,7 @@ jobs:
       - name: Install Node.js
         uses: actions/setup-node@v1
         with:
-          node-version: 14.x
+          node-version: 16.x
 
       - name: Update apt repositories
         if: matrix.target == 'aarch64-unknown-linux-gnu' || matrix.target == 'arm-unknown-linux-gnueabihf'
@@ -133,7 +133,7 @@ jobs:
     container:
       image: rust:alpine
       volumes:
-        - /usr/local/cargo/registry
+        - /usr/local/cargo/registry:/usr/local/cargo/registry
 
     steps:
       - name: Install dependencies
@@ -176,7 +176,7 @@ jobs:
       - name: Install Nodejs
         uses: actions/setup-node@v1
         with:
-          node-version: 14.x
+          node-version: 16.x
 
       - run: echo "TAG=$(date --iso -u)" >> $GITHUB_ENV
         if: github.ref == 'refs/heads/release'
@@ -253,9 +253,9 @@ jobs:
       - name: Publish Extension (Code Marketplace, nightly)
         if: github.ref != 'refs/heads/release' && (github.repository == 'rust-analyzer/rust-analyzer' || github.repository == 'rust-lang/rust-analyzer')
         working-directory: ./editors/code
-        run: npx vsce publish --pat ${{ secrets.MARKETPLACE_TOKEN }} --packagePath ../../dist/rust-analyzer-*.vsix --pre-release
+        run: npx vsce publish --pat ${{ secrets.MARKETPLACE_TOKEN }} --packagePath ../../dist/rust-analyzer-*.vsix
 
       - name: Publish Extension (OpenVSX, nightly)
         if: github.ref != 'refs/heads/release' && (github.repository == 'rust-analyzer/rust-analyzer' || github.repository == 'rust-lang/rust-analyzer')
         working-directory: ./editors/code
-        run: npx ovsx publish --pat ${{ secrets.OPENVSX_TOKEN }} --packagePath ../../dist/rust-analyzer-*.vsix --pre-release
+        run: npx ovsx publish --pat ${{ secrets.OPENVSX_TOKEN }} --packagePath ../../dist/rust-analyzer-*.vsix

.vscode/launch.json

@@ -78,7 +78,7 @@
       "request": "launch",
       "runtimeExecutable": "${execPath}",
       "args": [
-        "--disable-extension", "matklad.rust-analyzer",
+        "--disable-extension", "rust-lang.rust-analyzer",
         "--extensionDevelopmentPath=${workspaceFolder}/editors/code"
       ],
       "outFiles": [

Cargo.lock

@@ -710,6 +710,7 @@ dependencies = [
  "ide-db",
  "itertools",
  "profile",
+ "serde_json",
  "sourcegen",
  "stdx",
  "syntax",

crates/base-db/src/input.rs

@@ -6,7 +6,7 @@
 //! actual IO. See `vfs` and `project_model` in the `rust-analyzer` crate for how
 //! actual IO is done and lowered to input.
 
-use std::{fmt, iter::FromIterator, ops, panic::RefUnwindSafe, str::FromStr, sync::Arc};
+use std::{fmt, ops, panic::RefUnwindSafe, str::FromStr, sync::Arc};
 
 use cfg::CfgOptions;
 use rustc_hash::{FxHashMap, FxHashSet};

crates/hir-def/src/macro_expansion_tests/builtin_fn_macro.rs

@@ -295,13 +295,13 @@ fn test_concat_expand() {
 #[rustc_builtin_macro]
 macro_rules! concat {}
 
-fn main() { concat!("foo", "r", 0, r#"bar"#, "\n", false); }
+fn main() { concat!("foo", "r", 0, r#"bar"#, "\n", false, '"', '\0'); }
 "##,
         expect![[r##"
 #[rustc_builtin_macro]
 macro_rules! concat {}
 
-fn main() { "foor0bar\nfalse"; }
+fn main() { "foor0bar\nfalse\"\u{0}"; }
 "##]],
     );
 }

crates/hir-def/src/macro_expansion_tests/mbe.rs

@@ -885,7 +885,7 @@ macro_rules! m {
     ($t:ty) => ( fn bar() -> $ t {} )
 }
 
-fn bar() -> & 'a Baz<u8> {}
+fn bar() -> &'a Baz<u8> {}
 
 fn bar() -> extern "Rust"fn() -> Ret {}
 "#]],
@@ -1578,7 +1578,7 @@ macro_rules !register_methods {
             ($$($val: expr), *) = > {
                 struct Foo;
                 impl Foo {
-                    $(fn $method()-> & 'static[u32] {
+                    $(fn $method()-> &'static[u32] {
                         &[$$($$val), *]
                     }
                     )*
@@ -1591,10 +1591,10 @@ macro_rules !implement_methods {
     ($($val: expr), *) = > {
         struct Foo;
         impl Foo {
-            fn alpha()-> & 'static[u32] {
+            fn alpha()-> &'static[u32] {
                 &[$($val), *]
             }
-            fn beta()-> & 'static[u32] {
+            fn beta()-> &'static[u32] {
                 &[$($val), *]
             }
         }
@@ -1602,10 +1602,10 @@ macro_rules !implement_methods {
 }
 struct Foo;
 impl Foo {
-    fn alpha() -> & 'static[u32] {
+    fn alpha() -> &'static[u32] {
         &[1, 2, 3]
     }
-    fn beta() -> & 'static[u32] {
+    fn beta() -> &'static[u32] {
         &[1, 2, 3]
     }
 }

crates/hir-def/src/macro_expansion_tests/mbe/regression.rs

@@ -166,7 +166,7 @@ macro_rules! int_base {
     }
 }
 #[stable(feature = "rust1", since = "1.0.0")] impl fmt::Binary for isize {
-    fn fmt(&self , f: &mut fmt::Formatter< '_>) -> fmt::Result {
+    fn fmt(&self , f: &mut fmt::Formatter<'_>) -> fmt::Result {
         Binary.fmt_int(*self as usize, f)
     }
 }
@@ -724,7 +724,7 @@ macro_rules! delegate_impl {
         }
     }
 }
-impl <> Data for & 'amut G where G: Data {}
+impl <> Data for &'amut G where G: Data {}
 "##]],
     );
 }

crates/hir-def/src/macro_expansion_tests/mbe/tt_conversion.rs

@@ -78,7 +78,7 @@ m!(static bar: &'static str = "hello";);
 macro_rules! m {
     ($($t:tt)*) => { $($t)*}
 }
-static bar: & 'static str = "hello";
+static bar: &'static str = "hello";
 "#]],
     );
 }

crates/hir-def/src/macro_expansion_tests/proc_macros.rs

@@ -87,7 +87,7 @@ fn foo() { bar.; blub }
 fn foo() { bar.; blub }
 
 fn foo() {
-    bar. ;
+    bar.;
     blub
 }"##]],
     );

crates/hir-def/src/nameres/mod_resolution.rs

@@ -73,10 +73,12 @@ impl ModDir {
                 candidate_files.push(self.dir_path.join_attr(attr_path, self.root_non_dir_owner))
             }
             None if file_id.is_include_macro(db.upcast()) => {
+                let name = name.unescaped();
                 candidate_files.push(format!("{}.rs", name));
                 candidate_files.push(format!("{}/mod.rs", name));
             }
             None => {
+                let name = name.unescaped();
                 candidate_files.push(format!("{}{}.rs", self.dir_path.0, name));
                 candidate_files.push(format!("{}{}/mod.rs", self.dir_path.0, name));
             }

crates/hir-def/src/nameres/tests/mod_resolution.rs

@@ -132,9 +132,9 @@ pub struct Bar;
         expect![[r#"
             crate
             Bar: t v
-            async: t
+            r#async: t
 
-            crate::async
+            crate::r#async
             Bar: t v
         "#]],
     );

crates/hir-expand/src/builtin_fn_macro.rs

@@ -251,9 +251,13 @@ fn format_args_expand(
     }
     for arg in &mut args {
         // Remove `key =`.
-        if matches!(arg.token_trees.get(1), Some(tt::TokenTree::Leaf(tt::Leaf::Punct(p))) if p.char == '=' && p.spacing != tt::Spacing::Joint)
+        if matches!(arg.token_trees.get(1), Some(tt::TokenTree::Leaf(tt::Leaf::Punct(p))) if p.char == '=')
         {
-            arg.token_trees.drain(..2);
+            // but not with `==`
+            if !matches!(arg.token_trees.get(2), Some(tt::TokenTree::Leaf(tt::Leaf::Punct(p))) if p.char == '=' )
+            {
+                arg.token_trees.drain(..2);
+            }
         }
     }
     let _format_string = args.remove(0);
@@ -357,6 +361,12 @@ fn unquote_str(lit: &tt::Literal) -> Option<String> {
     token.value().map(|it| it.into_owned())
 }
 
+fn unquote_char(lit: &tt::Literal) -> Option<char> {
+    let lit = ast::make::tokens::literal(&lit.to_string());
+    let token = ast::Char::cast(lit)?;
+    token.value()
+}
+
 fn unquote_byte_string(lit: &tt::Literal) -> Option<Vec<u8>> {
     let lit = ast::make::tokens::literal(&lit.to_string());
     let token = ast::ByteString::cast(lit)?;
@@ -408,8 +418,12 @@ fn concat_expand(
                 // concat works with string and char literals, so remove any quotes.
                 // It also works with integer, float and boolean literals, so just use the rest
                 // as-is.
-                let component = unquote_str(it).unwrap_or_else(|| it.text.to_string());
-                text.push_str(&component);
+                if let Some(c) = unquote_char(it) {
+                    text.push(c);
+                } else {
+                    let component = unquote_str(it).unwrap_or_else(|| it.text.to_string());
+                    text.push_str(&component);
+                }
             }
             // handle boolean literals
             tt::TokenTree::Leaf(tt::Leaf::Ident(id))

crates/hir-expand/src/fixup.rs

@@ -67,7 +67,6 @@ pub(crate) fn fixup_syntax(node: &SyntaxNode) -> SyntaxFixups {
             preorder.skip_subtree();
             continue;
         }
-
         // In some other situations, we can fix things by just appending some tokens.
         let end_range = TextRange::empty(node.text_range().end());
         match_ast! {
@@ -194,7 +193,75 @@ pub(crate) fn fixup_syntax(node: &SyntaxNode) -> SyntaxFixups {
                     }
                 },
                 // FIXME: foo::
-                // FIXME: for, match etc.
+                ast::MatchExpr(it) => {
+                    if it.expr().is_none() {
+                        let match_token = match it.match_token() {
+                            Some(t) => t,
+                            None => continue
+                        };
+                        append.insert(match_token.into(), vec![
+                            SyntheticToken {
+                                kind: SyntaxKind::IDENT,
+                                text: "__ra_fixup".into(),
+                                range: end_range,
+                                id: EMPTY_ID
+                            },
+                        ]);
+                    }
+                    if it.match_arm_list().is_none() {
+                        // No match arms
+                        append.insert(node.clone().into(), vec![
+                            SyntheticToken {
+                                kind: SyntaxKind::L_CURLY,
+                                text: "{".into(),
+                                range: end_range,
+                                id: EMPTY_ID,
+                            },
+                            SyntheticToken {
+                                kind: SyntaxKind::R_CURLY,
+                                text: "}".into(),
+                                range: end_range,
+                                id: EMPTY_ID,
+                            },
+                        ]);
+                    }
+                },
+                ast::ForExpr(it) => {
+                    let for_token = match it.for_token() {
+                        Some(token) => token,
+                        None => continue
+                    };
+
+                    let [pat, in_token, iter] = [
+                        (SyntaxKind::UNDERSCORE, "_"),
+                        (SyntaxKind::IN_KW, "in"),
+                        (SyntaxKind::IDENT, "__ra_fixup")
+                    ].map(|(kind, text)| SyntheticToken { kind, text: text.into(), range: end_range, id: EMPTY_ID});
+
+                    if it.pat().is_none() && it.in_token().is_none() && it.iterable().is_none() {
+                        append.insert(for_token.into(), vec![pat, in_token, iter]);
+                    // does something funky -- see test case for_no_pat
+                    } else if it.pat().is_none() {
+                        append.insert(for_token.into(), vec![pat]);
+                    }
+
+                    if it.loop_body().is_none() {
+                        append.insert(node.clone().into(), vec![
+                            SyntheticToken {
+                                kind: SyntaxKind::L_CURLY,
+                                text: "{".into(),
+                                range: end_range,
+                                id: EMPTY_ID,
+                            },
+                            SyntheticToken {
+                                kind: SyntaxKind::R_CURLY,
+                                text: "}".into(),
+                                range: end_range,
+                                id: EMPTY_ID,
+                            },
+                        ]);
+                    }
+                },
                 _ => (),
             }
         }
@@ -287,6 +354,111 @@ mod tests {
         assert_eq!(tt.to_string(), original_as_tt.to_string());
     }
 
+    #[test]
+    fn just_for_token() {
+        check(
+            r#"
+fn foo() {
+    for
+}
+"#,
+            expect![[r#"
+fn foo () {for _ in __ra_fixup {}}
+"#]],
+        )
+    }
+
+    #[test]
+    fn for_no_iter_pattern() {
+        check(
+            r#"
+fn foo() {
+    for {}
+}
+"#,
+            expect![[r#"
+fn foo () {for _ in __ra_fixup {}}
+"#]],
+        )
+    }
+
+    #[test]
+    fn for_no_body() {
+        check(
+            r#"
+fn foo() {
+    for bar in qux
+}
+"#,
+            expect![[r#"
+fn foo () {for bar in qux {}}
+"#]],
+        )
+    }
+
+    // FIXME: https://github.com/rust-lang/rust-analyzer/pull/12937#discussion_r937633695
+    #[test]
+    fn for_no_pat() {
+        check(
+            r#"
+fn foo() {
+    for in qux {
+
+    }
+}
+"#,
+            expect![[r#"
+fn foo () {__ra_fixup}
+"#]],
+        )
+    }
+
+    #[test]
+    fn match_no_expr_no_arms() {
+        check(
+            r#"
+fn foo() {
+    match
+}
+"#,
+            expect![[r#"
+fn foo () {match __ra_fixup {}}
+"#]],
+        )
+    }
+
+    #[test]
+    fn match_expr_no_arms() {
+        check(
+            r#"
+fn foo() {
+    match x {
+
+    }
+}
+"#,
+            expect![[r#"
+fn foo () {match x {}}
+"#]],
+        )
+    }
+
+    #[test]
+    fn match_no_expr() {
+        check(
+            r#"
+fn foo() {
+    match {
+        _ => {}
+    }
+}
+"#,
+            expect![[r#"
+fn foo () {match __ra_fixup {}}
+"#]],
+        )
+    }
+
     #[test]
     fn incomplete_field_expr_1() {
         check(
@@ -296,7 +468,7 @@ fn foo() {
 }
 "#,
             expect![[r#"
-fn foo () {a . __ra_fixup}
+fn foo () {a .__ra_fixup}
 "#]],
         )
     }
@@ -306,11 +478,11 @@ fn foo () {a . __ra_fixup}
         check(
             r#"
 fn foo() {
-    a. ;
+    a.;
 }
 "#,
             expect![[r#"
-fn foo () {a . __ra_fixup ;}
+fn foo () {a .__ra_fixup ;}
 "#]],
         )
     }
@@ -320,12 +492,12 @@ fn foo () {a . __ra_fixup ;}
         check(
             r#"
 fn foo() {
-    a. ;
+    a.;
     bar();
 }
 "#,
             expect![[r#"
-fn foo () {a . __ra_fixup ; bar () ;}
+fn foo () {a .__ra_fixup ; bar () ;}
 "#]],
         )
     }
@@ -353,7 +525,7 @@ fn foo() {
 }
 "#,
             expect![[r#"
-fn foo () {let x = a . __ra_fixup ;}
+fn foo () {let x = a .__ra_fixup ;}
 "#]],
         )
     }
@@ -369,7 +541,7 @@ fn foo() {
 }
 "#,
             expect![[r#"
-fn foo () {a . b ; bar () ;}
+fn foo () {a .b ; bar () ;}
 "#]],
         )
     }

crates/hir-expand/src/mod_path.rs

@@ -22,7 +22,7 @@ pub struct ModPath {
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
-pub struct EscapedModPath<'a>(&'a ModPath);
+pub struct UnescapedModPath<'a>(&'a ModPath);
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub enum PathKind {
@@ -102,8 +102,8 @@ impl ModPath {
         }
     }
 
-    pub fn escaped(&self) -> EscapedModPath<'_> {
-        EscapedModPath(self)
+    pub fn unescaped(&self) -> UnescapedModPath<'_> {
+        UnescapedModPath(self)
     }
 
     fn _fmt(&self, f: &mut fmt::Formatter<'_>, escaped: bool) -> fmt::Result {
@@ -134,9 +134,9 @@ impl ModPath {
             }
             first_segment = false;
             if escaped {
-                segment.escaped().fmt(f)?
-            } else {
                 segment.fmt(f)?
+            } else {
+                segment.unescaped().fmt(f)?
             };
         }
         Ok(())
@@ -145,13 +145,13 @@ impl ModPath {
 
 impl Display for ModPath {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self._fmt(f, false)
+        self._fmt(f, true)
     }
 }
 
-impl<'a> Display for EscapedModPath<'a> {
+impl<'a> Display for UnescapedModPath<'a> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self.0._fmt(f, true)
+        self.0._fmt(f, false)
     }
 }
 

crates/hir-expand/src/name.rs

@@ -7,12 +7,16 @@ use syntax::{ast, SmolStr, SyntaxKind};
 /// `Name` is a wrapper around string, which is used in hir for both references
 /// and declarations. In theory, names should also carry hygiene info, but we are
 /// not there yet!
+///
+/// Note that `Name` holds and prints escaped name i.e. prefixed with "r#" when it
+/// is a raw identifier. Use [`unescaped()`][Name::unescaped] when you need the
+/// name without "r#".
 #[derive(Debug, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub struct Name(Repr);
 
-/// `EscapedName` will add a prefix "r#" to the wrapped `Name` when it is a raw identifier
+/// Wrapper of `Name` to print the name without "r#" even when it is a raw identifier.
 #[derive(Debug, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
-pub struct EscapedName<'a>(&'a Name);
+pub struct UnescapedName<'a>(&'a Name);
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
 enum Repr {
@@ -34,37 +38,26 @@ fn is_raw_identifier(name: &str) -> bool {
     is_keyword && !matches!(name, "self" | "crate" | "super" | "Self")
 }
 
-impl<'a> fmt::Display for EscapedName<'a> {
+impl<'a> fmt::Display for UnescapedName<'a> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match &self.0 .0 {
             Repr::Text(text) => {
-                if is_raw_identifier(text) {
-                    write!(f, "r#{}", &text)
-                } else {
-                    fmt::Display::fmt(&text, f)
-                }
+                let text = text.strip_prefix("r#").unwrap_or(text);
+                fmt::Display::fmt(&text, f)
             }
             Repr::TupleField(idx) => fmt::Display::fmt(&idx, f),
         }
     }
 }
 
-impl<'a> EscapedName<'a> {
-    pub fn is_escaped(&self) -> bool {
-        match &self.0 .0 {
-            Repr::Text(it) => is_raw_identifier(&it),
-            Repr::TupleField(_) => false,
-        }
-    }
-
-    /// Returns the textual representation of this name as a [`SmolStr`].
-    /// Prefer using this over [`ToString::to_string`] if possible as this conversion is cheaper in
-    /// the general case.
+impl<'a> UnescapedName<'a> {
+    /// Returns the textual representation of this name as a [`SmolStr`]. Prefer using this over
+    /// [`ToString::to_string`] if possible as this conversion is cheaper in the general case.
     pub fn to_smol_str(&self) -> SmolStr {
         match &self.0 .0 {
             Repr::Text(it) => {
-                if is_raw_identifier(&it) {
-                    SmolStr::from_iter(["r#", &it])
+                if let Some(stripped) = it.strip_prefix("r#") {
+                    SmolStr::new(stripped)
                 } else {
                     it.clone()
                 }
@@ -97,9 +90,11 @@ impl Name {
 
     /// Resolve a name from the text of token.
     fn resolve(raw_text: &str) -> Name {
+        // When `raw_text` starts with "r#" but the name does not coincide with any
+        // keyword, we never need the prefix so we strip it.
         match raw_text.strip_prefix("r#") {
-            Some(text) => Name::new_text(SmolStr::new(text)),
-            None => Name::new_text(raw_text.into()),
+            Some(text) if !is_raw_identifier(text) => Name::new_text(SmolStr::new(text)),
+            _ => Name::new_text(raw_text.into()),
         }
     }
 
@@ -142,8 +137,15 @@ impl Name {
         }
     }
 
-    pub fn escaped(&self) -> EscapedName<'_> {
-        EscapedName(self)
+    pub fn unescaped(&self) -> UnescapedName<'_> {
+        UnescapedName(self)
+    }
+
+    pub fn is_escaped(&self) -> bool {
+        match &self.0 {
+            Repr::Text(it) => it.starts_with("r#"),
+            Repr::TupleField(_) => false,
+        }
     }
 }
 

crates/hir-expand/src/quote.rs

@@ -196,8 +196,8 @@ impl_to_to_tokentrees! {
     tt::Literal => self { self };
     tt::Ident => self { self };
     tt::Punct => self { self };
-    &str => self { tt::Literal{text: format!("\"{}\"", self.escape_debug()).into(), id: tt::TokenId::unspecified()}};
-    String => self { tt::Literal{text: format!("\"{}\"", self.escape_debug()).into(), id: tt::TokenId::unspecified()}}
+    &str => self { tt::Literal{text: format!("\"{}\"", self.escape_default()).into(), id: tt::TokenId::unspecified()}};
+    String => self { tt::Literal{text: format!("\"{}\"", self.escape_default()).into(), id: tt::TokenId::unspecified()}}
 }
 
 #[cfg(test)]

crates/hir-ty/src/consteval.rs

@@ -2,7 +2,6 @@
 
 use std::{
     collections::HashMap,
-    convert::TryInto,
     fmt::{Display, Write},
 };
 

crates/hir-ty/src/infer/pat.rs

@@ -14,8 +14,9 @@ use crate::{
     consteval::intern_const_scalar,
     infer::{BindingMode, Expectation, InferenceContext, TypeMismatch},
     lower::lower_to_chalk_mutability,
-    static_lifetime, ConcreteConst, ConstValue, Interner, Substitution, Ty, TyBuilder, TyExt,
-    TyKind,
+    primitive::UintTy,
+    static_lifetime, ConcreteConst, ConstValue, Interner, Scalar, Substitution, Ty, TyBuilder,
+    TyExt, TyKind,
 };
 
 use super::PatLike;
@@ -294,7 +295,29 @@ impl<'a> InferenceContext<'a> {
                 let start_ty = self.infer_expr(*start, &Expectation::has_type(expected.clone()));
                 self.infer_expr(*end, &Expectation::has_type(start_ty))
             }
-            Pat::Lit(expr) => self.infer_expr(*expr, &Expectation::has_type(expected.clone())),
+            &Pat::Lit(expr) => {
+                // FIXME: using `Option` here is a workaround until we can use if-let chains in stable.
+                let mut pat_ty = None;
+
+                // Like slice patterns, byte string patterns can denote both `&[u8; N]` and `&[u8]`.
+                if let Expr::Literal(Literal::ByteString(_)) = self.body[expr] {
+                    if let Some((inner, ..)) = expected.as_reference() {
+                        let inner = self.resolve_ty_shallow(inner);
+                        if matches!(inner.kind(Interner), TyKind::Slice(_)) {
+                            let elem_ty = TyKind::Scalar(Scalar::Uint(UintTy::U8)).intern(Interner);
+                            let slice_ty = TyKind::Slice(elem_ty).intern(Interner);
+                            let ty = TyKind::Ref(Mutability::Not, static_lifetime(), slice_ty)
+                                .intern(Interner);
+                            self.write_expr_ty(expr, ty.clone());
+                            pat_ty = Some(ty);
+                        }
+                    }
+                }
+
+                pat_ty.unwrap_or_else(|| {
+                    self.infer_expr(expr, &Expectation::has_type(expected.clone()))
+                })
+            }
             Pat::Box { inner } => match self.resolve_boxed_box() {
                 Some(box_adt) => {
                     let (inner_ty, alloc_ty) = match expected.as_adt() {
@@ -343,7 +366,9 @@ fn is_non_ref_pat(body: &hir_def::body::Body, pat: PatId) -> bool {
         // FIXME: ConstBlock/Path/Lit might actually evaluate to ref, but inference is unimplemented.
         Pat::Path(..) => true,
         Pat::ConstBlock(..) => true,
-        Pat::Lit(expr) => !matches!(body[*expr], Expr::Literal(Literal::String(..))),
+        Pat::Lit(expr) => {
+            !matches!(body[*expr], Expr::Literal(Literal::String(..) | Literal::ByteString(..)))
+        }
         Pat::Bind {
             mode: BindingAnnotation::Mutable | BindingAnnotation::Unannotated,
             subpat: Some(subpat),

crates/hir-ty/src/tests/patterns.rs

@@ -315,6 +315,51 @@ fn infer_pattern_match_string_literal() {
     );
 }
 
+#[test]
+fn infer_pattern_match_byte_string_literal() {
+    check_infer_with_mismatches(
+        r#"
+        //- minicore: index
+        struct S;
+        impl<T, const N: usize> core::ops::Index<S> for [T; N] {
+            type Output = [u8];
+            fn index(&self, index: core::ops::RangeFull) -> &Self::Output {
+                loop {}
+            }
+        }
+        fn test(v: [u8; 3]) {
+            if let b"foo" = &v[S] {}
+            if let b"foo" = &v {}
+        }
+        "#,
+        expect![[r#"
+            105..109 'self': &[T; N]
+            111..116 'index': {unknown}
+            157..180 '{     ...     }': &[u8]
+            167..174 'loop {}': !
+            172..174 '{}': ()
+            191..192 'v': [u8; 3]
+            203..261 '{     ...v {} }': ()
+            209..233 'if let...[S] {}': ()
+            212..230 'let b"... &v[S]': bool
+            216..222 'b"foo"': &[u8]
+            216..222 'b"foo"': &[u8]
+            225..230 '&v[S]': &[u8]
+            226..227 'v': [u8; 3]
+            226..230 'v[S]': [u8]
+            228..229 'S': S
+            231..233 '{}': ()
+            238..259 'if let... &v {}': ()
+            241..256 'let b"foo" = &v': bool
+            245..251 'b"foo"': &[u8; 3]
+            245..251 'b"foo"': &[u8; 3]
+            254..256 '&v': &[u8; 3]
+            255..256 'v': [u8; 3]
+            257..259 '{}': ()
+        "#]],
+    );
+}
+
 #[test]
 fn infer_pattern_match_or() {
     check_infer_with_mismatches(

crates/hir/src/diagnostics.rs

@@ -14,6 +14,7 @@ use crate::{MacroKind, Type};
 
 macro_rules! diagnostics {
     ($($diag:ident,)*) => {
+        #[derive(Debug)]
         pub enum AnyDiagnostic {$(
             $diag(Box<$diag>),
         )*}

crates/hir/src/source_analyzer.rs

@@ -368,6 +368,7 @@ impl SourceAnalyzer {
         let local = if field.name_ref().is_some() {
             None
         } else {
+            // Shorthand syntax, resolve to the local
             let path = ModPath::from_segments(PathKind::Plain, once(local_name.clone()));
             match self.resolver.resolve_path_in_value_ns_fully(db.upcast(), &path) {
                 Some(ValueNs::LocalBinding(pat_id)) => {

crates/ide-assists/src/assist_context.rs

@@ -1,28 +1,20 @@
 //! See [`AssistContext`].
 
-use std::mem;
-
 use hir::Semantics;
-use ide_db::{
-    base_db::{AnchoredPathBuf, FileId, FileRange},
-    SnippetCap,
-};
-use ide_db::{
-    label::Label,
-    source_change::{FileSystemEdit, SourceChange},
-    RootDatabase,
-};
+use ide_db::base_db::{FileId, FileRange};
+use ide_db::{label::Label, RootDatabase};
 use syntax::{
     algo::{self, find_node_at_offset, find_node_at_range},
-    AstNode, AstToken, Direction, SourceFile, SyntaxElement, SyntaxKind, SyntaxNode, SyntaxNodePtr,
-    SyntaxToken, TextRange, TextSize, TokenAtOffset,
+    AstNode, AstToken, Direction, SourceFile, SyntaxElement, SyntaxKind, SyntaxToken, TextRange,
+    TextSize, TokenAtOffset,
 };
-use text_edit::{TextEdit, TextEditBuilder};
 
 use crate::{
     assist_config::AssistConfig, Assist, AssistId, AssistKind, AssistResolveStrategy, GroupLabel,
 };
 
+pub(crate) use ide_db::source_change::{SourceChangeBuilder, TreeMutator};
+
 /// `AssistContext` allows to apply an assist or check if it could be applied.
 ///
 /// Assists use a somewhat over-engineered approach, given the current needs.
@@ -163,7 +155,7 @@ impl Assists {
         id: AssistId,
         label: impl Into<String>,
         target: TextRange,
-        f: impl FnOnce(&mut AssistBuilder),
+        f: impl FnOnce(&mut SourceChangeBuilder),
     ) -> Option<()> {
         let mut f = Some(f);
         self.add_impl(None, id, label.into(), target, &mut |it| f.take().unwrap()(it))
@@ -175,7 +167,7 @@ impl Assists {
         id: AssistId,
         label: impl Into<String>,
         target: TextRange,
-        f: impl FnOnce(&mut AssistBuilder),
+        f: impl FnOnce(&mut SourceChangeBuilder),
     ) -> Option<()> {
         let mut f = Some(f);
         self.add_impl(Some(group), id, label.into(), target, &mut |it| f.take().unwrap()(it))
@@ -187,7 +179,7 @@ impl Assists {
         id: AssistId,
         label: String,
         target: TextRange,
-        f: &mut dyn FnMut(&mut AssistBuilder),
+        f: &mut dyn FnMut(&mut SourceChangeBuilder),
     ) -> Option<()> {
         if !self.is_allowed(&id) {
             return None;
@@ -195,7 +187,7 @@ impl Assists {
 
         let mut trigger_signature_help = false;
         let source_change = if self.resolve.should_resolve(&id) {
-            let mut builder = AssistBuilder::new(self.file);
+            let mut builder = SourceChangeBuilder::new(self.file);
             f(&mut builder);
             trigger_signature_help = builder.trigger_signature_help;
             Some(builder.finish())
@@ -216,132 +208,3 @@ impl Assists {
         }
     }
 }
-
-pub(crate) struct AssistBuilder {
-    edit: TextEditBuilder,
-    file_id: FileId,
-    source_change: SourceChange,
-    trigger_signature_help: bool,
-
-    /// Maps the original, immutable `SyntaxNode` to a `clone_for_update` twin.
-    mutated_tree: Option<TreeMutator>,
-}
-
-pub(crate) struct TreeMutator {
-    immutable: SyntaxNode,
-    mutable_clone: SyntaxNode,
-}
-
-impl TreeMutator {
-    pub(crate) fn new(immutable: &SyntaxNode) -> TreeMutator {
-        let immutable = immutable.ancestors().last().unwrap();
-        let mutable_clone = immutable.clone_for_update();
-        TreeMutator { immutable, mutable_clone }
-    }
-
-    pub(crate) fn make_mut<N: AstNode>(&self, node: &N) -> N {
-        N::cast(self.make_syntax_mut(node.syntax())).unwrap()
-    }
-
-    pub(crate) fn make_syntax_mut(&self, node: &SyntaxNode) -> SyntaxNode {
-        let ptr = SyntaxNodePtr::new(node);
-        ptr.to_node(&self.mutable_clone)
-    }
-}
-
-impl AssistBuilder {
-    pub(crate) fn new(file_id: FileId) -> AssistBuilder {
-        AssistBuilder {
-            edit: TextEdit::builder(),
-            file_id,
-            source_change: SourceChange::default(),
-            trigger_signature_help: false,
-            mutated_tree: None,
-        }
-    }
-
-    pub(crate) fn edit_file(&mut self, file_id: FileId) {
-        self.commit();
-        self.file_id = file_id;
-    }
-
-    fn commit(&mut self) {
-        if let Some(tm) = self.mutated_tree.take() {
-            algo::diff(&tm.immutable, &tm.mutable_clone).into_text_edit(&mut self.edit)
-        }
-
-        let edit = mem::take(&mut self.edit).finish();
-        if !edit.is_empty() {
-            self.source_change.insert_source_edit(self.file_id, edit);
-        }
-    }
-
-    pub(crate) fn make_mut<N: AstNode>(&mut self, node: N) -> N {
-        self.mutated_tree.get_or_insert_with(|| TreeMutator::new(node.syntax())).make_mut(&node)
-    }
-    /// Returns a copy of the `node`, suitable for mutation.
-    ///
-    /// Syntax trees in rust-analyzer are typically immutable, and mutating
-    /// operations panic at runtime. However, it is possible to make a copy of
-    /// the tree and mutate the copy freely. Mutation is based on interior
-    /// mutability, and different nodes in the same tree see the same mutations.
-    ///
-    /// The typical pattern for an assist is to find specific nodes in the read
-    /// phase, and then get their mutable couterparts using `make_mut` in the
-    /// mutable state.
-    pub(crate) fn make_syntax_mut(&mut self, node: SyntaxNode) -> SyntaxNode {
-        self.mutated_tree.get_or_insert_with(|| TreeMutator::new(&node)).make_syntax_mut(&node)
-    }
-
-    /// Remove specified `range` of text.
-    pub(crate) fn delete(&mut self, range: TextRange) {
-        self.edit.delete(range)
-    }
-    /// Append specified `text` at the given `offset`
-    pub(crate) fn insert(&mut self, offset: TextSize, text: impl Into<String>) {
-        self.edit.insert(offset, text.into())
-    }
-    /// Append specified `snippet` at the given `offset`
-    pub(crate) fn insert_snippet(
-        &mut self,
-        _cap: SnippetCap,
-        offset: TextSize,
-        snippet: impl Into<String>,
-    ) {
-        self.source_change.is_snippet = true;
-        self.insert(offset, snippet);
-    }
-    /// Replaces specified `range` of text with a given string.
-    pub(crate) fn replace(&mut self, range: TextRange, replace_with: impl Into<String>) {
-        self.edit.replace(range, replace_with.into())
-    }
-    /// Replaces specified `range` of text with a given `snippet`.
-    pub(crate) fn replace_snippet(
-        &mut self,
-        _cap: SnippetCap,
-        range: TextRange,
-        snippet: impl Into<String>,
-    ) {
-        self.source_change.is_snippet = true;
-        self.replace(range, snippet);
-    }
-    pub(crate) fn replace_ast<N: AstNode>(&mut self, old: N, new: N) {
-        algo::diff(old.syntax(), new.syntax()).into_text_edit(&mut self.edit)
-    }
-    pub(crate) fn create_file(&mut self, dst: AnchoredPathBuf, content: impl Into<String>) {
-        let file_system_edit = FileSystemEdit::CreateFile { dst, initial_contents: content.into() };
-        self.source_change.push_file_system_edit(file_system_edit);
-    }
-    pub(crate) fn move_file(&mut self, src: FileId, dst: AnchoredPathBuf) {
-        let file_system_edit = FileSystemEdit::MoveFile { src, dst };
-        self.source_change.push_file_system_edit(file_system_edit);
-    }
-    pub(crate) fn trigger_signature_help(&mut self) {
-        self.trigger_signature_help = true;
-    }
-
-    fn finish(mut self) -> SourceChange {
-        self.commit();
-        mem::take(&mut self.source_change)
-    }
-}

crates/ide-assists/src/handlers/add_missing_impl_members.rs

@@ -944,7 +944,7 @@ foo!();
 struct Foo(usize);
 
 impl FooB for Foo {
-    $0fn foo< 'lt>(& 'lt self){}
+    $0fn foo<'lt>(&'lt self){}
 }
 "#,
         )

crates/ide-assists/src/handlers/convert_tuple_struct_to_named_struct.rs

@@ -5,7 +5,7 @@ use syntax::{
     match_ast, SyntaxNode,
 };
 
-use crate::{assist_context::AssistBuilder, AssistContext, AssistId, AssistKind, Assists};
+use crate::{assist_context::SourceChangeBuilder, AssistContext, AssistId, AssistKind, Assists};
 
 // Assist: convert_tuple_struct_to_named_struct
 //
@@ -80,7 +80,7 @@ pub(crate) fn convert_tuple_struct_to_named_struct(
 
 fn edit_struct_def(
     ctx: &AssistContext<'_>,
-    edit: &mut AssistBuilder,
+    edit: &mut SourceChangeBuilder,
     strukt: &Either<ast::Struct, ast::Variant>,
     tuple_fields: ast::TupleFieldList,
     names: Vec<ast::Name>,
@@ -122,7 +122,7 @@ fn edit_struct_def(
 
 fn edit_struct_references(
     ctx: &AssistContext<'_>,
-    edit: &mut AssistBuilder,
+    edit: &mut SourceChangeBuilder,
     strukt: Either<hir::Struct, hir::Variant>,
     names: &[ast::Name],
 ) {
@@ -132,7 +132,7 @@ fn edit_struct_references(
     };
     let usages = strukt_def.usages(&ctx.sema).include_self_refs().all();
 
-    let edit_node = |edit: &mut AssistBuilder, node: SyntaxNode| -> Option<()> {
+    let edit_node = |edit: &mut SourceChangeBuilder, node: SyntaxNode| -> Option<()> {
         match_ast! {
             match node {
                 ast::TupleStructPat(tuple_struct_pat) => {
@@ -203,7 +203,7 @@ fn edit_struct_references(
 
 fn edit_field_references(
     ctx: &AssistContext<'_>,
-    edit: &mut AssistBuilder,
+    edit: &mut SourceChangeBuilder,
     fields: impl Iterator<Item = ast::TupleField>,
     names: &[ast::Name],
 ) {

crates/ide-assists/src/handlers/destructure_tuple_binding.rs

@@ -8,7 +8,7 @@ use syntax::{
     TextRange,
 };
 
-use crate::assist_context::{AssistBuilder, AssistContext, Assists};
+use crate::assist_context::{AssistContext, Assists, SourceChangeBuilder};
 
 // Assist: destructure_tuple_binding
 //
@@ -151,7 +151,7 @@ struct TupleData {
 }
 fn edit_tuple_assignment(
     ctx: &AssistContext<'_>,
-    builder: &mut AssistBuilder,
+    builder: &mut SourceChangeBuilder,
     data: &TupleData,
     in_sub_pattern: bool,
 ) {
@@ -195,7 +195,7 @@ fn edit_tuple_assignment(
 
 fn edit_tuple_usages(
     data: &TupleData,
-    builder: &mut AssistBuilder,
+    builder: &mut SourceChangeBuilder,
     ctx: &AssistContext<'_>,
     in_sub_pattern: bool,
 ) {
@@ -211,7 +211,7 @@ fn edit_tuple_usages(
 }
 fn edit_tuple_usage(
     ctx: &AssistContext<'_>,
-    builder: &mut AssistBuilder,
+    builder: &mut SourceChangeBuilder,
     usage: &FileReference,
     data: &TupleData,
     in_sub_pattern: bool,
@@ -239,7 +239,7 @@ fn edit_tuple_usage(
 
 fn edit_tuple_field_usage(
     ctx: &AssistContext<'_>,
-    builder: &mut AssistBuilder,
+    builder: &mut SourceChangeBuilder,
     data: &TupleData,
     index: TupleIndex,
 ) {

crates/ide-assists/src/handlers/extract_struct_from_enum_variant.rs

@@ -20,7 +20,7 @@ use syntax::{
     SyntaxNode, T,
 };
 
-use crate::{assist_context::AssistBuilder, AssistContext, AssistId, AssistKind, Assists};
+use crate::{assist_context::SourceChangeBuilder, AssistContext, AssistId, AssistKind, Assists};
 
 // Assist: extract_struct_from_enum_variant
 //
@@ -374,7 +374,7 @@ fn apply_references(
 
 fn process_references(
     ctx: &AssistContext<'_>,
-    builder: &mut AssistBuilder,
+    builder: &mut SourceChangeBuilder,
     visited_modules: &mut FxHashSet<Module>,
     enum_module_def: &ModuleDef,
     variant_hir_name: &Name,

crates/ide-assists/src/handlers/generate_deref.rs

@@ -8,7 +8,7 @@ use syntax::{
 };
 
 use crate::{
-    assist_context::{AssistBuilder, AssistContext, Assists},
+    assist_context::{AssistContext, Assists, SourceChangeBuilder},
     utils::generate_trait_impl_text,
     AssistId, AssistKind,
 };
@@ -120,7 +120,7 @@ fn generate_tuple_deref(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()
 }
 
 fn generate_edit(
-    edit: &mut AssistBuilder,
+    edit: &mut SourceChangeBuilder,
     strukt: ast::Struct,
     field_type_syntax: &SyntaxNode,
     field_name: impl Display,

crates/ide-assists/src/handlers/introduce_named_lifetime.rs

@@ -5,7 +5,7 @@ use syntax::{
     AstNode, TextRange,
 };
 
-use crate::{assist_context::AssistBuilder, AssistContext, AssistId, AssistKind, Assists};
+use crate::{assist_context::SourceChangeBuilder, AssistContext, AssistId, AssistKind, Assists};
 
 static ASSIST_NAME: &str = "introduce_named_lifetime";
 static ASSIST_LABEL: &str = "Introduce named lifetime";
@@ -140,7 +140,7 @@ enum NeedsLifetime {
 }
 
 impl NeedsLifetime {
-    fn make_mut(self, builder: &mut AssistBuilder) -> Self {
+    fn make_mut(self, builder: &mut SourceChangeBuilder) -> Self {
         match self {
             Self::SelfParam(it) => Self::SelfParam(builder.make_mut(it)),
             Self::RefType(it) => Self::RefType(builder.make_mut(it)),

crates/ide-assists/src/handlers/remove_unused_param.rs

@@ -8,7 +8,8 @@ use syntax::{
 use SyntaxKind::WHITESPACE;
 
 use crate::{
-    assist_context::AssistBuilder, utils::next_prev, AssistContext, AssistId, AssistKind, Assists,
+    assist_context::SourceChangeBuilder, utils::next_prev, AssistContext, AssistId, AssistKind,
+    Assists,
 };
 
 // Assist: remove_unused_param
@@ -88,7 +89,7 @@ pub(crate) fn remove_unused_param(acc: &mut Assists, ctx: &AssistContext<'_>) ->
 
 fn process_usages(
     ctx: &AssistContext<'_>,
-    builder: &mut AssistBuilder,
+    builder: &mut SourceChangeBuilder,
     file_id: FileId,
     references: Vec<FileReference>,
     arg_to_remove: usize,

crates/ide-assists/src/handlers/replace_derive_with_manual_impl.rs

@@ -10,7 +10,7 @@ use syntax::{
 };
 
 use crate::{
-    assist_context::{AssistBuilder, AssistContext, Assists},
+    assist_context::{AssistContext, Assists, SourceChangeBuilder},
     utils::{
         add_trait_assoc_items_to_impl, filter_assoc_items, gen_trait_fn_body,
         generate_trait_impl_text, render_snippet, Cursor, DefaultMethods,
@@ -224,7 +224,7 @@ fn impl_def_from_trait(
 }
 
 fn update_attribute(
-    builder: &mut AssistBuilder,
+    builder: &mut SourceChangeBuilder,
     old_derives: &[ast::Path],
     old_tree: &ast::TokenTree,
     old_trait_path: &ast::Path,

crates/ide-assists/src/utils.rs

@@ -20,7 +20,7 @@ use syntax::{
     SyntaxNode, TextRange, TextSize, T,
 };
 
-use crate::assist_context::{AssistBuilder, AssistContext};
+use crate::assist_context::{AssistContext, SourceChangeBuilder};
 
 pub(crate) mod suggest_name;
 mod gen_trait_fn_body;
@@ -484,7 +484,7 @@ fn generate_impl_text_inner(adt: &ast::Adt, trait_text: Option<&str>, code: &str
 }
 
 pub(crate) fn add_method_to_adt(
-    builder: &mut AssistBuilder,
+    builder: &mut SourceChangeBuilder,
     adt: &ast::Adt,
     impl_def: Option<ast::Impl>,
     method: &str,

crates/ide-completion/src/completions.rs

@@ -617,7 +617,6 @@ pub(super) fn complete_name_ref(
 
                     dot::complete_undotted_self(acc, ctx, path_ctx, expr_ctx);
                     item_list::complete_item_list_in_expr(acc, ctx, path_ctx, expr_ctx);
-                    record::complete_record_expr_func_update(acc, ctx, path_ctx, expr_ctx);
                     snippet::complete_expr_snippet(acc, ctx, path_ctx, expr_ctx);
                 }
                 PathKind::Type { location } => {

crates/ide-completion/src/completions/expr.rs

@@ -1,8 +1,10 @@
 //! Completion of names from the current scope in expression position.
 
 use hir::ScopeDef;
+use syntax::ast;
 
 use crate::{
+    completions::record::add_default_update,
     context::{ExprCtx, PathCompletionCtx, Qualified},
     CompletionContext, Completions,
 };
@@ -219,60 +221,78 @@ pub(crate) fn complete_expr_path(
                 _ => (),
             });
 
-            if is_func_update.is_none() {
-                let mut add_keyword =
-                    |kw, snippet| acc.add_keyword_snippet_expr(ctx, incomplete_let, kw, snippet);
+            match is_func_update {
+                Some(record_expr) => {
+                    let ty = ctx.sema.type_of_expr(&ast::Expr::RecordExpr(record_expr.clone()));
 
-                if !in_block_expr {
-                    add_keyword("unsafe", "unsafe {\n    $0\n}");
+                    match ty.as_ref().and_then(|t| t.original.as_adt()) {
+                        Some(hir::Adt::Union(_)) => (),
+                        _ => {
+                            cov_mark::hit!(functional_update);
+                            let missing_fields =
+                                ctx.sema.record_literal_missing_fields(record_expr);
+                            if !missing_fields.is_empty() {
+                                add_default_update(acc, ctx, ty);
+                            }
+                        }
+                    };
                 }
-                add_keyword("match", "match $1 {\n    $0\n}");
-                add_keyword("while", "while $1 {\n    $0\n}");
-                add_keyword("while let", "while let $1 = $2 {\n    $0\n}");
-                add_keyword("loop", "loop {\n    $0\n}");
-                if in_match_guard {
-                    add_keyword("if", "if $0");
-                } else {
-                    add_keyword("if", "if $1 {\n    $0\n}");
-                }
-                add_keyword("if let", "if let $1 = $2 {\n    $0\n}");
-                add_keyword("for", "for $1 in $2 {\n    $0\n}");
-                add_keyword("true", "true");
-                add_keyword("false", "false");
+                None => {
+                    let mut add_keyword = |kw, snippet| {
+                        acc.add_keyword_snippet_expr(ctx, incomplete_let, kw, snippet)
+                    };
 
-                if in_condition || in_block_expr {
-                    add_keyword("let", "let");
-                }
-
-                if after_if_expr {
-                    add_keyword("else", "else {\n    $0\n}");
-                    add_keyword("else if", "else if $1 {\n    $0\n}");
-                }
-
-                if wants_mut_token {
-                    add_keyword("mut", "mut ");
-                }
-
-                if in_loop_body {
-                    if in_block_expr {
-                        add_keyword("continue", "continue;");
-                        add_keyword("break", "break;");
-                    } else {
-                        add_keyword("continue", "continue");
-                        add_keyword("break", "break");
+                    if !in_block_expr {
+                        add_keyword("unsafe", "unsafe {\n    $0\n}");
                     }
-                }
+                    add_keyword("match", "match $1 {\n    $0\n}");
+                    add_keyword("while", "while $1 {\n    $0\n}");
+                    add_keyword("while let", "while let $1 = $2 {\n    $0\n}");
+                    add_keyword("loop", "loop {\n    $0\n}");
+                    if in_match_guard {
+                        add_keyword("if", "if $0");
+                    } else {
+                        add_keyword("if", "if $1 {\n    $0\n}");
+                    }
+                    add_keyword("if let", "if let $1 = $2 {\n    $0\n}");
+                    add_keyword("for", "for $1 in $2 {\n    $0\n}");
+                    add_keyword("true", "true");
+                    add_keyword("false", "false");
 
-                if let Some(ty) = innermost_ret_ty {
-                    add_keyword(
-                        "return",
-                        match (in_block_expr, ty.is_unit()) {
-                            (true, true) => "return ;",
-                            (true, false) => "return;",
-                            (false, true) => "return $0",
-                            (false, false) => "return",
-                        },
-                    );
+                    if in_condition || in_block_expr {
+                        add_keyword("let", "let");
+                    }
+
+                    if after_if_expr {
+                        add_keyword("else", "else {\n    $0\n}");
+                        add_keyword("else if", "else if $1 {\n    $0\n}");
+                    }
+
+                    if wants_mut_token {
+                        add_keyword("mut", "mut ");
+                    }
+
+                    if in_loop_body {
+                        if in_block_expr {
+                            add_keyword("continue", "continue;");
+                            add_keyword("break", "break;");
+                        } else {
+                            add_keyword("continue", "continue");
+                            add_keyword("break", "break");
+                        }
+                    }
+
+                    if let Some(ty) = innermost_ret_ty {
+                        add_keyword(
+                            "return",
+                            match (in_block_expr, ty.is_unit()) {
+                                (true, true) => "return ;",
+                                (true, false) => "return;",
+                                (false, true) => "return $0",
+                                (false, false) => "return",
+                            },
+                        );
+                    }
                 }
             }
         }

crates/ide-completion/src/completions/item_list/trait_impl.rs

@@ -233,7 +233,8 @@ fn add_type_alias_impl(
     type_alias: hir::TypeAlias,
 ) {
     let alias_name = type_alias.name(ctx.db);
-    let (alias_name, escaped_name) = (alias_name.to_smol_str(), alias_name.escaped().to_smol_str());
+    let (alias_name, escaped_name) =
+        (alias_name.unescaped().to_smol_str(), alias_name.to_smol_str());
 
     let label = format!("type {} =", alias_name);
     let replacement = format!("type {} = ", escaped_name);

crates/ide-completion/src/completions/record.rs

@@ -3,7 +3,7 @@ use ide_db::SymbolKind;
 use syntax::ast::{self, Expr};
 
 use crate::{
-    context::{DotAccess, DotAccessKind, ExprCtx, PathCompletionCtx, PatternContext, Qualified},
+    context::{DotAccess, DotAccessKind, PatternContext},
     CompletionContext, CompletionItem, CompletionItemKind, CompletionRelevance,
     CompletionRelevancePostfixMatch, Completions,
 };
@@ -14,7 +14,24 @@ pub(crate) fn complete_record_pattern_fields(
     pattern_ctx: &PatternContext,
 ) {
     if let PatternContext { record_pat: Some(record_pat), .. } = pattern_ctx {
-        complete_fields(acc, ctx, ctx.sema.record_pattern_missing_fields(record_pat));
+        let ty = ctx.sema.type_of_pat(&ast::Pat::RecordPat(record_pat.clone()));
+        let missing_fields = match ty.as_ref().and_then(|t| t.original.as_adt()) {
+            Some(hir::Adt::Union(un)) => {
+                // ctx.sema.record_pat_missing_fields will always return
+                // an empty Vec on a union literal. This is normally
+                // reasonable, but here we'd like to present the full list
+                // of fields if the literal is empty.
+                let were_fields_specified =
+                    record_pat.record_pat_field_list().and_then(|fl| fl.fields().next()).is_some();
+
+                match were_fields_specified {
+                    false => un.fields(ctx.db).into_iter().map(|f| (f, f.ty(ctx.db))).collect(),
+                    true => return,
+                }
+            }
+            _ => ctx.sema.record_pattern_missing_fields(record_pat),
+        };
+        complete_fields(acc, ctx, missing_fields);
     }
 }
 
@@ -42,8 +59,13 @@ pub(crate) fn complete_record_expr_fields(
         }
         _ => {
             let missing_fields = ctx.sema.record_literal_missing_fields(record_expr);
-            add_default_update(acc, ctx, ty, &missing_fields);
+
+            if !missing_fields.is_empty() {
+                cov_mark::hit!(functional_update_field);
+                add_default_update(acc, ctx, ty);
+            }
             if dot_prefix {
+                cov_mark::hit!(functional_update_one_dot);
                 let mut item =
                     CompletionItem::new(CompletionItemKind::Snippet, ctx.source_range(), "..");
                 item.insert_text(".");
@@ -56,41 +78,18 @@ pub(crate) fn complete_record_expr_fields(
     complete_fields(acc, ctx, missing_fields);
 }
 
-// FIXME: This should probably be part of complete_path_expr
-pub(crate) fn complete_record_expr_func_update(
-    acc: &mut Completions,
-    ctx: &CompletionContext<'_>,
-    path_ctx: &PathCompletionCtx,
-    expr_ctx: &ExprCtx,
-) {
-    if !matches!(path_ctx.qualified, Qualified::No) {
-        return;
-    }
-    if let ExprCtx { is_func_update: Some(record_expr), .. } = expr_ctx {
-        let ty = ctx.sema.type_of_expr(&Expr::RecordExpr(record_expr.clone()));
-
-        match ty.as_ref().and_then(|t| t.original.as_adt()) {
-            Some(hir::Adt::Union(_)) => (),
-            _ => {
-                let missing_fields = ctx.sema.record_literal_missing_fields(record_expr);
-                add_default_update(acc, ctx, ty, &missing_fields);
-            }
-        };
-    }
-}
-
-fn add_default_update(
+pub(crate) fn add_default_update(
     acc: &mut Completions,
     ctx: &CompletionContext<'_>,
     ty: Option<hir::TypeInfo>,
-    missing_fields: &[(hir::Field, hir::Type)],
 ) {
     let default_trait = ctx.famous_defs().core_default_Default();
-    let impl_default_trait = default_trait
+    let impls_default_trait = default_trait
         .zip(ty.as_ref())
         .map_or(false, |(default_trait, ty)| ty.original.impls_trait(ctx.db, default_trait, &[]));
-    if impl_default_trait && !missing_fields.is_empty() {
+    if impls_default_trait {
         // FIXME: This should make use of scope_def like completions so we get all the other goodies
+        // that is we should handle this like actually completing the default function
         let completion_text = "..Default::default()";
         let mut item = CompletionItem::new(SymbolKind::Field, ctx.source_range(), completion_text);
         let completion_text =

crates/ide-completion/src/context.rs

@@ -134,6 +134,7 @@ pub(crate) struct ExprCtx {
     pub(crate) in_condition: bool,
     pub(crate) incomplete_let: bool,
     pub(crate) ref_expr_parent: Option<ast::RefExpr>,
+    /// The surrounding RecordExpression we are completing a functional update
     pub(crate) is_func_update: Option<ast::RecordExpr>,
     pub(crate) self_param: Option<hir::SelfParam>,
     pub(crate) innermost_ret_ty: Option<hir::Type>,

crates/ide-completion/src/render.rs

@@ -117,7 +117,7 @@ pub(crate) fn render_field(
 ) -> CompletionItem {
     let is_deprecated = ctx.is_deprecated(field);
     let name = field.name(ctx.db());
-    let (name, escaped_name) = (name.to_smol_str(), name.escaped().to_smol_str());
+    let (name, escaped_name) = (name.unescaped().to_smol_str(), name.to_smol_str());
     let mut item = CompletionItem::new(
         SymbolKind::Field,
         ctx.source_range(),
@@ -283,8 +283,8 @@ fn render_resolution_path(
 
     let name = local_name.to_smol_str();
     let mut item = render_resolution_simple_(ctx, &local_name, import_to_add, resolution);
-    if local_name.escaped().is_escaped() {
-        item.insert_text(local_name.escaped().to_smol_str());
+    if local_name.is_escaped() {
+        item.insert_text(local_name.to_smol_str());
     }
     // Add `<>` for generic types
     let type_path_no_ty_args = matches!(
@@ -306,7 +306,7 @@ fn render_resolution_path(
                 item.lookup_by(name.clone())
                     .label(SmolStr::from_iter([&name, "<…>"]))
                     .trigger_call_info()
-                    .insert_snippet(cap, format!("{}<$0>", local_name.escaped()));
+                    .insert_snippet(cap, format!("{}<$0>", local_name));
             }
         }
     }
@@ -342,7 +342,8 @@ fn render_resolution_simple_(
     let ctx = ctx.import_to_add(import_to_add);
     let kind = res_to_kind(resolution);
 
-    let mut item = CompletionItem::new(kind, ctx.source_range(), local_name.to_smol_str());
+    let mut item =
+        CompletionItem::new(kind, ctx.source_range(), local_name.unescaped().to_smol_str());
     item.set_relevance(ctx.completion_relevance())
         .set_documentation(scope_def_docs(db, resolution))
         .set_deprecated(scope_def_is_deprecated(&ctx, resolution));

crates/ide-completion/src/render/const_.rs

@@ -13,7 +13,7 @@ pub(crate) fn render_const(ctx: RenderContext<'_>, const_: hir::Const) -> Option
 fn render(ctx: RenderContext<'_>, const_: hir::Const) -> Option<CompletionItem> {
     let db = ctx.db();
     let name = const_.name(db)?;
-    let (name, escaped_name) = (name.to_smol_str(), name.escaped().to_smol_str());
+    let (name, escaped_name) = (name.unescaped().to_smol_str(), name.to_smol_str());
     let detail = const_.display(db).to_string();
 
     let mut item = CompletionItem::new(SymbolKind::Const, ctx.source_range(), name.clone());

crates/ide-completion/src/render/function.rs

@@ -52,10 +52,10 @@ fn render(
 
     let (call, escaped_call) = match &func_kind {
         FuncKind::Method(_, Some(receiver)) => (
-            format!("{}.{}", receiver, &name).into(),
-            format!("{}.{}", receiver.escaped(), name.escaped()).into(),
+            format!("{}.{}", receiver.unescaped(), name.unescaped()).into(),
+            format!("{}.{}", receiver, name).into(),
         ),
-        _ => (name.to_smol_str(), name.escaped().to_smol_str()),
+        _ => (name.unescaped().to_smol_str(), name.to_smol_str()),
     };
     let mut item = CompletionItem::new(
         if func.self_param(db).is_some() {
@@ -96,7 +96,7 @@ fn render(
     item.set_documentation(ctx.docs(func))
         .set_deprecated(ctx.is_deprecated(func) || ctx.is_deprecated_assoc_item(func))
         .detail(detail(db, func))
-        .lookup_by(name.to_smol_str());
+        .lookup_by(name.unescaped().to_smol_str());
 
     match ctx.completion.config.snippet_cap {
         Some(cap) => {

crates/ide-completion/src/render/literal.rs

@@ -73,7 +73,7 @@ fn render(
         None => (name.clone().into(), name.into(), false),
     };
     let (qualified_name, escaped_qualified_name) =
-        (qualified_name.to_string(), qualified_name.escaped().to_string());
+        (qualified_name.unescaped().to_string(), qualified_name.to_string());
     let snippet_cap = ctx.snippet_cap();
 
     let mut rendered = match kind {

crates/ide-completion/src/render/macro_.rs

@@ -46,7 +46,7 @@ fn render(
         ctx.source_range()
     };
 
-    let (name, escaped_name) = (name.to_smol_str(), name.escaped().to_smol_str());
+    let (name, escaped_name) = (name.unescaped().to_smol_str(), name.to_smol_str());
     let docs = ctx.docs(macro_);
     let docs_str = docs.as_ref().map(Documentation::as_str).unwrap_or_default();
     let is_fn_like = macro_.is_fn_like(completion.db);

crates/ide-completion/src/render/pattern.rs

@@ -31,7 +31,7 @@ pub(crate) fn render_struct_pat(
     }
 
     let name = local_name.unwrap_or_else(|| strukt.name(ctx.db()));
-    let (name, escaped_name) = (name.to_smol_str(), name.escaped().to_smol_str());
+    let (name, escaped_name) = (name.unescaped().to_smol_str(), name.to_smol_str());
     let kind = strukt.kind(ctx.db());
     let label = format_literal_label(name.as_str(), kind);
     let pat = render_pat(&ctx, pattern_ctx, &escaped_name, kind, &visible_fields, fields_omitted)?;
@@ -53,10 +53,10 @@ pub(crate) fn render_variant_pat(
     let (visible_fields, fields_omitted) = visible_fields(ctx.completion, &fields, variant)?;
 
     let (name, escaped_name) = match path {
-        Some(path) => (path.to_string().into(), path.escaped().to_string().into()),
+        Some(path) => (path.unescaped().to_string().into(), path.to_string().into()),
         None => {
             let name = local_name.unwrap_or_else(|| variant.name(ctx.db()));
-            (name.to_smol_str(), name.escaped().to_smol_str())
+            (name.unescaped().to_smol_str(), name.to_smol_str())
         }
     };
 
@@ -146,7 +146,7 @@ fn render_record_as_pat(
             format!(
                 "{name} {{ {}{} }}",
                 fields.enumerate().format_with(", ", |(idx, field), f| {
-                    f(&format_args!("{}${}", field.name(db).escaped(), idx + 1))
+                    f(&format_args!("{}${}", field.name(db), idx + 1))
                 }),
                 if fields_omitted { ", .." } else { "" },
                 name = name
@@ -155,7 +155,7 @@ fn render_record_as_pat(
         None => {
             format!(
                 "{name} {{ {}{} }}",
-                fields.map(|field| field.name(db).escaped().to_smol_str()).format(", "),
+                fields.map(|field| field.name(db).to_smol_str()).format(", "),
                 if fields_omitted { ", .." } else { "" },
                 name = name
             )

crates/ide-completion/src/render/type_alias.rs

@@ -32,11 +32,11 @@ fn render(
     let name = type_alias.name(db);
     let (name, escaped_name) = if with_eq {
         (
+            SmolStr::from_iter([&name.unescaped().to_smol_str(), " = "]),
             SmolStr::from_iter([&name.to_smol_str(), " = "]),
-            SmolStr::from_iter([&name.escaped().to_smol_str(), " = "]),
         )
     } else {
-        (name.to_smol_str(), name.escaped().to_smol_str())
+        (name.unescaped().to_smol_str(), name.to_smol_str())
     };
     let detail = type_alias.display(db).to_string();
 

crates/ide-completion/src/render/union_literal.rs

@@ -21,8 +21,8 @@ pub(crate) fn render_union_literal(
     let name = local_name.unwrap_or_else(|| un.name(ctx.db()));
 
     let (qualified_name, escaped_qualified_name) = match path {
-        Some(p) => (p.to_string(), p.escaped().to_string()),
-        None => (name.to_string(), name.escaped().to_string()),
+        Some(p) => (p.unescaped().to_string(), p.to_string()),
+        None => (name.unescaped().to_string(), name.to_string()),
     };
 
     let mut item = CompletionItem::new(
@@ -42,15 +42,15 @@ pub(crate) fn render_union_literal(
         format!(
             "{} {{ ${{1|{}|}}: ${{2:()}} }}$0",
             escaped_qualified_name,
-            fields.iter().map(|field| field.name(ctx.db()).escaped().to_smol_str()).format(",")
+            fields.iter().map(|field| field.name(ctx.db()).to_smol_str()).format(",")
         )
     } else {
         format!(
             "{} {{ {} }}",
             escaped_qualified_name,
-            fields.iter().format_with(", ", |field, f| {
-                f(&format_args!("{}: ()", field.name(ctx.db()).escaped()))
-            })
+            fields
+                .iter()
+                .format_with(", ", |field, f| { f(&format_args!("{}: ()", field.name(ctx.db()))) })
         )
     };
 

crates/ide-completion/src/render/variant.rs

@@ -24,9 +24,9 @@ pub(crate) fn render_record_lit(
 ) -> RenderedLiteral {
     let completions = fields.iter().enumerate().format_with(", ", |(idx, field), f| {
         if snippet_cap.is_some() {
-            f(&format_args!("{}: ${{{}:()}}", field.name(db).escaped(), idx + 1))
+            f(&format_args!("{}: ${{{}:()}}", field.name(db), idx + 1))
         } else {
-            f(&format_args!("{}: ()", field.name(db).escaped()))
+            f(&format_args!("{}: ()", field.name(db)))
         }
     });
 

crates/ide-completion/src/tests/record.rs

@@ -103,47 +103,9 @@ fn foo(f: Struct) {
 }
 
 #[test]
-fn functional_update() {
-    // FIXME: This should filter out all completions that do not have the type `Foo`
-    check(
-        r#"
-//- minicore:default
-struct Foo { foo1: u32, foo2: u32 }
-impl Default for Foo {
-    fn default() -> Self { loop {} }
-}
+fn in_functional_update() {
+    cov_mark::check!(functional_update);
 
-fn main() {
-    let thing = 1;
-    let foo = Foo { foo1: 0, foo2: 0 };
-    let foo2 = Foo { thing, $0 }
-}
-"#,
-        expect![[r#"
-            fd ..Default::default()
-            fd foo1                 u32
-            fd foo2                 u32
-        "#]],
-    );
-    check(
-        r#"
-//- minicore:default
-struct Foo { foo1: u32, foo2: u32 }
-impl Default for Foo {
-    fn default() -> Self { loop {} }
-}
-
-fn main() {
-    let thing = 1;
-    let foo = Foo { foo1: 0, foo2: 0 };
-    let foo2 = Foo { thing, .$0 }
-}
-"#,
-        expect![[r#"
-            fd ..Default::default()
-            sn ..
-        "#]],
-    );
     check(
         r#"
 //- minicore:default
@@ -192,6 +154,56 @@ fn main() {
     );
 }
 
+#[test]
+fn functional_update_no_dot() {
+    cov_mark::check!(functional_update_field);
+    // FIXME: This should filter out all completions that do not have the type `Foo`
+    check(
+        r#"
+//- minicore:default
+struct Foo { foo1: u32, foo2: u32 }
+impl Default for Foo {
+    fn default() -> Self { loop {} }
+}
+
+fn main() {
+    let thing = 1;
+    let foo = Foo { foo1: 0, foo2: 0 };
+    let foo2 = Foo { thing, $0 }
+}
+"#,
+        expect![[r#"
+            fd ..Default::default()
+            fd foo1                 u32
+            fd foo2                 u32
+        "#]],
+    );
+}
+
+#[test]
+fn functional_update_one_dot() {
+    cov_mark::check!(functional_update_one_dot);
+    check(
+        r#"
+//- minicore:default
+struct Foo { foo1: u32, foo2: u32 }
+impl Default for Foo {
+    fn default() -> Self { loop {} }
+}
+
+fn main() {
+    let thing = 1;
+    let foo = Foo { foo1: 0, foo2: 0 };
+    let foo2 = Foo { thing, .$0 }
+}
+"#,
+        expect![[r#"
+            fd ..Default::default()
+            sn ..
+        "#]],
+    );
+}
+
 #[test]
 fn empty_union_literal() {
     check(

crates/ide-db/src/search.rs

@@ -4,7 +4,7 @@
 //! get a super-set of matches. Then, we we confirm each match using precise
 //! name resolution.
 
-use std::{convert::TryInto, mem, sync::Arc};
+use std::{mem, sync::Arc};
 
 use base_db::{FileId, FileRange, SourceDatabase, SourceDatabaseExt};
 use hir::{DefWithBody, HasAttrs, HasSource, InFile, ModuleSource, Semantics, Visibility};

crates/ide-db/src/source_change.rs

@@ -3,12 +3,15 @@
 //!
 //! It can be viewed as a dual for `Change`.
 
-use std::{collections::hash_map::Entry, iter};
+use std::{collections::hash_map::Entry, iter, mem};
 
 use base_db::{AnchoredPathBuf, FileId};
 use rustc_hash::FxHashMap;
 use stdx::never;
-use text_edit::TextEdit;
+use syntax::{algo, AstNode, SyntaxNode, SyntaxNodePtr, TextRange, TextSize};
+use text_edit::{TextEdit, TextEditBuilder};
+
+use crate::SnippetCap;
 
 #[derive(Default, Debug, Clone)]
 pub struct SourceChange {
@@ -81,6 +84,135 @@ impl From<FxHashMap<FileId, TextEdit>> for SourceChange {
     }
 }
 
+pub struct SourceChangeBuilder {
+    pub edit: TextEditBuilder,
+    pub file_id: FileId,
+    pub source_change: SourceChange,
+    pub trigger_signature_help: bool,
+
+    /// Maps the original, immutable `SyntaxNode` to a `clone_for_update` twin.
+    pub mutated_tree: Option<TreeMutator>,
+}
+
+pub struct TreeMutator {
+    immutable: SyntaxNode,
+    mutable_clone: SyntaxNode,
+}
+
+impl TreeMutator {
+    pub fn new(immutable: &SyntaxNode) -> TreeMutator {
+        let immutable = immutable.ancestors().last().unwrap();
+        let mutable_clone = immutable.clone_for_update();
+        TreeMutator { immutable, mutable_clone }
+    }
+
+    pub fn make_mut<N: AstNode>(&self, node: &N) -> N {
+        N::cast(self.make_syntax_mut(node.syntax())).unwrap()
+    }
+
+    pub fn make_syntax_mut(&self, node: &SyntaxNode) -> SyntaxNode {
+        let ptr = SyntaxNodePtr::new(node);
+        ptr.to_node(&self.mutable_clone)
+    }
+}
+
+impl SourceChangeBuilder {
+    pub fn new(file_id: FileId) -> SourceChangeBuilder {
+        SourceChangeBuilder {
+            edit: TextEdit::builder(),
+            file_id,
+            source_change: SourceChange::default(),
+            trigger_signature_help: false,
+            mutated_tree: None,
+        }
+    }
+
+    pub fn edit_file(&mut self, file_id: FileId) {
+        self.commit();
+        self.file_id = file_id;
+    }
+
+    fn commit(&mut self) {
+        if let Some(tm) = self.mutated_tree.take() {
+            algo::diff(&tm.immutable, &tm.mutable_clone).into_text_edit(&mut self.edit)
+        }
+
+        let edit = mem::take(&mut self.edit).finish();
+        if !edit.is_empty() {
+            self.source_change.insert_source_edit(self.file_id, edit);
+        }
+    }
+
+    pub fn make_mut<N: AstNode>(&mut self, node: N) -> N {
+        self.mutated_tree.get_or_insert_with(|| TreeMutator::new(node.syntax())).make_mut(&node)
+    }
+    /// Returns a copy of the `node`, suitable for mutation.
+    ///
+    /// Syntax trees in rust-analyzer are typically immutable, and mutating
+    /// operations panic at runtime. However, it is possible to make a copy of
+    /// the tree and mutate the copy freely. Mutation is based on interior
+    /// mutability, and different nodes in the same tree see the same mutations.
+    ///
+    /// The typical pattern for an assist is to find specific nodes in the read
+    /// phase, and then get their mutable couterparts using `make_mut` in the
+    /// mutable state.
+    pub fn make_syntax_mut(&mut self, node: SyntaxNode) -> SyntaxNode {
+        self.mutated_tree.get_or_insert_with(|| TreeMutator::new(&node)).make_syntax_mut(&node)
+    }
+
+    /// Remove specified `range` of text.
+    pub fn delete(&mut self, range: TextRange) {
+        self.edit.delete(range)
+    }
+    /// Append specified `text` at the given `offset`
+    pub fn insert(&mut self, offset: TextSize, text: impl Into<String>) {
+        self.edit.insert(offset, text.into())
+    }
+    /// Append specified `snippet` at the given `offset`
+    pub fn insert_snippet(
+        &mut self,
+        _cap: SnippetCap,
+        offset: TextSize,
+        snippet: impl Into<String>,
+    ) {
+        self.source_change.is_snippet = true;
+        self.insert(offset, snippet);
+    }
+    /// Replaces specified `range` of text with a given string.
+    pub fn replace(&mut self, range: TextRange, replace_with: impl Into<String>) {
+        self.edit.replace(range, replace_with.into())
+    }
+    /// Replaces specified `range` of text with a given `snippet`.
+    pub fn replace_snippet(
+        &mut self,
+        _cap: SnippetCap,
+        range: TextRange,
+        snippet: impl Into<String>,
+    ) {
+        self.source_change.is_snippet = true;
+        self.replace(range, snippet);
+    }
+    pub fn replace_ast<N: AstNode>(&mut self, old: N, new: N) {
+        algo::diff(old.syntax(), new.syntax()).into_text_edit(&mut self.edit)
+    }
+    pub fn create_file(&mut self, dst: AnchoredPathBuf, content: impl Into<String>) {
+        let file_system_edit = FileSystemEdit::CreateFile { dst, initial_contents: content.into() };
+        self.source_change.push_file_system_edit(file_system_edit);
+    }
+    pub fn move_file(&mut self, src: FileId, dst: AnchoredPathBuf) {
+        let file_system_edit = FileSystemEdit::MoveFile { src, dst };
+        self.source_change.push_file_system_edit(file_system_edit);
+    }
+    pub fn trigger_signature_help(&mut self) {
+        self.trigger_signature_help = true;
+    }
+
+    pub fn finish(mut self) -> SourceChange {
+        self.commit();
+        mem::take(&mut self.source_change)
+    }
+}
+
 #[derive(Debug, Clone)]
 pub enum FileSystemEdit {
     CreateFile { dst: AnchoredPathBuf, initial_contents: String },

crates/ide-diagnostics/Cargo.toml

@@ -15,6 +15,7 @@ itertools = "0.10.3"
 
 
 either = "1.7.0"
+serde_json = "1.0.82"
 
 profile = { path = "../profile", version = "0.0.0" }
 stdx = { path = "../stdx", version = "0.0.0" }

crates/ide-diagnostics/src/handlers/inactive_code.rs

@@ -43,7 +43,7 @@ mod tests {
     use crate::{tests::check_diagnostics_with_config, DiagnosticsConfig};
 
     pub(crate) fn check(ra_fixture: &str) {
-        let config = DiagnosticsConfig::default();
+        let config = DiagnosticsConfig::test_sample();
         check_diagnostics_with_config(config, ra_fixture)
     }
 

crates/ide-diagnostics/src/handlers/json_is_not_rust.rs

@@ -0,0 +1,310 @@
+//! This diagnostic provides an assist for creating a struct definition from a JSON
+//! example.
+
+use hir::{PathResolution, Semantics};
+use ide_db::{
+    base_db::FileId,
+    helpers::mod_path_to_ast,
+    imports::insert_use::{insert_use, ImportScope},
+    source_change::SourceChangeBuilder,
+    RootDatabase,
+};
+use itertools::Itertools;
+use stdx::{format_to, never};
+use syntax::{
+    ast::{self, make},
+    SyntaxKind, SyntaxNode,
+};
+use text_edit::TextEdit;
+
+use crate::{fix, Diagnostic, DiagnosticsConfig, Severity};
+
+#[derive(Default)]
+struct State {
+    result: String,
+    struct_counts: usize,
+    has_serialize: bool,
+    has_deserialize: bool,
+}
+
+impl State {
+    fn generate_new_name(&mut self) -> ast::Name {
+        self.struct_counts += 1;
+        make::name(&format!("Struct{}", self.struct_counts))
+    }
+
+    fn serde_derive(&self) -> String {
+        let mut v = vec![];
+        if self.has_serialize {
+            v.push("Serialize");
+        }
+        if self.has_deserialize {
+            v.push("Deserialize");
+        }
+        match v.as_slice() {
+            [] => "".to_string(),
+            [x] => format!("#[derive({x})]\n"),
+            [x, y] => format!("#[derive({x}, {y})]\n"),
+            _ => {
+                never!();
+                "".to_string()
+            }
+        }
+    }
+
+    fn build_struct(&mut self, value: &serde_json::Map<String, serde_json::Value>) -> ast::Type {
+        let name = self.generate_new_name();
+        let ty = make::ty(&name.to_string());
+        let strukt = make::struct_(
+            None,
+            name,
+            None,
+            make::record_field_list(value.iter().sorted_unstable_by_key(|x| x.0).map(
+                |(name, value)| make::record_field(None, make::name(name), self.type_of(value)),
+            ))
+            .into(),
+        );
+        format_to!(self.result, "{}{}\n", self.serde_derive(), strukt);
+        ty
+    }
+
+    fn type_of(&mut self, value: &serde_json::Value) -> ast::Type {
+        match value {
+            serde_json::Value::Null => make::ty_unit(),
+            serde_json::Value::Bool(_) => make::ty("bool"),
+            serde_json::Value::Number(it) => make::ty(if it.is_i64() { "i64" } else { "f64" }),
+            serde_json::Value::String(_) => make::ty("String"),
+            serde_json::Value::Array(it) => {
+                let ty = match it.iter().next() {
+                    Some(x) => self.type_of(x),
+                    None => make::ty_placeholder(),
+                };
+                make::ty(&format!("Vec<{ty}>"))
+            }
+            serde_json::Value::Object(x) => self.build_struct(x),
+        }
+    }
+}
+
+pub(crate) fn json_in_items(
+    sema: &Semantics<'_, RootDatabase>,
+    acc: &mut Vec<Diagnostic>,
+    file_id: FileId,
+    node: &SyntaxNode,
+    config: &DiagnosticsConfig,
+) {
+    (|| {
+        if node.kind() == SyntaxKind::ERROR
+            && node.first_token().map(|x| x.kind()) == Some(SyntaxKind::L_CURLY)
+            && node.last_token().map(|x| x.kind()) == Some(SyntaxKind::R_CURLY)
+        {
+            let node_string = node.to_string();
+            if let Ok(it) = serde_json::from_str(&node_string) {
+                if let serde_json::Value::Object(it) = it {
+                    let import_scope = ImportScope::find_insert_use_container(node, sema)?;
+                    let range = node.text_range();
+                    let mut edit = TextEdit::builder();
+                    edit.delete(range);
+                    let mut state = State::default();
+                    let semantics_scope = sema.scope(node)?;
+                    let scope_resolve =
+                        |it| semantics_scope.speculative_resolve(&make::path_from_text(it));
+                    let scope_has = |it| scope_resolve(it).is_some();
+                    let deserialize_resolved = scope_resolve("::serde::Deserialize");
+                    let serialize_resolved = scope_resolve("::serde::Serialize");
+                    state.has_deserialize = deserialize_resolved.is_some();
+                    state.has_serialize = serialize_resolved.is_some();
+                    state.build_struct(&it);
+                    edit.insert(range.start(), state.result);
+                    acc.push(
+                        Diagnostic::new(
+                            "json-is-not-rust",
+                            "JSON syntax is not valid as a Rust item",
+                            range,
+                        )
+                        .severity(Severity::WeakWarning)
+                        .with_fixes(Some(vec![{
+                            let mut scb = SourceChangeBuilder::new(file_id);
+                            let scope = match import_scope.clone() {
+                                ImportScope::File(it) => ImportScope::File(scb.make_mut(it)),
+                                ImportScope::Module(it) => ImportScope::Module(scb.make_mut(it)),
+                                ImportScope::Block(it) => ImportScope::Block(scb.make_mut(it)),
+                            };
+                            let current_module = semantics_scope.module();
+                            if !scope_has("Serialize") {
+                                if let Some(PathResolution::Def(it)) = serialize_resolved {
+                                    if let Some(it) = current_module.find_use_path_prefixed(
+                                        sema.db,
+                                        it,
+                                        config.insert_use.prefix_kind,
+                                    ) {
+                                        insert_use(
+                                            &scope,
+                                            mod_path_to_ast(&it),
+                                            &config.insert_use,
+                                        );
+                                    }
+                                }
+                            }
+                            if !scope_has("Deserialize") {
+                                if let Some(PathResolution::Def(it)) = deserialize_resolved {
+                                    if let Some(it) = current_module.find_use_path_prefixed(
+                                        sema.db,
+                                        it,
+                                        config.insert_use.prefix_kind,
+                                    ) {
+                                        insert_use(
+                                            &scope,
+                                            mod_path_to_ast(&it),
+                                            &config.insert_use,
+                                        );
+                                    }
+                                }
+                            }
+                            let mut sc = scb.finish();
+                            sc.insert_source_edit(file_id, edit.finish());
+                            fix("convert_json_to_struct", "Convert JSON to struct", sc, range)
+                        }])),
+                    );
+                }
+            }
+        }
+        Some(())
+    })();
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{
+        tests::{check_diagnostics_with_config, check_fix, check_no_fix},
+        DiagnosticsConfig,
+    };
+
+    #[test]
+    fn diagnostic_for_simple_case() {
+        let mut config = DiagnosticsConfig::test_sample();
+        config.disabled.insert("syntax-error".to_string());
+        check_diagnostics_with_config(
+            config,
+            r#"
+            { "foo": "bar" }
+         // ^^^^^^^^^^^^^^^^ 💡 weak: JSON syntax is not valid as a Rust item
+"#,
+        );
+    }
+
+    #[test]
+    fn types_of_primitives() {
+        check_fix(
+            r#"
+            //- /lib.rs crate:lib deps:serde
+            use serde::Serialize;
+
+            fn some_garbage() {
+
+            }
+
+            {$0
+                "foo": "bar",
+                "bar": 2.3,
+                "baz": null,
+                "bay": 57,
+                "box": true
+            }
+            //- /serde.rs crate:serde
+
+            pub trait Serialize {
+                fn serialize() -> u8;
+            }
+            "#,
+            r#"
+            use serde::Serialize;
+
+            fn some_garbage() {
+
+            }
+
+            #[derive(Serialize)]
+            struct Struct1{ bar: f64, bay: i64, baz: (), r#box: bool, foo: String }
+
+            "#,
+        );
+    }
+
+    #[test]
+    fn nested_structs() {
+        check_fix(
+            r#"
+            {$0
+                "foo": "bar",
+                "bar": {
+                    "kind": "Object",
+                    "value": {}
+                }
+            }
+            "#,
+            r#"
+            struct Struct3{  }
+            struct Struct2{ kind: String, value: Struct3 }
+            struct Struct1{ bar: Struct2, foo: String }
+
+            "#,
+        );
+    }
+
+    #[test]
+    fn arrays() {
+        check_fix(
+            r#"
+            //- /lib.rs crate:lib deps:serde
+            {
+                "of_string": ["foo", "2", "x"], $0
+                "of_object": [{
+                    "x": 10,
+                    "y": 20
+                }, {
+                    "x": 10,
+                    "y": 20
+                }],
+                "nested": [[[2]]],
+                "empty": []
+            }
+            //- /serde.rs crate:serde
+
+            pub trait Serialize {
+                fn serialize() -> u8;
+            }
+            pub trait Deserialize {
+                fn deserialize() -> u8;
+            }
+            "#,
+            r#"
+            use serde::Serialize;
+            use serde::Deserialize;
+
+            #[derive(Serialize, Deserialize)]
+            struct Struct2{ x: i64, y: i64 }
+            #[derive(Serialize, Deserialize)]
+            struct Struct1{ empty: Vec<_>, nested: Vec<Vec<Vec<i64>>>, of_object: Vec<Struct2>, of_string: Vec<String> }
+
+            "#,
+        );
+    }
+
+    #[test]
+    fn no_emit_outside_of_item_position() {
+        check_no_fix(
+            r#"
+            fn foo() {
+                let json = {$0
+                    "foo": "bar",
+                    "bar": {
+                        "kind": "Object",
+                        "value": {}
+                    }
+                };
+            }
+            "#,
+        );
+    }
+}

crates/ide-diagnostics/src/handlers/macro_error.rs

@@ -79,7 +79,7 @@ pub macro panic {
 
     #[test]
     fn include_macro_should_allow_empty_content() {
-        let mut config = DiagnosticsConfig::default();
+        let mut config = DiagnosticsConfig::test_sample();
 
         // FIXME: This is a false-positive, the file is actually linked in via
         // `include!` macro

crates/ide-diagnostics/src/handlers/no_such_field.rs

@@ -68,7 +68,7 @@ fn missing_record_expr_field_fixes(
     }
     let new_field = make::record_field(
         None,
-        make::name(&record_expr_field.field_name()?.text()),
+        make::name(&record_expr_field.field_name()?.ident_token()?.text()),
         make::ty(&new_field_type.display_source_code(sema.db, module.into()).ok()?),
     );
 
@@ -109,7 +109,7 @@ fn missing_record_expr_field_fixes(
 
 #[cfg(test)]
 mod tests {
-    use crate::tests::{check_diagnostics, check_fix};
+    use crate::tests::{check_diagnostics, check_fix, check_no_fix};
 
     #[test]
     fn no_such_field_diagnostics() {
@@ -277,6 +277,20 @@ struct Foo {
     bar: i32,
     pub(crate) baz: bool
 }
+"#,
+        )
+    }
+
+    #[test]
+    fn test_tuple_field_on_record_struct() {
+        check_no_fix(
+            r#"
+struct Struct {}
+fn main() {
+    Struct {
+        0$0: 0
+    }
+}
 "#,
         )
     }

crates/ide-diagnostics/src/lib.rs

@@ -50,6 +50,7 @@ mod handlers {
     pub(crate) mod field_shorthand;
     pub(crate) mod useless_braces;
     pub(crate) mod unlinked_file;
+    pub(crate) mod json_is_not_rust;
 }
 
 #[cfg(test)]
@@ -59,6 +60,7 @@ use hir::{diagnostics::AnyDiagnostic, InFile, Semantics};
 use ide_db::{
     assists::{Assist, AssistId, AssistKind, AssistResolveStrategy},
     base_db::{FileId, FileRange, SourceDatabase},
+    imports::insert_use::InsertUseConfig,
     label::Label,
     source_change::SourceChange,
     FxHashSet, RootDatabase,
@@ -139,13 +141,37 @@ impl Default for ExprFillDefaultMode {
     }
 }
 
-#[derive(Default, Debug, Clone)]
+#[derive(Debug, Clone)]
 pub struct DiagnosticsConfig {
     pub proc_macros_enabled: bool,
     pub proc_attr_macros_enabled: bool,
     pub disable_experimental: bool,
     pub disabled: FxHashSet<String>,
     pub expr_fill_default: ExprFillDefaultMode,
+    // FIXME: We may want to include a whole `AssistConfig` here
+    pub insert_use: InsertUseConfig,
+}
+
+impl DiagnosticsConfig {
+    pub fn test_sample() -> Self {
+        use hir::PrefixKind;
+        use ide_db::imports::insert_use::ImportGranularity;
+
+        Self {
+            proc_macros_enabled: Default::default(),
+            proc_attr_macros_enabled: Default::default(),
+            disable_experimental: Default::default(),
+            disabled: Default::default(),
+            expr_fill_default: Default::default(),
+            insert_use: InsertUseConfig {
+                granularity: ImportGranularity::Preserve,
+                enforce_granularity: false,
+                prefix_kind: PrefixKind::Plain,
+                group: false,
+                skip_glob_imports: false,
+            },
+        }
+    }
 }
 
 struct DiagnosticsContext<'a> {
@@ -172,9 +198,12 @@ pub fn diagnostics(
         }),
     );
 
-    for node in parse.tree().syntax().descendants() {
+    let parse = sema.parse(file_id);
+
+    for node in parse.syntax().descendants() {
         handlers::useless_braces::useless_braces(&mut res, file_id, &node);
         handlers::field_shorthand::field_shorthand(&mut res, file_id, &node);
+        handlers::json_is_not_rust::json_in_items(&sema, &mut res, file_id, &node, &config);
     }
 
     let module = sema.to_module_def(file_id);

crates/ide-diagnostics/src/tests.rs

@@ -37,7 +37,7 @@ fn check_nth_fix(nth: usize, ra_fixture_before: &str, ra_fixture_after: &str) {
     let after = trim_indent(ra_fixture_after);
 
     let (db, file_position) = RootDatabase::with_position(ra_fixture_before);
-    let mut conf = DiagnosticsConfig::default();
+    let mut conf = DiagnosticsConfig::test_sample();
     conf.expr_fill_default = ExprFillDefaultMode::Default;
     let diagnostic =
         super::diagnostics(&db, &conf, &AssistResolveStrategy::All, file_position.file_id)
@@ -69,7 +69,7 @@ pub(crate) fn check_no_fix(ra_fixture: &str) {
     let (db, file_position) = RootDatabase::with_position(ra_fixture);
     let diagnostic = super::diagnostics(
         &db,
-        &DiagnosticsConfig::default(),
+        &DiagnosticsConfig::test_sample(),
         &AssistResolveStrategy::All,
         file_position.file_id,
     )
@@ -82,7 +82,7 @@ pub(crate) fn check_expect(ra_fixture: &str, expect: Expect) {
     let (db, file_id) = RootDatabase::with_single_file(ra_fixture);
     let diagnostics = super::diagnostics(
         &db,
-        &DiagnosticsConfig::default(),
+        &DiagnosticsConfig::test_sample(),
         &AssistResolveStrategy::All,
         file_id,
     );
@@ -91,7 +91,7 @@ pub(crate) fn check_expect(ra_fixture: &str, expect: Expect) {
 
 #[track_caller]
 pub(crate) fn check_diagnostics(ra_fixture: &str) {
-    let mut config = DiagnosticsConfig::default();
+    let mut config = DiagnosticsConfig::test_sample();
     config.disabled.insert("inactive-code".to_string());
     check_diagnostics_with_config(config, ra_fixture)
 }
@@ -127,7 +127,7 @@ pub(crate) fn check_diagnostics_with_config(config: DiagnosticsConfig, ra_fixtur
 
 #[test]
 fn test_disabled_diagnostics() {
-    let mut config = DiagnosticsConfig::default();
+    let mut config = DiagnosticsConfig::test_sample();
     config.disabled.insert("unresolved-module".into());
 
     let (db, file_id) = RootDatabase::with_single_file(r#"mod foo;"#);
@@ -137,7 +137,7 @@ fn test_disabled_diagnostics() {
 
     let diagnostics = super::diagnostics(
         &db,
-        &DiagnosticsConfig::default(),
+        &DiagnosticsConfig::test_sample(),
         &AssistResolveStrategy::All,
         file_id,
     );

crates/ide/src/goto_definition.rs

@@ -1,4 +1,4 @@
-use std::{convert::TryInto, mem::discriminant};
+use std::mem::discriminant;
 
 use crate::{doc_links::token_as_doc_comment, FilePosition, NavigationTarget, RangeInfo, TryToNav};
 use hir::{AsAssocItem, AssocItem, Semantics};

crates/ide/src/runnables.rs

@@ -2225,4 +2225,190 @@ macro_rules! foo {
             "#]],
         );
     }
+
+    #[test]
+    fn test_paths_with_raw_ident() {
+        check(
+            r#"
+//- /lib.rs
+$0
+mod r#mod {
+    #[test]
+    fn r#fn() {}
+
+    /// ```
+    /// ```
+    fn r#for() {}
+
+    /// ```
+    /// ```
+    struct r#struct<r#type>(r#type);
+
+    /// ```
+    /// ```
+    impl<r#type> r#struct<r#type> {
+        /// ```
+        /// ```
+        fn r#fn() {}
+    }
+
+    enum r#enum {}
+    impl r#struct<r#enum> {
+        /// ```
+        /// ```
+        fn r#fn() {}
+    }
+
+    trait r#trait {}
+
+    /// ```
+    /// ```
+    impl<T> r#trait for r#struct<T> {}
+}
+"#,
+            &[TestMod, Test, DocTest, DocTest, DocTest, DocTest, DocTest, DocTest],
+            expect![[r#"
+                [
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 1..461,
+                            focus_range: 5..10,
+                            name: "r#mod",
+                            kind: Module,
+                            description: "mod r#mod",
+                        },
+                        kind: TestMod {
+                            path: "r#mod",
+                        },
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 17..41,
+                            focus_range: 32..36,
+                            name: "r#fn",
+                            kind: Function,
+                        },
+                        kind: Test {
+                            test_id: Path(
+                                "r#mod::r#fn",
+                            ),
+                            attr: TestAttr {
+                                ignore: false,
+                            },
+                        },
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 47..84,
+                            name: "r#for",
+                        },
+                        kind: DocTest {
+                            test_id: Path(
+                                "r#mod::r#for",
+                            ),
+                        },
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 90..146,
+                            name: "r#struct",
+                        },
+                        kind: DocTest {
+                            test_id: Path(
+                                "r#mod::r#struct",
+                            ),
+                        },
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 152..266,
+                            focus_range: 189..205,
+                            name: "impl",
+                            kind: Impl,
+                        },
+                        kind: DocTest {
+                            test_id: Path(
+                                "r#struct<r#type>",
+                            ),
+                        },
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 216..260,
+                            name: "r#fn",
+                        },
+                        kind: DocTest {
+                            test_id: Path(
+                                "r#mod::r#struct<r#type>::r#fn",
+                            ),
+                        },
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 323..367,
+                            name: "r#fn",
+                        },
+                        kind: DocTest {
+                            test_id: Path(
+                                "r#mod::r#struct<r#enum>::r#fn",
+                            ),
+                        },
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 401..459,
+                            focus_range: 445..456,
+                            name: "impl",
+                            kind: Impl,
+                        },
+                        kind: DocTest {
+                            test_id: Path(
+                                "r#struct<T>",
+                            ),
+                        },
+                        cfg: None,
+                    },
+                ]
+            "#]],
+        )
+    }
 }

crates/ide/src/status.rs

@@ -1,4 +1,4 @@
-use std::{fmt, iter::FromIterator, sync::Arc};
+use std::{fmt, sync::Arc};
 
 use hir::{ExpandResult, MacroFile};
 use ide_db::base_db::{

crates/mbe/src/syntax_bridge.rs

@@ -228,16 +228,7 @@ fn convert_tokens<C: TokenConvertor>(conv: &mut C) -> tt::Subtree {
             }
 
             let spacing = match conv.peek().map(|next| next.kind(conv)) {
-                Some(kind)
-                    if !kind.is_trivia()
-                        && kind.is_punct()
-                        && kind != T!['[']
-                        && kind != T!['{']
-                        && kind != T!['(']
-                        && kind != UNDERSCORE =>
-                {
-                    tt::Spacing::Joint
-                }
+                Some(kind) if !kind.is_trivia() => tt::Spacing::Joint,
                 _ => tt::Spacing::Alone,
             };
             let char = match token.to_char(conv) {

crates/parser/src/grammar/expressions.rs

@@ -564,8 +564,10 @@ fn path_expr(p: &mut Parser<'_>, r: Restrictions) -> (CompletedMarker, BlockLike
 // test record_lit
 // fn foo() {
 //     S {};
+//     S { x };
 //     S { x, y: 32, };
 //     S { x, y: 32, ..Default::default() };
+//     S { x: ::default() };
 //     TupleStruct { 0: 1 };
 // }
 pub(crate) fn record_expr_field_list(p: &mut Parser<'_>) {
@@ -582,16 +584,26 @@ pub(crate) fn record_expr_field_list(p: &mut Parser<'_>) {
 
         match p.current() {
             IDENT | INT_NUMBER => {
-                // test_err record_literal_before_ellipsis_recovery
+                // test_err record_literal_missing_ellipsis_recovery
                 // fn main() {
-                //     S { field ..S::default() }
+                //     S { S::default() }
                 // }
-                if p.nth_at(1, T![:]) || p.nth_at(1, T![..]) {
-                    name_ref_or_index(p);
-                    p.expect(T![:]);
+                if p.nth_at(1, T![::]) {
+                    m.abandon(p);
+                    p.expect(T![..]);
+                    expr(p);
+                } else {
+                    // test_err record_literal_before_ellipsis_recovery
+                    // fn main() {
+                    //     S { field ..S::default() }
+                    // }
+                    if p.nth_at(1, T![:]) || p.nth_at(1, T![..]) {
+                        name_ref_or_index(p);
+                        p.expect(T![:]);
+                    }
+                    expr(p);
+                    m.complete(p, RECORD_EXPR_FIELD);
                 }
-                expr(p);
-                m.complete(p, RECORD_EXPR_FIELD);
             }
             T![.] if p.at(T![..]) => {
                 m.abandon(p);

crates/parser/src/grammar/patterns.rs

@@ -75,6 +75,16 @@ fn pattern_single_r(p: &mut Parser<'_>, recovery_set: TokenSet) {
         //         Some(1..) => ()
         //     }
         //
+        //     match () {
+        //         S { a: 0 } => (),
+        //         S { a: 1.. } => (),
+        //     }
+        //
+        //     match () {
+        //         [0] => (),
+        //         [1..] => (),
+        //     }
+        //
         //     match (10 as u8, 5 as u8) {
         //         (0, _) => (),
         //         (1.., _) => ()
@@ -88,11 +98,27 @@ fn pattern_single_r(p: &mut Parser<'_>, recovery_set: TokenSet) {
                 let m = lhs.precede(p);
                 p.bump(range_op);
 
-                // `0 .. =>` or `let 0 .. =` or `Some(0 .. )`
-                //       ^                ^                ^
-                if p.at(T![=]) | p.at(T![')']) | p.at(T![,]) {
+                // testing if we're at one of the following positions:
+                // `0 .. =>`
+                //       ^
+                // `let 0 .. =`
+                //           ^
+                // `let 0..: _ =`
+                //         ^
+                // (1.., _)
+                //     ^
+                // `Some(0 .. )`
+                //            ^
+                // `S { t: 0.. }`
+                //             ^
+                // `[0..]`
+                //      ^
+                if matches!(p.current(), T![=] | T![,] | T![:] | T![')'] | T!['}'] | T![']']) {
                     // test half_open_range_pat
-                    // fn f() { let 0 .. = 1u32; }
+                    // fn f() {
+                    //     let 0 .. = 1u32;
+                    //     let 0..: _ = 1u32;
+                    // }
                 } else {
                     atom_pat(p, recovery_set);
                 }

crates/parser/test_data/parser/inline/err/0014_record_literal_missing_ellipsis_recovery.rast

@@ -0,0 +1,43 @@
+SOURCE_FILE
+  FN
+    FN_KW "fn"
+    WHITESPACE " "
+    NAME
+      IDENT "main"
+    PARAM_LIST
+      L_PAREN "("
+      R_PAREN ")"
+    WHITESPACE " "
+    BLOCK_EXPR
+      STMT_LIST
+        L_CURLY "{"
+        WHITESPACE "\n    "
+        RECORD_EXPR
+          PATH
+            PATH_SEGMENT
+              NAME_REF
+                IDENT "S"
+          WHITESPACE " "
+          RECORD_EXPR_FIELD_LIST
+            L_CURLY "{"
+            WHITESPACE " "
+            CALL_EXPR
+              PATH_EXPR
+                PATH
+                  PATH
+                    PATH_SEGMENT
+                      NAME_REF
+                        IDENT "S"
+                  COLON2 "::"
+                  PATH_SEGMENT
+                    NAME_REF
+                      IDENT "default"
+              ARG_LIST
+                L_PAREN "("
+                R_PAREN ")"
+            WHITESPACE " "
+            R_CURLY "}"
+        WHITESPACE "\n"
+        R_CURLY "}"
+  WHITESPACE "\n"
+error 19: expected DOT2

crates/parser/test_data/parser/inline/err/0014_record_literal_missing_ellipsis_recovery.rs

@@ -0,0 +1,3 @@
+fn main() {
+    S { S::default() }
+}

crates/parser/test_data/parser/inline/ok/0058_range_pat.rast

@@ -172,6 +172,122 @@ SOURCE_FILE
               WHITESPACE "\n    "
               R_CURLY "}"
         WHITESPACE "\n\n    "
+        EXPR_STMT
+          MATCH_EXPR
+            MATCH_KW "match"
+            WHITESPACE " "
+            TUPLE_EXPR
+              L_PAREN "("
+              R_PAREN ")"
+            WHITESPACE " "
+            MATCH_ARM_LIST
+              L_CURLY "{"
+              WHITESPACE "\n        "
+              MATCH_ARM
+                RECORD_PAT
+                  PATH
+                    PATH_SEGMENT
+                      NAME_REF
+                        IDENT "S"
+                  WHITESPACE " "
+                  RECORD_PAT_FIELD_LIST
+                    L_CURLY "{"
+                    WHITESPACE " "
+                    RECORD_PAT_FIELD
+                      NAME_REF
+                        IDENT "a"
+                      COLON ":"
+                      WHITESPACE " "
+                      LITERAL_PAT
+                        LITERAL
+                          INT_NUMBER "0"
+                    WHITESPACE " "
+                    R_CURLY "}"
+                WHITESPACE " "
+                FAT_ARROW "=>"
+                WHITESPACE " "
+                TUPLE_EXPR
+                  L_PAREN "("
+                  R_PAREN ")"
+                COMMA ","
+              WHITESPACE "\n        "
+              MATCH_ARM
+                RECORD_PAT
+                  PATH
+                    PATH_SEGMENT
+                      NAME_REF
+                        IDENT "S"
+                  WHITESPACE " "
+                  RECORD_PAT_FIELD_LIST
+                    L_CURLY "{"
+                    WHITESPACE " "
+                    RECORD_PAT_FIELD
+                      NAME_REF
+                        IDENT "a"
+                      COLON ":"
+                      WHITESPACE " "
+                      RANGE_PAT
+                        LITERAL_PAT
+                          LITERAL
+                            INT_NUMBER "1"
+                        DOT2 ".."
+                    WHITESPACE " "
+                    R_CURLY "}"
+                WHITESPACE " "
+                FAT_ARROW "=>"
+                WHITESPACE " "
+                TUPLE_EXPR
+                  L_PAREN "("
+                  R_PAREN ")"
+                COMMA ","
+              WHITESPACE "\n    "
+              R_CURLY "}"
+        WHITESPACE "\n\n    "
+        EXPR_STMT
+          MATCH_EXPR
+            MATCH_KW "match"
+            WHITESPACE " "
+            TUPLE_EXPR
+              L_PAREN "("
+              R_PAREN ")"
+            WHITESPACE " "
+            MATCH_ARM_LIST
+              L_CURLY "{"
+              WHITESPACE "\n        "
+              MATCH_ARM
+                SLICE_PAT
+                  L_BRACK "["
+                  LITERAL_PAT
+                    LITERAL
+                      INT_NUMBER "0"
+                  R_BRACK "]"
+                WHITESPACE " "
+                FAT_ARROW "=>"
+                WHITESPACE " "
+                TUPLE_EXPR
+                  L_PAREN "("
+                  R_PAREN ")"
+                COMMA ","
+              WHITESPACE "\n        "
+              MATCH_ARM
+                SLICE_PAT
+                  L_BRACK "["
+                  RANGE_PAT
+                    LITERAL_PAT
+                      LITERAL
+                        INT_NUMBER "1"
+                    DOT2 ".."
+                  R_BRACK "]"
+                WHITESPACE " "
+                FAT_ARROW "=>"
+                WHITESPACE " "
+                TUPLE_EXPR
+                  L_PAREN "("
+                  R_PAREN ")"
+                COMMA ","
+              WHITESPACE "\n    "
+              R_CURLY "}"
+        WHITESPACE "\n\n    "
         MATCH_EXPR
           MATCH_KW "match"
           WHITESPACE " "

crates/parser/test_data/parser/inline/ok/0058_range_pat.rs

@@ -11,6 +11,16 @@ fn main() {
         Some(1..) => ()
     }
 
+    match () {
+        S { a: 0 } => (),
+        S { a: 1.. } => (),
+    }
+
+    match () {
+        [0] => (),
+        [1..] => (),
+    }
+
     match (10 as u8, 5 as u8) {
         (0, _) => (),
         (1.., _) => ()

crates/parser/test_data/parser/inline/ok/0061_record_lit.rast

@@ -24,6 +24,26 @@ SOURCE_FILE
               R_CURLY "}"
           SEMICOLON ";"
         WHITESPACE "\n    "
+        EXPR_STMT
+          RECORD_EXPR
+            PATH
+              PATH_SEGMENT
+                NAME_REF
+                  IDENT "S"
+            WHITESPACE " "
+            RECORD_EXPR_FIELD_LIST
+              L_CURLY "{"
+              WHITESPACE " "
+              RECORD_EXPR_FIELD
+                PATH_EXPR
+                  PATH
+                    PATH_SEGMENT
+                      NAME_REF
+                        IDENT "x"
+              WHITESPACE " "
+              R_CURLY "}"
+          SEMICOLON ";"
+        WHITESPACE "\n    "
         EXPR_STMT
           RECORD_EXPR
             PATH
@@ -100,6 +120,35 @@ SOURCE_FILE
               R_CURLY "}"
           SEMICOLON ";"
         WHITESPACE "\n    "
+        EXPR_STMT
+          RECORD_EXPR
+            PATH
+              PATH_SEGMENT
+                NAME_REF
+                  IDENT "S"
+            WHITESPACE " "
+            RECORD_EXPR_FIELD_LIST
+              L_CURLY "{"
+              WHITESPACE " "
+              RECORD_EXPR_FIELD
+                NAME_REF
+                  IDENT "x"
+                COLON ":"
+                WHITESPACE " "
+                CALL_EXPR
+                  PATH_EXPR
+                    PATH
+                      PATH_SEGMENT
+                        COLON2 "::"
+                        NAME_REF
+                          IDENT "default"
+                  ARG_LIST
+                    L_PAREN "("
+                    R_PAREN ")"
+              WHITESPACE " "
+              R_CURLY "}"
+          SEMICOLON ";"
+        WHITESPACE "\n    "
         EXPR_STMT
           RECORD_EXPR
             PATH

crates/parser/test_data/parser/inline/ok/0061_record_lit.rs

@@ -1,6 +1,8 @@
 fn foo() {
     S {};
+    S { x };
     S { x, y: 32, };
     S { x, y: 32, ..Default::default() };
+    S { x: ::default() };
     TupleStruct { 0: 1 };
 }

crates/parser/test_data/parser/inline/ok/0166_half_open_range_pat.rast

@@ -11,7 +11,7 @@ SOURCE_FILE
     BLOCK_EXPR
       STMT_LIST
         L_CURLY "{"
-        WHITESPACE " "
+        WHITESPACE "\n    "
         LET_STMT
           LET_KW "let"
           WHITESPACE " "
@@ -27,6 +27,25 @@ SOURCE_FILE
           LITERAL
             INT_NUMBER "1u32"
           SEMICOLON ";"
-        WHITESPACE " "
+        WHITESPACE "\n    "
+        LET_STMT
+          LET_KW "let"
+          WHITESPACE " "
+          RANGE_PAT
+            LITERAL_PAT
+              LITERAL
+                INT_NUMBER "0"
+            DOT2 ".."
+          COLON ":"
+          WHITESPACE " "
+          INFER_TYPE
+            UNDERSCORE "_"
+          WHITESPACE " "
+          EQ "="
+          WHITESPACE " "
+          LITERAL
+            INT_NUMBER "1u32"
+          SEMICOLON ";"
+        WHITESPACE "\n"
         R_CURLY "}"
   WHITESPACE "\n"

crates/parser/test_data/parser/inline/ok/0166_half_open_range_pat.rs

@@ -1 +1,4 @@
-fn f() { let 0 .. = 1u32; }
+fn f() {
+    let 0 .. = 1u32;
+    let 0..: _ = 1u32;
+}

crates/proc-macro-api/src/msg/flat.rs

@@ -35,10 +35,7 @@
 //! as we don't have bincode in Cargo.toml yet, lets stick with serde_json for
 //! the time being.
 
-use std::{
-    collections::{HashMap, VecDeque},
-    convert::TryInto,
-};
+use std::collections::{HashMap, VecDeque};
 
 use serde::{Deserialize, Serialize};
 use tt::TokenId;

crates/proc-macro-srv/src/abis/abi_1_58/proc_macro/mod.rs

@@ -157,7 +157,7 @@ impl From<TokenTree> for TokenStream {
 }
 
 /// Collects a number of token trees into a single stream.
-impl iter::FromIterator<TokenTree> for TokenStream {
+impl FromIterator<TokenTree> for TokenStream {
     fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self {
         trees.into_iter().map(TokenStream::from).collect()
     }
@@ -165,7 +165,7 @@ impl iter::FromIterator<TokenTree> for TokenStream {
 
 /// A "flattening" operation on token streams, collects token trees
 /// from multiple token streams into a single stream.
-impl iter::FromIterator<TokenStream> for TokenStream {
+impl FromIterator<TokenStream> for TokenStream {
     fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self {
         let mut builder = bridge::client::TokenStreamBuilder::new();
         streams.into_iter().for_each(|stream| builder.push(stream.0));

crates/proc-macro-srv/src/abis/abi_1_58/ra_server.rs

@@ -12,7 +12,6 @@ use super::proc_macro::bridge::{self, server};
 
 use std::collections::HashMap;
 use std::hash::Hash;
-use std::iter::FromIterator;
 use std::ops::Bound;
 use std::{ascii, vec::IntoIter};
 

crates/proc-macro-srv/src/abis/abi_1_63/proc_macro/mod.rs

@@ -207,7 +207,7 @@ impl ConcatStreamsHelper {
 }
 
 /// Collects a number of token trees into a single stream.
-impl iter::FromIterator<TokenTree> for TokenStream {
+impl FromIterator<TokenTree> for TokenStream {
     fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self {
         trees.into_iter().map(TokenStream::from).collect()
     }
@@ -215,7 +215,7 @@ impl iter::FromIterator<TokenTree> for TokenStream {
 
 /// A "flattening" operation on token streams, collects token trees
 /// from multiple token streams into a single stream.
-impl iter::FromIterator<TokenStream> for TokenStream {
+impl FromIterator<TokenStream> for TokenStream {
     fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self {
         let iter = streams.into_iter();
         let mut builder = ConcatStreamsHelper::new(iter.size_hint().0);

crates/proc-macro-srv/src/abis/abi_1_63/ra_server.rs

@@ -12,7 +12,6 @@ use super::proc_macro::bridge::{self, server};
 
 use std::collections::HashMap;
 use std::hash::Hash;
-use std::iter::FromIterator;
 use std::ops::Bound;
 use std::{ascii, vec::IntoIter};
 

crates/proc-macro-srv/src/abis/abi_1_64/mod.rs

@@ -1,105 +0,0 @@
-//! Proc macro ABI.
-
-#[allow(dead_code)]
-#[doc(hidden)]
-mod proc_macro;
-
-#[allow(dead_code)]
-#[doc(hidden)]
-mod ra_server;
-
-use libloading::Library;
-use proc_macro_api::ProcMacroKind;
-
-use super::PanicMessage;
-
-pub use ra_server::TokenStream;
-
-pub(crate) struct Abi {
-    exported_macros: Vec<proc_macro::bridge::client::ProcMacro>,
-}
-
-impl From<proc_macro::bridge::PanicMessage> for PanicMessage {
-    fn from(p: proc_macro::bridge::PanicMessage) -> Self {
-        Self { message: p.as_str().map(|s| s.to_string()) }
-    }
-}
-
-impl Abi {
-    pub unsafe fn from_lib(lib: &Library, symbol_name: String) -> Result<Abi, libloading::Error> {
-        let macros: libloading::Symbol<'_, &&[proc_macro::bridge::client::ProcMacro]> =
-            lib.get(symbol_name.as_bytes())?;
-        Ok(Self { exported_macros: macros.to_vec() })
-    }
-
-    pub fn expand(
-        &self,
-        macro_name: &str,
-        macro_body: &tt::Subtree,
-        attributes: Option<&tt::Subtree>,
-    ) -> Result<tt::Subtree, PanicMessage> {
-        let parsed_body = TokenStream::with_subtree(macro_body.clone());
-
-        let parsed_attributes =
-            attributes.map_or(TokenStream::new(), |attr| TokenStream::with_subtree(attr.clone()));
-
-        for proc_macro in &self.exported_macros {
-            match proc_macro {
-                proc_macro::bridge::client::ProcMacro::CustomDerive {
-                    trait_name, client, ..
-                } if *trait_name == macro_name => {
-                    let res = client.run(
-                        &proc_macro::bridge::server::SameThread,
-                        ra_server::RustAnalyzer::default(),
-                        parsed_body,
-                        true,
-                    );
-                    return res.map(|it| it.into_subtree()).map_err(PanicMessage::from);
-                }
-                proc_macro::bridge::client::ProcMacro::Bang { name, client }
-                    if *name == macro_name =>
-                {
-                    let res = client.run(
-                        &proc_macro::bridge::server::SameThread,
-                        ra_server::RustAnalyzer::default(),
-                        parsed_body,
-                        true,
-                    );
-                    return res.map(|it| it.into_subtree()).map_err(PanicMessage::from);
-                }
-                proc_macro::bridge::client::ProcMacro::Attr { name, client }
-                    if *name == macro_name =>
-                {
-                    let res = client.run(
-                        &proc_macro::bridge::server::SameThread,
-                        ra_server::RustAnalyzer::default(),
-                        parsed_attributes,
-                        parsed_body,
-                        true,
-                    );
-                    return res.map(|it| it.into_subtree()).map_err(PanicMessage::from);
-                }
-                _ => continue,
-            }
-        }
-
-        Err(proc_macro::bridge::PanicMessage::String("Nothing to expand".to_string()).into())
-    }
-
-    pub fn list_macros(&self) -> Vec<(String, ProcMacroKind)> {
-        self.exported_macros
-            .iter()
-            .map(|proc_macro| match proc_macro {
-                proc_macro::bridge::client::ProcMacro::CustomDerive { trait_name, .. } => {
-                    (trait_name.to_string(), ProcMacroKind::CustomDerive)
-                }
-                proc_macro::bridge::client::ProcMacro::Bang { name, .. } => {
-                    (name.to_string(), ProcMacroKind::FuncLike)
-                }
-                proc_macro::bridge::client::ProcMacro::Attr { name, .. } => {
-                    (name.to_string(), ProcMacroKind::Attr)
-                }
-            })
-            .collect()
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/buffer.rs

@@ -1,156 +0,0 @@
-//! Buffer management for same-process client<->server communication.
-
-use std::io::{self, Write};
-use std::mem;
-use std::ops::{Deref, DerefMut};
-use std::slice;
-
-#[repr(C)]
-pub struct Buffer {
-    data: *mut u8,
-    len: usize,
-    capacity: usize,
-    reserve: extern "C" fn(Buffer, usize) -> Buffer,
-    drop: extern "C" fn(Buffer),
-}
-
-unsafe impl Sync for Buffer {}
-unsafe impl Send for Buffer {}
-
-impl Default for Buffer {
-    #[inline]
-    fn default() -> Self {
-        Self::from(vec![])
-    }
-}
-
-impl Deref for Buffer {
-    type Target = [u8];
-    #[inline]
-    fn deref(&self) -> &[u8] {
-        unsafe { slice::from_raw_parts(self.data as *const u8, self.len) }
-    }
-}
-
-impl DerefMut for Buffer {
-    #[inline]
-    fn deref_mut(&mut self) -> &mut [u8] {
-        unsafe { slice::from_raw_parts_mut(self.data, self.len) }
-    }
-}
-
-impl Buffer {
-    #[inline]
-    pub(super) fn new() -> Self {
-        Self::default()
-    }
-
-    #[inline]
-    pub(super) fn clear(&mut self) {
-        self.len = 0;
-    }
-
-    #[inline]
-    pub(super) fn take(&mut self) -> Self {
-        mem::take(self)
-    }
-
-    // We have the array method separate from extending from a slice. This is
-    // because in the case of small arrays, codegen can be more efficient
-    // (avoiding a memmove call). With extend_from_slice, LLVM at least
-    // currently is not able to make that optimization.
-    #[inline]
-    pub(super) fn extend_from_array<const N: usize>(&mut self, xs: &[u8; N]) {
-        if xs.len() > (self.capacity - self.len) {
-            let b = self.take();
-            *self = (b.reserve)(b, xs.len());
-        }
-        unsafe {
-            xs.as_ptr().copy_to_nonoverlapping(self.data.add(self.len), xs.len());
-            self.len += xs.len();
-        }
-    }
-
-    #[inline]
-    pub(super) fn extend_from_slice(&mut self, xs: &[u8]) {
-        if xs.len() > (self.capacity - self.len) {
-            let b = self.take();
-            *self = (b.reserve)(b, xs.len());
-        }
-        unsafe {
-            xs.as_ptr().copy_to_nonoverlapping(self.data.add(self.len), xs.len());
-            self.len += xs.len();
-        }
-    }
-
-    #[inline]
-    pub(super) fn push(&mut self, v: u8) {
-        // The code here is taken from Vec::push, and we know that reserve()
-        // will panic if we're exceeding isize::MAX bytes and so there's no need
-        // to check for overflow.
-        if self.len == self.capacity {
-            let b = self.take();
-            *self = (b.reserve)(b, 1);
-        }
-        unsafe {
-            *self.data.add(self.len) = v;
-            self.len += 1;
-        }
-    }
-}
-
-impl Write for Buffer {
-    #[inline]
-    fn write(&mut self, xs: &[u8]) -> io::Result<usize> {
-        self.extend_from_slice(xs);
-        Ok(xs.len())
-    }
-
-    #[inline]
-    fn write_all(&mut self, xs: &[u8]) -> io::Result<()> {
-        self.extend_from_slice(xs);
-        Ok(())
-    }
-
-    #[inline]
-    fn flush(&mut self) -> io::Result<()> {
-        Ok(())
-    }
-}
-
-impl Drop for Buffer {
-    #[inline]
-    fn drop(&mut self) {
-        let b = self.take();
-        (b.drop)(b);
-    }
-}
-
-impl From<Vec<u8>> for Buffer {
-    fn from(mut v: Vec<u8>) -> Self {
-        let (data, len, capacity) = (v.as_mut_ptr(), v.len(), v.capacity());
-        mem::forget(v);
-
-        // This utility function is nested in here because it can *only*
-        // be safely called on `Buffer`s created by *this* `proc_macro`.
-        fn to_vec(b: Buffer) -> Vec<u8> {
-            unsafe {
-                let Buffer { data, len, capacity, .. } = b;
-                mem::forget(b);
-                Vec::from_raw_parts(data, len, capacity)
-            }
-        }
-
-        extern "C" fn reserve(b: Buffer, additional: usize) -> Buffer {
-            let mut v = to_vec(b);
-            v.reserve(additional);
-            Buffer::from(v)
-        }
-
-        extern "C" fn drop(b: Buffer) {
-            mem::drop(to_vec(b));
-        }
-
-        Buffer { data, len, capacity, reserve, drop }
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/client.rs

@@ -1,529 +0,0 @@
-//! Client-side types.
-
-use super::*;
-
-use std::marker::PhantomData;
-
-macro_rules! define_handles {
-    (
-        'owned: $($oty:ident,)*
-        'interned: $($ity:ident,)*
-    ) => {
-        #[repr(C)]
-        #[allow(non_snake_case)]
-        pub struct HandleCounters {
-            $($oty: AtomicUsize,)*
-            $($ity: AtomicUsize,)*
-        }
-
-        impl HandleCounters {
-            // FIXME(eddyb) use a reference to the `static COUNTERS`, instead of
-            // a wrapper `fn` pointer, once `const fn` can reference `static`s.
-            extern "C" fn get() -> &'static Self {
-                static COUNTERS: HandleCounters = HandleCounters {
-                    $($oty: AtomicUsize::new(1),)*
-                    $($ity: AtomicUsize::new(1),)*
-                };
-                &COUNTERS
-            }
-        }
-
-        // FIXME(eddyb) generate the definition of `HandleStore` in `server.rs`.
-        #[repr(C)]
-        #[allow(non_snake_case)]
-        pub(super) struct HandleStore<S: server::Types> {
-            $($oty: handle::OwnedStore<S::$oty>,)*
-            $($ity: handle::InternedStore<S::$ity>,)*
-        }
-
-        impl<S: server::Types> HandleStore<S> {
-            pub(super) fn new(handle_counters: &'static HandleCounters) -> Self {
-                HandleStore {
-                    $($oty: handle::OwnedStore::new(&handle_counters.$oty),)*
-                    $($ity: handle::InternedStore::new(&handle_counters.$ity),)*
-                }
-            }
-        }
-
-        $(
-            #[repr(C)]
-            pub(crate) struct $oty {
-                handle: handle::Handle,
-                // Prevent Send and Sync impls. `!Send`/`!Sync` is the usual
-                // way of doing this, but that requires unstable features.
-                // rust-analyzer uses this code and avoids unstable features.
-                _marker: PhantomData<*mut ()>,
-            }
-
-            // Forward `Drop::drop` to the inherent `drop` method.
-            impl Drop for $oty {
-                fn drop(&mut self) {
-                    $oty {
-                        handle: self.handle,
-                        _marker: PhantomData,
-                    }.drop();
-                }
-            }
-
-            impl<S> Encode<S> for $oty {
-                fn encode(self, w: &mut Writer, s: &mut S) {
-                    let handle = self.handle;
-                    mem::forget(self);
-                    handle.encode(w, s);
-                }
-            }
-
-            impl<S: server::Types> DecodeMut<'_, '_, HandleStore<server::MarkedTypes<S>>>
-                for Marked<S::$oty, $oty>
-            {
-                fn decode(r: &mut Reader<'_>, s: &mut HandleStore<server::MarkedTypes<S>>) -> Self {
-                    s.$oty.take(handle::Handle::decode(r, &mut ()))
-                }
-            }
-
-            impl<S> Encode<S> for &$oty {
-                fn encode(self, w: &mut Writer, s: &mut S) {
-                    self.handle.encode(w, s);
-                }
-            }
-
-            impl<'s, S: server::Types> Decode<'_, 's, HandleStore<server::MarkedTypes<S>>>
-                for &'s Marked<S::$oty, $oty>
-            {
-                fn decode(r: &mut Reader<'_>, s: &'s HandleStore<server::MarkedTypes<S>>) -> Self {
-                    &s.$oty[handle::Handle::decode(r, &mut ())]
-                }
-            }
-
-            impl<S> Encode<S> for &mut $oty {
-                fn encode(self, w: &mut Writer, s: &mut S) {
-                    self.handle.encode(w, s);
-                }
-            }
-
-            impl<'s, S: server::Types> DecodeMut<'_, 's, HandleStore<server::MarkedTypes<S>>>
-                for &'s mut Marked<S::$oty, $oty>
-            {
-                fn decode(
-                    r: &mut Reader<'_>,
-                    s: &'s mut HandleStore<server::MarkedTypes<S>>
-                ) -> Self {
-                    &mut s.$oty[handle::Handle::decode(r, &mut ())]
-                }
-            }
-
-            impl<S: server::Types> Encode<HandleStore<server::MarkedTypes<S>>>
-                for Marked<S::$oty, $oty>
-            {
-                fn encode(self, w: &mut Writer, s: &mut HandleStore<server::MarkedTypes<S>>) {
-                    s.$oty.alloc(self).encode(w, s);
-                }
-            }
-
-            impl<S> DecodeMut<'_, '_, S> for $oty {
-                fn decode(r: &mut Reader<'_>, s: &mut S) -> Self {
-                    $oty {
-                        handle: handle::Handle::decode(r, s),
-                        _marker: PhantomData,
-                    }
-                }
-            }
-        )*
-
-        $(
-            #[repr(C)]
-            #[derive(Copy, Clone, PartialEq, Eq, Hash)]
-            pub(crate) struct $ity {
-                handle: handle::Handle,
-                // Prevent Send and Sync impls. `!Send`/`!Sync` is the usual
-                // way of doing this, but that requires unstable features.
-                // rust-analyzer uses this code and avoids unstable features.
-                _marker: PhantomData<*mut ()>,
-            }
-
-            impl<S> Encode<S> for $ity {
-                fn encode(self, w: &mut Writer, s: &mut S) {
-                    self.handle.encode(w, s);
-                }
-            }
-
-            impl<S: server::Types> DecodeMut<'_, '_, HandleStore<server::MarkedTypes<S>>>
-                for Marked<S::$ity, $ity>
-            {
-                fn decode(r: &mut Reader<'_>, s: &mut HandleStore<server::MarkedTypes<S>>) -> Self {
-                    s.$ity.copy(handle::Handle::decode(r, &mut ()))
-                }
-            }
-
-            impl<S: server::Types> Encode<HandleStore<server::MarkedTypes<S>>>
-                for Marked<S::$ity, $ity>
-            {
-                fn encode(self, w: &mut Writer, s: &mut HandleStore<server::MarkedTypes<S>>) {
-                    s.$ity.alloc(self).encode(w, s);
-                }
-            }
-
-            impl<S> DecodeMut<'_, '_, S> for $ity {
-                fn decode(r: &mut Reader<'_>, s: &mut S) -> Self {
-                    $ity {
-                        handle: handle::Handle::decode(r, s),
-                        _marker: PhantomData,
-                    }
-                }
-            }
-        )*
-    }
-}
-define_handles! {
-    'owned:
-    FreeFunctions,
-    TokenStream,
-    Literal,
-    SourceFile,
-    MultiSpan,
-    Diagnostic,
-
-    'interned:
-    Ident,
-    Span,
-}
-
-// FIXME(eddyb) generate these impls by pattern-matching on the
-// names of methods - also could use the presence of `fn drop`
-// to distinguish between 'owned and 'interned, above.
-// Alternatively, special "modes" could be listed of types in with_api
-// instead of pattern matching on methods, here and in server decl.
-
-impl Clone for TokenStream {
-    fn clone(&self) -> Self {
-        self.clone()
-    }
-}
-
-impl Clone for Literal {
-    fn clone(&self) -> Self {
-        self.clone()
-    }
-}
-
-impl fmt::Debug for Literal {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_struct("Literal")
-            // format the kind without quotes, as in `kind: Float`
-            .field("kind", &format_args!("{}", &self.debug_kind()))
-            .field("symbol", &self.symbol())
-            // format `Some("...")` on one line even in {:#?} mode
-            .field("suffix", &format_args!("{:?}", &self.suffix()))
-            .field("span", &self.span())
-            .finish()
-    }
-}
-
-impl Clone for SourceFile {
-    fn clone(&self) -> Self {
-        self.clone()
-    }
-}
-
-impl Span {
-    pub(crate) fn def_site() -> Span {
-        Bridge::with(|bridge| bridge.globals.def_site)
-    }
-
-    pub(crate) fn call_site() -> Span {
-        Bridge::with(|bridge| bridge.globals.call_site)
-    }
-
-    pub(crate) fn mixed_site() -> Span {
-        Bridge::with(|bridge| bridge.globals.mixed_site)
-    }
-}
-
-impl fmt::Debug for Span {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.write_str(&self.debug())
-    }
-}
-
-macro_rules! define_client_side {
-    ($($name:ident {
-        $(fn $method:ident($($arg:ident: $arg_ty:ty),* $(,)?) $(-> $ret_ty:ty)*;)*
-    }),* $(,)?) => {
-        $(impl $name {
-            $(pub(crate) fn $method($($arg: $arg_ty),*) $(-> $ret_ty)* {
-                Bridge::with(|bridge| {
-                    let mut buf = bridge.cached_buffer.take();
-
-                    buf.clear();
-                    api_tags::Method::$name(api_tags::$name::$method).encode(&mut buf, &mut ());
-                    reverse_encode!(buf; $($arg),*);
-
-                    buf = bridge.dispatch.call(buf);
-
-                    let r = Result::<_, PanicMessage>::decode(&mut &buf[..], &mut ());
-
-                    bridge.cached_buffer = buf;
-
-                    r.unwrap_or_else(|e| panic::resume_unwind(e.into()))
-                })
-            })*
-        })*
-    }
-}
-with_api!(self, self, define_client_side);
-
-struct Bridge<'a> {
-    /// Reusable buffer (only `clear`-ed, never shrunk), primarily
-    /// used for making requests.
-    cached_buffer: Buffer,
-
-    /// Server-side function that the client uses to make requests.
-    dispatch: closure::Closure<'a, Buffer, Buffer>,
-
-    /// Provided globals for this macro expansion.
-    globals: ExpnGlobals<Span>,
-}
-
-enum BridgeState<'a> {
-    /// No server is currently connected to this client.
-    NotConnected,
-
-    /// A server is connected and available for requests.
-    Connected(Bridge<'a>),
-
-    /// Access to the bridge is being exclusively acquired
-    /// (e.g., during `BridgeState::with`).
-    InUse,
-}
-
-enum BridgeStateL {}
-
-impl<'a> scoped_cell::ApplyL<'a> for BridgeStateL {
-    type Out = BridgeState<'a>;
-}
-
-thread_local! {
-    static BRIDGE_STATE: scoped_cell::ScopedCell<BridgeStateL> =
-        scoped_cell::ScopedCell::new(BridgeState::NotConnected);
-}
-
-impl BridgeState<'_> {
-    /// Take exclusive control of the thread-local
-    /// `BridgeState`, and pass it to `f`, mutably.
-    /// The state will be restored after `f` exits, even
-    /// by panic, including modifications made to it by `f`.
-    ///
-    /// N.B., while `f` is running, the thread-local state
-    /// is `BridgeState::InUse`.
-    fn with<R>(f: impl FnOnce(&mut BridgeState<'_>) -> R) -> R {
-        BRIDGE_STATE.with(|state| {
-            state.replace(BridgeState::InUse, |mut state| {
-                // FIXME(#52812) pass `f` directly to `replace` when `RefMutL` is gone
-                f(&mut *state)
-            })
-        })
-    }
-}
-
-impl Bridge<'_> {
-    fn with<R>(f: impl FnOnce(&mut Bridge<'_>) -> R) -> R {
-        BridgeState::with(|state| match state {
-            BridgeState::NotConnected => {
-                panic!("procedural macro API is used outside of a procedural macro");
-            }
-            BridgeState::InUse => {
-                panic!("procedural macro API is used while it's already in use");
-            }
-            BridgeState::Connected(bridge) => f(bridge),
-        })
-    }
-}
-
-pub(crate) fn is_available() -> bool {
-    BridgeState::with(|state| match state {
-        BridgeState::Connected(_) | BridgeState::InUse => true,
-        BridgeState::NotConnected => false,
-    })
-}
-
-/// A client-side RPC entry-point, which may be using a different `proc_macro`
-/// from the one used by the server, but can be invoked compatibly.
-///
-/// Note that the (phantom) `I` ("input") and `O` ("output") type parameters
-/// decorate the `Client<I, O>` with the RPC "interface" of the entry-point, but
-/// do not themselves participate in ABI, at all, only facilitate type-checking.
-///
-/// E.g. `Client<TokenStream, TokenStream>` is the common proc macro interface,
-/// used for `#[proc_macro] fn foo(input: TokenStream) -> TokenStream`,
-/// indicating that the RPC input and output will be serialized token streams,
-/// and forcing the use of APIs that take/return `S::TokenStream`, server-side.
-#[repr(C)]
-pub struct Client<I, O> {
-    // FIXME(eddyb) use a reference to the `static COUNTERS`, instead of
-    // a wrapper `fn` pointer, once `const fn` can reference `static`s.
-    pub(super) get_handle_counters: extern "C" fn() -> &'static HandleCounters,
-
-    pub(super) run: extern "C" fn(BridgeConfig<'_>) -> Buffer,
-
-    pub(super) _marker: PhantomData<fn(I) -> O>,
-}
-
-impl<I, O> Copy for Client<I, O> {}
-impl<I, O> Clone for Client<I, O> {
-    fn clone(&self) -> Self {
-        *self
-    }
-}
-
-fn maybe_install_panic_hook(force_show_panics: bool) {
-    // Hide the default panic output within `proc_macro` expansions.
-    // NB. the server can't do this because it may use a different libstd.
-    static HIDE_PANICS_DURING_EXPANSION: Once = Once::new();
-    HIDE_PANICS_DURING_EXPANSION.call_once(|| {
-        let prev = panic::take_hook();
-        panic::set_hook(Box::new(move |info| {
-            let show = BridgeState::with(|state| match state {
-                BridgeState::NotConnected => true,
-                BridgeState::Connected(_) | BridgeState::InUse => force_show_panics,
-            });
-            if show {
-                prev(info)
-            }
-        }));
-    });
-}
-
-/// Client-side helper for handling client panics, entering the bridge,
-/// deserializing input and serializing output.
-// FIXME(eddyb) maybe replace `Bridge::enter` with this?
-fn run_client<A: for<'a, 's> DecodeMut<'a, 's, ()>, R: Encode<()>>(
-    config: BridgeConfig<'_>,
-    f: impl FnOnce(A) -> R,
-) -> Buffer {
-    let BridgeConfig { input: mut buf, dispatch, force_show_panics, .. } = config;
-
-    panic::catch_unwind(panic::AssertUnwindSafe(|| {
-        maybe_install_panic_hook(force_show_panics);
-
-        let reader = &mut &buf[..];
-        let (globals, input) = <(ExpnGlobals<Span>, A)>::decode(reader, &mut ());
-
-        // Put the buffer we used for input back in the `Bridge` for requests.
-        let new_state =
-            BridgeState::Connected(Bridge { cached_buffer: buf.take(), dispatch, globals });
-
-        BRIDGE_STATE.with(|state| {
-            state.set(new_state, || {
-                let output = f(input);
-
-                // Take the `cached_buffer` back out, for the output value.
-                buf = Bridge::with(|bridge| bridge.cached_buffer.take());
-
-                // HACK(eddyb) Separate encoding a success value (`Ok(output)`)
-                // from encoding a panic (`Err(e: PanicMessage)`) to avoid
-                // having handles outside the `bridge.enter(|| ...)` scope, and
-                // to catch panics that could happen while encoding the success.
-                //
-                // Note that panics should be impossible beyond this point, but
-                // this is defensively trying to avoid any accidental panicking
-                // reaching the `extern "C"` (which should `abort` but might not
-                // at the moment, so this is also potentially preventing UB).
-                buf.clear();
-                Ok::<_, ()>(output).encode(&mut buf, &mut ());
-            })
-        })
-    }))
-    .map_err(PanicMessage::from)
-    .unwrap_or_else(|e| {
-        buf.clear();
-        Err::<(), _>(e).encode(&mut buf, &mut ());
-    });
-    buf
-}
-
-impl Client<super::super::TokenStream, super::super::TokenStream> {
-    pub const fn expand1(
-        f: impl Fn(super::super::TokenStream) -> super::super::TokenStream + Copy,
-    ) -> Self {
-        Client {
-            get_handle_counters: HandleCounters::get,
-            run: super::selfless_reify::reify_to_extern_c_fn_hrt_bridge(move |bridge| {
-                run_client(bridge, |input| f(super::super::TokenStream(input)).0)
-            }),
-            _marker: PhantomData,
-        }
-    }
-}
-
-impl Client<(super::super::TokenStream, super::super::TokenStream), super::super::TokenStream> {
-    pub const fn expand2(
-        f: impl Fn(super::super::TokenStream, super::super::TokenStream) -> super::super::TokenStream
-            + Copy,
-    ) -> Self {
-        Client {
-            get_handle_counters: HandleCounters::get,
-            run: super::selfless_reify::reify_to_extern_c_fn_hrt_bridge(move |bridge| {
-                run_client(bridge, |(input, input2)| {
-                    f(super::super::TokenStream(input), super::super::TokenStream(input2)).0
-                })
-            }),
-            _marker: PhantomData,
-        }
-    }
-}
-
-#[repr(C)]
-#[derive(Copy, Clone)]
-pub enum ProcMacro {
-    CustomDerive {
-        trait_name: &'static str,
-        attributes: &'static [&'static str],
-        client: Client<super::super::TokenStream, super::super::TokenStream>,
-    },
-
-    Attr {
-        name: &'static str,
-        client: Client<
-            (super::super::TokenStream, super::super::TokenStream),
-            super::super::TokenStream,
-        >,
-    },
-
-    Bang {
-        name: &'static str,
-        client: Client<super::super::TokenStream, super::super::TokenStream>,
-    },
-}
-
-impl ProcMacro {
-    pub fn name(&self) -> &'static str {
-        match self {
-            ProcMacro::CustomDerive { trait_name, .. } => trait_name,
-            ProcMacro::Attr { name, .. } => name,
-            ProcMacro::Bang { name, .. } => name,
-        }
-    }
-
-    pub const fn custom_derive(
-        trait_name: &'static str,
-        attributes: &'static [&'static str],
-        expand: impl Fn(super::super::TokenStream) -> super::super::TokenStream + Copy,
-    ) -> Self {
-        ProcMacro::CustomDerive { trait_name, attributes, client: Client::expand1(expand) }
-    }
-
-    pub const fn attr(
-        name: &'static str,
-        expand: impl Fn(super::super::TokenStream, super::super::TokenStream) -> super::super::TokenStream
-            + Copy,
-    ) -> Self {
-        ProcMacro::Attr { name, client: Client::expand2(expand) }
-    }
-
-    pub const fn bang(
-        name: &'static str,
-        expand: impl Fn(super::super::TokenStream) -> super::super::TokenStream + Copy,
-    ) -> Self {
-        ProcMacro::Bang { name, client: Client::expand1(expand) }
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/closure.rs

@@ -1,32 +0,0 @@
-//! Closure type (equivalent to `&mut dyn FnMut(A) -> R`) that's `repr(C)`.
-
-use std::marker::PhantomData;
-
-#[repr(C)]
-pub struct Closure<'a, A, R> {
-    call: unsafe extern "C" fn(*mut Env, A) -> R,
-    env: *mut Env,
-    // Prevent Send and Sync impls. `!Send`/`!Sync` is the usual way of doing
-    // this, but that requires unstable features. rust-analyzer uses this code
-    // and avoids unstable features.
-    //
-    // The `'a` lifetime parameter represents the lifetime of `Env`.
-    _marker: PhantomData<*mut &'a mut ()>,
-}
-
-struct Env;
-
-impl<'a, A, R, F: FnMut(A) -> R> From<&'a mut F> for Closure<'a, A, R> {
-    fn from(f: &'a mut F) -> Self {
-        unsafe extern "C" fn call<A, R, F: FnMut(A) -> R>(env: *mut Env, arg: A) -> R {
-            (*(env as *mut _ as *mut F))(arg)
-        }
-        Closure { call: call::<A, R, F>, env: f as *mut _ as *mut Env, _marker: PhantomData }
-    }
-}
-
-impl<'a, A, R> Closure<'a, A, R> {
-    pub fn call(&mut self, arg: A) -> R {
-        unsafe { (self.call)(self.env, arg) }
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/handle.rs

@@ -1,89 +0,0 @@
-//! Server-side handles and storage for per-handle data.
-
-use std::collections::{BTreeMap, HashMap};
-use std::hash::{BuildHasher, Hash};
-use std::num::NonZeroU32;
-use std::ops::{Index, IndexMut};
-use std::sync::atomic::{AtomicUsize, Ordering};
-
-pub(super) type Handle = NonZeroU32;
-
-/// A store that associates values of type `T` with numeric handles. A value can
-/// be looked up using its handle.
-pub(super) struct OwnedStore<T: 'static> {
-    counter: &'static AtomicUsize,
-    data: BTreeMap<Handle, T>,
-}
-
-impl<T> OwnedStore<T> {
-    pub(super) fn new(counter: &'static AtomicUsize) -> Self {
-        // Ensure the handle counter isn't 0, which would panic later,
-        // when `NonZeroU32::new` (aka `Handle::new`) is called in `alloc`.
-        assert_ne!(counter.load(Ordering::SeqCst), 0);
-
-        OwnedStore { counter, data: BTreeMap::new() }
-    }
-}
-
-impl<T> OwnedStore<T> {
-    pub(super) fn alloc(&mut self, x: T) -> Handle {
-        let counter = self.counter.fetch_add(1, Ordering::SeqCst);
-        let handle = Handle::new(counter as u32).expect("`proc_macro` handle counter overflowed");
-        assert!(self.data.insert(handle, x).is_none());
-        handle
-    }
-
-    pub(super) fn take(&mut self, h: Handle) -> T {
-        self.data.remove(&h).expect("use-after-free in `proc_macro` handle")
-    }
-}
-
-impl<T> Index<Handle> for OwnedStore<T> {
-    type Output = T;
-    fn index(&self, h: Handle) -> &T {
-        self.data.get(&h).expect("use-after-free in `proc_macro` handle")
-    }
-}
-
-impl<T> IndexMut<Handle> for OwnedStore<T> {
-    fn index_mut(&mut self, h: Handle) -> &mut T {
-        self.data.get_mut(&h).expect("use-after-free in `proc_macro` handle")
-    }
-}
-
-// HACK(eddyb) deterministic `std::collections::hash_map::RandomState` replacement
-// that doesn't require adding any dependencies to `proc_macro` (like `rustc-hash`).
-#[derive(Clone)]
-struct NonRandomState;
-
-impl BuildHasher for NonRandomState {
-    type Hasher = std::collections::hash_map::DefaultHasher;
-    #[inline]
-    fn build_hasher(&self) -> Self::Hasher {
-        Self::Hasher::new()
-    }
-}
-
-/// Like `OwnedStore`, but avoids storing any value more than once.
-pub(super) struct InternedStore<T: 'static> {
-    owned: OwnedStore<T>,
-    interner: HashMap<T, Handle, NonRandomState>,
-}
-
-impl<T: Copy + Eq + Hash> InternedStore<T> {
-    pub(super) fn new(counter: &'static AtomicUsize) -> Self {
-        InternedStore {
-            owned: OwnedStore::new(counter),
-            interner: HashMap::with_hasher(NonRandomState),
-        }
-    }
-
-    pub(super) fn alloc(&mut self, x: T) -> Handle {
-        let owned = &mut self.owned;
-        *self.interner.entry(x).or_insert_with(|| owned.alloc(x))
-    }
-
-    pub(super) fn copy(&mut self, h: Handle) -> T {
-        self.owned[h]
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/mod.rs

@@ -1,493 +0,0 @@
-//! Internal interface for communicating between a `proc_macro` client
-//! (a proc macro crate) and a `proc_macro` server (a compiler front-end).
-//!
-//! Serialization (with C ABI buffers) and unique integer handles are employed
-//! to allow safely interfacing between two copies of `proc_macro` built
-//! (from the same source) by different compilers with potentially mismatching
-//! Rust ABIs (e.g., stage0/bin/rustc vs stage1/bin/rustc during bootstrap).
-
-#![deny(unsafe_code)]
-
-pub use super::{Delimiter, Level, LineColumn, Spacing};
-use std::fmt;
-use std::hash::Hash;
-use std::marker;
-use std::mem;
-use std::ops::Bound;
-use std::panic;
-use std::sync::atomic::AtomicUsize;
-use std::sync::Once;
-use std::thread;
-
-/// Higher-order macro describing the server RPC API, allowing automatic
-/// generation of type-safe Rust APIs, both client-side and server-side.
-///
-/// `with_api!(MySelf, my_self, my_macro)` expands to:
-/// ```rust,ignore (pseudo-code)
-/// my_macro! {
-///     // ...
-///     Literal {
-///         // ...
-///         fn character(ch: char) -> MySelf::Literal;
-///         // ...
-///         fn span(my_self: &MySelf::Literal) -> MySelf::Span;
-///         fn set_span(my_self: &mut MySelf::Literal, span: MySelf::Span);
-///     },
-///     // ...
-/// }
-/// ```
-///
-/// The first two arguments serve to customize the arguments names
-/// and argument/return types, to enable several different usecases:
-///
-/// If `my_self` is just `self`, then each `fn` signature can be used
-/// as-is for a method. If it's anything else (`self_` in practice),
-/// then the signatures don't have a special `self` argument, and
-/// can, therefore, have a different one introduced.
-///
-/// If `MySelf` is just `Self`, then the types are only valid inside
-/// a trait or a trait impl, where the trait has associated types
-/// for each of the API types. If non-associated types are desired,
-/// a module name (`self` in practice) can be used instead of `Self`.
-macro_rules! with_api {
-    ($S:ident, $self:ident, $m:ident) => {
-        $m! {
-            FreeFunctions {
-                fn drop($self: $S::FreeFunctions);
-                fn track_env_var(var: &str, value: Option<&str>);
-                fn track_path(path: &str);
-            },
-            TokenStream {
-                fn drop($self: $S::TokenStream);
-                fn clone($self: &$S::TokenStream) -> $S::TokenStream;
-                fn is_empty($self: &$S::TokenStream) -> bool;
-                fn expand_expr($self: &$S::TokenStream) -> Result<$S::TokenStream, ()>;
-                fn from_str(src: &str) -> $S::TokenStream;
-                fn to_string($self: &$S::TokenStream) -> String;
-                fn from_token_tree(
-                    tree: TokenTree<$S::TokenStream, $S::Span, $S::Ident, $S::Literal>,
-                ) -> $S::TokenStream;
-                fn concat_trees(
-                    base: Option<$S::TokenStream>,
-                    trees: Vec<TokenTree<$S::TokenStream, $S::Span, $S::Ident, $S::Literal>>,
-                ) -> $S::TokenStream;
-                fn concat_streams(
-                    base: Option<$S::TokenStream>,
-                    streams: Vec<$S::TokenStream>,
-                ) -> $S::TokenStream;
-                fn into_trees(
-                    $self: $S::TokenStream
-                ) -> Vec<TokenTree<$S::TokenStream, $S::Span, $S::Ident, $S::Literal>>;
-            },
-            Ident {
-                fn new(string: &str, span: $S::Span, is_raw: bool) -> $S::Ident;
-                fn span($self: $S::Ident) -> $S::Span;
-                fn with_span($self: $S::Ident, span: $S::Span) -> $S::Ident;
-            },
-            Literal {
-                fn drop($self: $S::Literal);
-                fn clone($self: &$S::Literal) -> $S::Literal;
-                fn from_str(s: &str) -> Result<$S::Literal, ()>;
-                fn to_string($self: &$S::Literal) -> String;
-                fn debug_kind($self: &$S::Literal) -> String;
-                fn symbol($self: &$S::Literal) -> String;
-                fn suffix($self: &$S::Literal) -> Option<String>;
-                fn integer(n: &str) -> $S::Literal;
-                fn typed_integer(n: &str, kind: &str) -> $S::Literal;
-                fn float(n: &str) -> $S::Literal;
-                fn f32(n: &str) -> $S::Literal;
-                fn f64(n: &str) -> $S::Literal;
-                fn string(string: &str) -> $S::Literal;
-                fn character(ch: char) -> $S::Literal;
-                fn byte_string(bytes: &[u8]) -> $S::Literal;
-                fn span($self: &$S::Literal) -> $S::Span;
-                fn set_span($self: &mut $S::Literal, span: $S::Span);
-                fn subspan(
-                    $self: &$S::Literal,
-                    start: Bound<usize>,
-                    end: Bound<usize>,
-                ) -> Option<$S::Span>;
-            },
-            SourceFile {
-                fn drop($self: $S::SourceFile);
-                fn clone($self: &$S::SourceFile) -> $S::SourceFile;
-                fn eq($self: &$S::SourceFile, other: &$S::SourceFile) -> bool;
-                fn path($self: &$S::SourceFile) -> String;
-                fn is_real($self: &$S::SourceFile) -> bool;
-            },
-            MultiSpan {
-                fn drop($self: $S::MultiSpan);
-                fn new() -> $S::MultiSpan;
-                fn push($self: &mut $S::MultiSpan, span: $S::Span);
-            },
-            Diagnostic {
-                fn drop($self: $S::Diagnostic);
-                fn new(level: Level, msg: &str, span: $S::MultiSpan) -> $S::Diagnostic;
-                fn sub(
-                    $self: &mut $S::Diagnostic,
-                    level: Level,
-                    msg: &str,
-                    span: $S::MultiSpan,
-                );
-                fn emit($self: $S::Diagnostic);
-            },
-            Span {
-                fn debug($self: $S::Span) -> String;
-                fn source_file($self: $S::Span) -> $S::SourceFile;
-                fn parent($self: $S::Span) -> Option<$S::Span>;
-                fn source($self: $S::Span) -> $S::Span;
-                fn start($self: $S::Span) -> LineColumn;
-                fn end($self: $S::Span) -> LineColumn;
-                fn before($self: $S::Span) -> $S::Span;
-                fn after($self: $S::Span) -> $S::Span;
-                fn join($self: $S::Span, other: $S::Span) -> Option<$S::Span>;
-                fn resolved_at($self: $S::Span, at: $S::Span) -> $S::Span;
-                fn source_text($self: $S::Span) -> Option<String>;
-                fn save_span($self: $S::Span) -> usize;
-                fn recover_proc_macro_span(id: usize) -> $S::Span;
-            },
-        }
-    };
-}
-
-// FIXME(eddyb) this calls `encode` for each argument, but in reverse,
-// to match the ordering in `reverse_decode`.
-macro_rules! reverse_encode {
-    ($writer:ident;) => {};
-    ($writer:ident; $first:ident $(, $rest:ident)*) => {
-        reverse_encode!($writer; $($rest),*);
-        $first.encode(&mut $writer, &mut ());
-    }
-}
-
-// FIXME(eddyb) this calls `decode` for each argument, but in reverse,
-// to avoid borrow conflicts from borrows started by `&mut` arguments.
-macro_rules! reverse_decode {
-    ($reader:ident, $s:ident;) => {};
-    ($reader:ident, $s:ident; $first:ident: $first_ty:ty $(, $rest:ident: $rest_ty:ty)*) => {
-        reverse_decode!($reader, $s; $($rest: $rest_ty),*);
-        let $first = <$first_ty>::decode(&mut $reader, $s);
-    }
-}
-
-#[allow(unsafe_code)]
-mod buffer;
-#[forbid(unsafe_code)]
-pub mod client;
-#[allow(unsafe_code)]
-mod closure;
-#[forbid(unsafe_code)]
-mod handle;
-#[macro_use]
-#[forbid(unsafe_code)]
-mod rpc;
-#[allow(unsafe_code)]
-mod scoped_cell;
-#[allow(unsafe_code)]
-mod selfless_reify;
-#[forbid(unsafe_code)]
-pub mod server;
-
-use buffer::Buffer;
-pub use rpc::PanicMessage;
-use rpc::{Decode, DecodeMut, Encode, Reader, Writer};
-
-/// Configuration for establishing an active connection between a server and a
-/// client.  The server creates the bridge config (`run_server` in `server.rs`),
-/// then passes it to the client through the function pointer in the `run` field
-/// of `client::Client`. The client constructs a local `Bridge` from the config
-/// in TLS during its execution (`Bridge::{enter, with}` in `client.rs`).
-#[repr(C)]
-pub struct BridgeConfig<'a> {
-    /// Buffer used to pass initial input to the client.
-    input: Buffer,
-
-    /// Server-side function that the client uses to make requests.
-    dispatch: closure::Closure<'a, Buffer, Buffer>,
-
-    /// If 'true', always invoke the default panic hook
-    force_show_panics: bool,
-
-    // Prevent Send and Sync impls. `!Send`/`!Sync` is the usual way of doing
-    // this, but that requires unstable features. rust-analyzer uses this code
-    // and avoids unstable features.
-    _marker: marker::PhantomData<*mut ()>,
-}
-
-#[forbid(unsafe_code)]
-#[allow(non_camel_case_types)]
-mod api_tags {
-    use super::rpc::{DecodeMut, Encode, Reader, Writer};
-
-    macro_rules! declare_tags {
-        ($($name:ident {
-            $(fn $method:ident($($arg:ident: $arg_ty:ty),* $(,)?) $(-> $ret_ty:ty)*;)*
-        }),* $(,)?) => {
-            $(
-                pub(super) enum $name {
-                    $($method),*
-                }
-                rpc_encode_decode!(enum $name { $($method),* });
-            )*
-
-            pub(super) enum Method {
-                $($name($name)),*
-            }
-            rpc_encode_decode!(enum Method { $($name(m)),* });
-        }
-    }
-    with_api!(self, self, declare_tags);
-}
-
-/// Helper to wrap associated types to allow trait impl dispatch.
-/// That is, normally a pair of impls for `T::Foo` and `T::Bar`
-/// can overlap, but if the impls are, instead, on types like
-/// `Marked<T::Foo, Foo>` and `Marked<T::Bar, Bar>`, they can't.
-trait Mark {
-    type Unmarked;
-    fn mark(unmarked: Self::Unmarked) -> Self;
-}
-
-/// Unwrap types wrapped by `Mark::mark` (see `Mark` for details).
-trait Unmark {
-    type Unmarked;
-    fn unmark(self) -> Self::Unmarked;
-}
-
-#[derive(Copy, Clone, PartialEq, Eq, Hash)]
-struct Marked<T, M> {
-    value: T,
-    _marker: marker::PhantomData<M>,
-}
-
-impl<T, M> Mark for Marked<T, M> {
-    type Unmarked = T;
-    fn mark(unmarked: Self::Unmarked) -> Self {
-        Marked { value: unmarked, _marker: marker::PhantomData }
-    }
-}
-impl<T, M> Unmark for Marked<T, M> {
-    type Unmarked = T;
-    fn unmark(self) -> Self::Unmarked {
-        self.value
-    }
-}
-impl<'a, T, M> Unmark for &'a Marked<T, M> {
-    type Unmarked = &'a T;
-    fn unmark(self) -> Self::Unmarked {
-        &self.value
-    }
-}
-impl<'a, T, M> Unmark for &'a mut Marked<T, M> {
-    type Unmarked = &'a mut T;
-    fn unmark(self) -> Self::Unmarked {
-        &mut self.value
-    }
-}
-
-impl<T: Mark> Mark for Vec<T> {
-    type Unmarked = Vec<T::Unmarked>;
-    fn mark(unmarked: Self::Unmarked) -> Self {
-        // Should be a no-op due to std's in-place collect optimizations.
-        unmarked.into_iter().map(T::mark).collect()
-    }
-}
-impl<T: Unmark> Unmark for Vec<T> {
-    type Unmarked = Vec<T::Unmarked>;
-    fn unmark(self) -> Self::Unmarked {
-        // Should be a no-op due to std's in-place collect optimizations.
-        self.into_iter().map(T::unmark).collect()
-    }
-}
-
-macro_rules! mark_noop {
-    ($($ty:ty),* $(,)?) => {
-        $(
-            impl Mark for $ty {
-                type Unmarked = Self;
-                fn mark(unmarked: Self::Unmarked) -> Self {
-                    unmarked
-                }
-            }
-            impl Unmark for $ty {
-                type Unmarked = Self;
-                fn unmark(self) -> Self::Unmarked {
-                    self
-                }
-            }
-        )*
-    }
-}
-mark_noop! {
-    (),
-    bool,
-    char,
-    &'_ [u8],
-    &'_ str,
-    String,
-    u8,
-    usize,
-    Delimiter,
-    Level,
-    LineColumn,
-    Spacing,
-}
-
-rpc_encode_decode!(
-    enum Delimiter {
-        Parenthesis,
-        Brace,
-        Bracket,
-        None,
-    }
-);
-rpc_encode_decode!(
-    enum Level {
-        Error,
-        Warning,
-        Note,
-        Help,
-    }
-);
-rpc_encode_decode!(struct LineColumn { line, column });
-rpc_encode_decode!(
-    enum Spacing {
-        Alone,
-        Joint,
-    }
-);
-
-macro_rules! mark_compound {
-    (struct $name:ident <$($T:ident),+> { $($field:ident),* $(,)? }) => {
-        impl<$($T: Mark),+> Mark for $name <$($T),+> {
-            type Unmarked = $name <$($T::Unmarked),+>;
-            fn mark(unmarked: Self::Unmarked) -> Self {
-                $name {
-                    $($field: Mark::mark(unmarked.$field)),*
-                }
-            }
-        }
-        impl<$($T: Unmark),+> Unmark for $name <$($T),+> {
-            type Unmarked = $name <$($T::Unmarked),+>;
-            fn unmark(self) -> Self::Unmarked {
-                $name {
-                    $($field: Unmark::unmark(self.$field)),*
-                }
-            }
-        }
-    };
-    (enum $name:ident <$($T:ident),+> { $($variant:ident $(($field:ident))?),* $(,)? }) => {
-        impl<$($T: Mark),+> Mark for $name <$($T),+> {
-            type Unmarked = $name <$($T::Unmarked),+>;
-            fn mark(unmarked: Self::Unmarked) -> Self {
-                match unmarked {
-                    $($name::$variant $(($field))? => {
-                        $name::$variant $((Mark::mark($field)))?
-                    })*
-                }
-            }
-        }
-        impl<$($T: Unmark),+> Unmark for $name <$($T),+> {
-            type Unmarked = $name <$($T::Unmarked),+>;
-            fn unmark(self) -> Self::Unmarked {
-                match self {
-                    $($name::$variant $(($field))? => {
-                        $name::$variant $((Unmark::unmark($field)))?
-                    })*
-                }
-            }
-        }
-    }
-}
-
-macro_rules! compound_traits {
-    ($($t:tt)*) => {
-        rpc_encode_decode!($($t)*);
-        mark_compound!($($t)*);
-    };
-}
-
-compound_traits!(
-    enum Bound<T> {
-        Included(x),
-        Excluded(x),
-        Unbounded,
-    }
-);
-
-compound_traits!(
-    enum Option<T> {
-        Some(t),
-        None,
-    }
-);
-
-compound_traits!(
-    enum Result<T, E> {
-        Ok(t),
-        Err(e),
-    }
-);
-
-#[derive(Copy, Clone)]
-pub struct DelimSpan<Span> {
-    pub open: Span,
-    pub close: Span,
-    pub entire: Span,
-}
-
-impl<Span: Copy> DelimSpan<Span> {
-    pub fn from_single(span: Span) -> Self {
-        DelimSpan { open: span, close: span, entire: span }
-    }
-}
-
-compound_traits!(struct DelimSpan<Span> { open, close, entire });
-
-#[derive(Clone)]
-pub struct Group<TokenStream, Span> {
-    pub delimiter: Delimiter,
-    pub stream: Option<TokenStream>,
-    pub span: DelimSpan<Span>,
-}
-
-compound_traits!(struct Group<TokenStream, Span> { delimiter, stream, span });
-
-#[derive(Clone)]
-pub struct Punct<Span> {
-    pub ch: u8,
-    pub joint: bool,
-    pub span: Span,
-}
-
-compound_traits!(struct Punct<Span> { ch, joint, span });
-
-#[derive(Clone)]
-pub enum TokenTree<TokenStream, Span, Ident, Literal> {
-    Group(Group<TokenStream, Span>),
-    Punct(Punct<Span>),
-    Ident(Ident),
-    Literal(Literal),
-}
-
-compound_traits!(
-    enum TokenTree<TokenStream, Span, Ident, Literal> {
-        Group(tt),
-        Punct(tt),
-        Ident(tt),
-        Literal(tt),
-    }
-);
-
-/// Globals provided alongside the initial inputs for a macro expansion.
-/// Provides values such as spans which are used frequently to avoid RPC.
-#[derive(Clone)]
-pub struct ExpnGlobals<Span> {
-    pub def_site: Span,
-    pub call_site: Span,
-    pub mixed_site: Span,
-}
-
-compound_traits!(
-    struct ExpnGlobals<Span> { def_site, call_site, mixed_site }
-);

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/rpc.rs

@@ -1,304 +0,0 @@
-//! Serialization for client-server communication.
-
-use std::any::Any;
-use std::char;
-use std::io::Write;
-use std::num::NonZeroU32;
-use std::str;
-
-pub(super) type Writer = super::buffer::Buffer;
-
-pub(super) trait Encode<S>: Sized {
-    fn encode(self, w: &mut Writer, s: &mut S);
-}
-
-pub(super) type Reader<'a> = &'a [u8];
-
-pub(super) trait Decode<'a, 's, S>: Sized {
-    fn decode(r: &mut Reader<'a>, s: &'s S) -> Self;
-}
-
-pub(super) trait DecodeMut<'a, 's, S>: Sized {
-    fn decode(r: &mut Reader<'a>, s: &'s mut S) -> Self;
-}
-
-macro_rules! rpc_encode_decode {
-    (le $ty:ty) => {
-        impl<S> Encode<S> for $ty {
-            fn encode(self, w: &mut Writer, _: &mut S) {
-                w.extend_from_array(&self.to_le_bytes());
-            }
-        }
-
-        impl<S> DecodeMut<'_, '_, S> for $ty {
-            fn decode(r: &mut Reader<'_>, _: &mut S) -> Self {
-                const N: usize = ::std::mem::size_of::<$ty>();
-
-                let mut bytes = [0; N];
-                bytes.copy_from_slice(&r[..N]);
-                *r = &r[N..];
-
-                Self::from_le_bytes(bytes)
-            }
-        }
-    };
-    (struct $name:ident $(<$($T:ident),+>)? { $($field:ident),* $(,)? }) => {
-        impl<S, $($($T: Encode<S>),+)?> Encode<S> for $name $(<$($T),+>)? {
-            fn encode(self, w: &mut Writer, s: &mut S) {
-                $(self.$field.encode(w, s);)*
-            }
-        }
-
-        impl<'a, S, $($($T: for<'s> DecodeMut<'a, 's, S>),+)?> DecodeMut<'a, '_, S>
-            for $name $(<$($T),+>)?
-        {
-            fn decode(r: &mut Reader<'a>, s: &mut S) -> Self {
-                $name {
-                    $($field: DecodeMut::decode(r, s)),*
-                }
-            }
-        }
-    };
-    (enum $name:ident $(<$($T:ident),+>)? { $($variant:ident $(($field:ident))*),* $(,)? }) => {
-        impl<S, $($($T: Encode<S>),+)?> Encode<S> for $name $(<$($T),+>)? {
-            fn encode(self, w: &mut Writer, s: &mut S) {
-                // HACK(eddyb): `Tag` enum duplicated between the
-                // two impls as there's no other place to stash it.
-                #[allow(non_upper_case_globals)]
-                mod tag {
-                    #[repr(u8)] enum Tag { $($variant),* }
-
-                    $(pub const $variant: u8 = Tag::$variant as u8;)*
-                }
-
-                match self {
-                    $($name::$variant $(($field))* => {
-                        tag::$variant.encode(w, s);
-                        $($field.encode(w, s);)*
-                    })*
-                }
-            }
-        }
-
-        impl<'a, S, $($($T: for<'s> DecodeMut<'a, 's, S>),+)?> DecodeMut<'a, '_, S>
-            for $name $(<$($T),+>)?
-        {
-            fn decode(r: &mut Reader<'a>, s: &mut S) -> Self {
-                // HACK(eddyb): `Tag` enum duplicated between the
-                // two impls as there's no other place to stash it.
-                #[allow(non_upper_case_globals)]
-                mod tag {
-                    #[repr(u8)] enum Tag { $($variant),* }
-
-                    $(pub const $variant: u8 = Tag::$variant as u8;)*
-                }
-
-                match u8::decode(r, s) {
-                    $(tag::$variant => {
-                        $(let $field = DecodeMut::decode(r, s);)*
-                        $name::$variant $(($field))*
-                    })*
-                    _ => unreachable!(),
-                }
-            }
-        }
-    }
-}
-
-impl<S> Encode<S> for () {
-    fn encode(self, _: &mut Writer, _: &mut S) {}
-}
-
-impl<S> DecodeMut<'_, '_, S> for () {
-    fn decode(_: &mut Reader<'_>, _: &mut S) -> Self {}
-}
-
-impl<S> Encode<S> for u8 {
-    fn encode(self, w: &mut Writer, _: &mut S) {
-        w.push(self);
-    }
-}
-
-impl<S> DecodeMut<'_, '_, S> for u8 {
-    fn decode(r: &mut Reader<'_>, _: &mut S) -> Self {
-        let x = r[0];
-        *r = &r[1..];
-        x
-    }
-}
-
-rpc_encode_decode!(le u32);
-rpc_encode_decode!(le usize);
-
-impl<S> Encode<S> for bool {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        (self as u8).encode(w, s);
-    }
-}
-
-impl<S> DecodeMut<'_, '_, S> for bool {
-    fn decode(r: &mut Reader<'_>, s: &mut S) -> Self {
-        match u8::decode(r, s) {
-            0 => false,
-            1 => true,
-            _ => unreachable!(),
-        }
-    }
-}
-
-impl<S> Encode<S> for char {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        (self as u32).encode(w, s);
-    }
-}
-
-impl<S> DecodeMut<'_, '_, S> for char {
-    fn decode(r: &mut Reader<'_>, s: &mut S) -> Self {
-        char::from_u32(u32::decode(r, s)).unwrap()
-    }
-}
-
-impl<S> Encode<S> for NonZeroU32 {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        self.get().encode(w, s);
-    }
-}
-
-impl<S> DecodeMut<'_, '_, S> for NonZeroU32 {
-    fn decode(r: &mut Reader<'_>, s: &mut S) -> Self {
-        Self::new(u32::decode(r, s)).unwrap()
-    }
-}
-
-impl<S, A: Encode<S>, B: Encode<S>> Encode<S> for (A, B) {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        self.0.encode(w, s);
-        self.1.encode(w, s);
-    }
-}
-
-impl<'a, S, A: for<'s> DecodeMut<'a, 's, S>, B: for<'s> DecodeMut<'a, 's, S>> DecodeMut<'a, '_, S>
-    for (A, B)
-{
-    fn decode(r: &mut Reader<'a>, s: &mut S) -> Self {
-        (DecodeMut::decode(r, s), DecodeMut::decode(r, s))
-    }
-}
-
-impl<S> Encode<S> for &[u8] {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        self.len().encode(w, s);
-        w.write_all(self).unwrap();
-    }
-}
-
-impl<'a, S> DecodeMut<'a, '_, S> for &'a [u8] {
-    fn decode(r: &mut Reader<'a>, s: &mut S) -> Self {
-        let len = usize::decode(r, s);
-        let xs = &r[..len];
-        *r = &r[len..];
-        xs
-    }
-}
-
-impl<S> Encode<S> for &str {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        self.as_bytes().encode(w, s);
-    }
-}
-
-impl<'a, S> DecodeMut<'a, '_, S> for &'a str {
-    fn decode(r: &mut Reader<'a>, s: &mut S) -> Self {
-        str::from_utf8(<&[u8]>::decode(r, s)).unwrap()
-    }
-}
-
-impl<S> Encode<S> for String {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        self[..].encode(w, s);
-    }
-}
-
-impl<S> DecodeMut<'_, '_, S> for String {
-    fn decode(r: &mut Reader<'_>, s: &mut S) -> Self {
-        <&str>::decode(r, s).to_string()
-    }
-}
-
-impl<S, T: Encode<S>> Encode<S> for Vec<T> {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        self.len().encode(w, s);
-        for x in self {
-            x.encode(w, s);
-        }
-    }
-}
-
-impl<'a, S, T: for<'s> DecodeMut<'a, 's, S>> DecodeMut<'a, '_, S> for Vec<T> {
-    fn decode(r: &mut Reader<'a>, s: &mut S) -> Self {
-        let len = usize::decode(r, s);
-        let mut vec = Vec::with_capacity(len);
-        for _ in 0..len {
-            vec.push(T::decode(r, s));
-        }
-        vec
-    }
-}
-
-/// Simplified version of panic payloads, ignoring
-/// types other than `&'static str` and `String`.
-pub enum PanicMessage {
-    StaticStr(&'static str),
-    String(String),
-    Unknown,
-}
-
-impl From<Box<dyn Any + Send>> for PanicMessage {
-    fn from(payload: Box<dyn Any + Send + 'static>) -> Self {
-        if let Some(s) = payload.downcast_ref::<&'static str>() {
-            return PanicMessage::StaticStr(s);
-        }
-        if let Ok(s) = payload.downcast::<String>() {
-            return PanicMessage::String(*s);
-        }
-        PanicMessage::Unknown
-    }
-}
-
-impl Into<Box<dyn Any + Send>> for PanicMessage {
-    fn into(self) -> Box<dyn Any + Send> {
-        match self {
-            PanicMessage::StaticStr(s) => Box::new(s),
-            PanicMessage::String(s) => Box::new(s),
-            PanicMessage::Unknown => {
-                struct UnknownPanicMessage;
-                Box::new(UnknownPanicMessage)
-            }
-        }
-    }
-}
-
-impl PanicMessage {
-    pub fn as_str(&self) -> Option<&str> {
-        match self {
-            PanicMessage::StaticStr(s) => Some(s),
-            PanicMessage::String(s) => Some(s),
-            PanicMessage::Unknown => None,
-        }
-    }
-}
-
-impl<S> Encode<S> for PanicMessage {
-    fn encode(self, w: &mut Writer, s: &mut S) {
-        self.as_str().encode(w, s);
-    }
-}
-
-impl<S> DecodeMut<'_, '_, S> for PanicMessage {
-    fn decode(r: &mut Reader<'_>, s: &mut S) -> Self {
-        match Option::<String>::decode(r, s) {
-            Some(s) => PanicMessage::String(s),
-            None => PanicMessage::Unknown,
-        }
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/scoped_cell.rs

@@ -1,81 +0,0 @@
-//! `Cell` variant for (scoped) existential lifetimes.
-
-use std::cell::Cell;
-use std::mem;
-use std::ops::{Deref, DerefMut};
-
-/// Type lambda application, with a lifetime.
-#[allow(unused_lifetimes)]
-pub trait ApplyL<'a> {
-    type Out;
-}
-
-/// Type lambda taking a lifetime, i.e., `Lifetime -> Type`.
-pub trait LambdaL: for<'a> ApplyL<'a> {}
-
-impl<T: for<'a> ApplyL<'a>> LambdaL for T {}
-
-// HACK(eddyb) work around projection limitations with a newtype
-// FIXME(#52812) replace with `&'a mut <T as ApplyL<'b>>::Out`
-pub struct RefMutL<'a, 'b, T: LambdaL>(&'a mut <T as ApplyL<'b>>::Out);
-
-impl<'a, 'b, T: LambdaL> Deref for RefMutL<'a, 'b, T> {
-    type Target = <T as ApplyL<'b>>::Out;
-    fn deref(&self) -> &Self::Target {
-        self.0
-    }
-}
-
-impl<'a, 'b, T: LambdaL> DerefMut for RefMutL<'a, 'b, T> {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        self.0
-    }
-}
-
-pub struct ScopedCell<T: LambdaL>(Cell<<T as ApplyL<'static>>::Out>);
-
-impl<T: LambdaL> ScopedCell<T> {
-    pub const fn new(value: <T as ApplyL<'static>>::Out) -> Self {
-        ScopedCell(Cell::new(value))
-    }
-
-    /// Sets the value in `self` to `replacement` while
-    /// running `f`, which gets the old value, mutably.
-    /// The old value will be restored after `f` exits, even
-    /// by panic, including modifications made to it by `f`.
-    pub fn replace<'a, R>(
-        &self,
-        replacement: <T as ApplyL<'a>>::Out,
-        f: impl for<'b, 'c> FnOnce(RefMutL<'b, 'c, T>) -> R,
-    ) -> R {
-        /// Wrapper that ensures that the cell always gets filled
-        /// (with the original state, optionally changed by `f`),
-        /// even if `f` had panicked.
-        struct PutBackOnDrop<'a, T: LambdaL> {
-            cell: &'a ScopedCell<T>,
-            value: Option<<T as ApplyL<'static>>::Out>,
-        }
-
-        impl<'a, T: LambdaL> Drop for PutBackOnDrop<'a, T> {
-            fn drop(&mut self) {
-                self.cell.0.set(self.value.take().unwrap());
-            }
-        }
-
-        let mut put_back_on_drop = PutBackOnDrop {
-            cell: self,
-            value: Some(self.0.replace(unsafe {
-                let erased = mem::transmute_copy(&replacement);
-                mem::forget(replacement);
-                erased
-            })),
-        };
-
-        f(RefMutL(put_back_on_drop.value.as_mut().unwrap()))
-    }
-
-    /// Sets the value in `self` to `value` while running `f`.
-    pub fn set<R>(&self, value: <T as ApplyL<'_>>::Out, f: impl FnOnce() -> R) -> R {
-        self.replace(value, |_| f())
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/selfless_reify.rs

@@ -1,84 +0,0 @@
-//! Abstraction for creating `fn` pointers from any callable that *effectively*
-//! has the equivalent of implementing `Default`, even if the compiler neither
-//! provides `Default` nor allows reifying closures (i.e. creating `fn` pointers)
-//! other than those with absolutely no captures.
-//!
-//! More specifically, for a closure-like type to be "effectively `Default`":
-//! * it must be a ZST (zero-sized type): no information contained within, so
-//!   that `Default`'s return value (if it were implemented) is unambiguous
-//! * it must be `Copy`: no captured "unique ZST tokens" or any other similar
-//!   types that would make duplicating values at will unsound
-//!   * combined with the ZST requirement, this confers a kind of "telecopy"
-//!     ability: similar to `Copy`, but without keeping the value around, and
-//!     instead "reconstructing" it (a noop given it's a ZST) when needed
-//! * it must be *provably* inhabited: no captured uninhabited types or any
-//!   other types that cannot be constructed by the user of this abstraction
-//!   * the proof is a value of the closure-like type itself, in a sense the
-//!     "seed" for the "telecopy" process made possible by ZST + `Copy`
-//!   * this requirement is the only reason an abstraction limited to a specific
-//!     usecase is required: ZST + `Copy` can be checked with *at worst* a panic
-//!     at the "attempted `::default()` call" time, but that doesn't guarantee
-//!     that the value can be soundly created, and attempting to use the typical
-//!     "proof ZST token" approach leads yet again to having a ZST + `Copy` type
-//!     that is not proof of anything without a value (i.e. isomorphic to a
-//!     newtype of the type it's trying to prove the inhabitation of)
-//!
-//! A more flexible (and safer) solution to the general problem could exist once
-//! `const`-generic parameters can have type parameters in their types:
-//!
-//! ```rust,ignore (needs future const-generics)
-//! extern "C" fn ffi_wrapper<
-//!     A, R,
-//!     F: Fn(A) -> R,
-//!     const f: F, // <-- this `const`-generic is not yet allowed
-//! >(arg: A) -> R {
-//!     f(arg)
-//! }
-//! ```
-
-use std::mem;
-
-// FIXME(eddyb) this could be `trait` impls except for the `const fn` requirement.
-macro_rules! define_reify_functions {
-    ($(
-        fn $name:ident $(<$($param:ident),*>)?
-            for $(extern $abi:tt)? fn($($arg:ident: $arg_ty:ty),*) -> $ret_ty:ty;
-    )+) => {
-        $(pub const fn $name<
-            $($($param,)*)?
-            F: Fn($($arg_ty),*) -> $ret_ty + Copy
-        >(f: F) -> $(extern $abi)? fn($($arg_ty),*) -> $ret_ty {
-            // FIXME(eddyb) describe the `F` type (e.g. via `type_name::<F>`) once panic
-            // formatting becomes possible in `const fn`.
-            assert!(mem::size_of::<F>() == 0, "selfless_reify: closure must be zero-sized");
-
-            $(extern $abi)? fn wrapper<
-                $($($param,)*)?
-                F: Fn($($arg_ty),*) -> $ret_ty + Copy
-            >($($arg: $arg_ty),*) -> $ret_ty {
-                let f = unsafe {
-                    // SAFETY: `F` satisfies all criteria for "out of thin air"
-                    // reconstructability (see module-level doc comment).
-                    mem::MaybeUninit::<F>::uninit().assume_init()
-                };
-                f($($arg),*)
-            }
-            let _f_proof = f;
-            wrapper::<
-                $($($param,)*)?
-                F
-            >
-        })+
-    }
-}
-
-define_reify_functions! {
-    fn _reify_to_extern_c_fn_unary<A, R> for extern "C" fn(arg: A) -> R;
-
-    // HACK(eddyb) this abstraction is used with `for<'a> fn(BridgeConfig<'a>)
-    // -> T` but that doesn't work with just `reify_to_extern_c_fn_unary`
-    // because of the `fn` pointer type being "higher-ranked" (i.e. the
-    // `for<'a>` binder).
-    // FIXME(eddyb) try to remove the lifetime from `BridgeConfig`, that'd help.
-    fn reify_to_extern_c_fn_hrt_bridge<R> for extern "C" fn(bridge: super::BridgeConfig<'_>) -> R;
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/server.rs

@@ -1,339 +0,0 @@
-//! Server-side traits.
-
-use super::*;
-
-// FIXME(eddyb) generate the definition of `HandleStore` in `server.rs`.
-use super::client::HandleStore;
-
-pub trait Types {
-    type FreeFunctions: 'static;
-    type TokenStream: 'static + Clone;
-    type Ident: 'static + Copy + Eq + Hash;
-    type Literal: 'static + Clone;
-    type SourceFile: 'static + Clone;
-    type MultiSpan: 'static;
-    type Diagnostic: 'static;
-    type Span: 'static + Copy + Eq + Hash;
-}
-
-/// Declare an associated fn of one of the traits below, adding necessary
-/// default bodies.
-macro_rules! associated_fn {
-    (fn drop(&mut self, $arg:ident: $arg_ty:ty)) =>
-        (fn drop(&mut self, $arg: $arg_ty) { mem::drop($arg) });
-
-    (fn clone(&mut self, $arg:ident: $arg_ty:ty) -> $ret_ty:ty) =>
-        (fn clone(&mut self, $arg: $arg_ty) -> $ret_ty { $arg.clone() });
-
-    ($($item:tt)*) => ($($item)*;)
-}
-
-macro_rules! declare_server_traits {
-    ($($name:ident {
-        $(fn $method:ident($($arg:ident: $arg_ty:ty),* $(,)?) $(-> $ret_ty:ty)?;)*
-    }),* $(,)?) => {
-        $(pub trait $name: Types {
-            $(associated_fn!(fn $method(&mut self, $($arg: $arg_ty),*) $(-> $ret_ty)?);)*
-        })*
-
-        pub trait Server: Types $(+ $name)* {
-            fn globals(&mut self) -> ExpnGlobals<Self::Span>;
-        }
-    }
-}
-with_api!(Self, self_, declare_server_traits);
-
-pub(super) struct MarkedTypes<S: Types>(S);
-
-impl<S: Server> Server for MarkedTypes<S> {
-    fn globals(&mut self) -> ExpnGlobals<Self::Span> {
-        <_>::mark(Server::globals(&mut self.0))
-    }
-}
-
-macro_rules! define_mark_types_impls {
-    ($($name:ident {
-        $(fn $method:ident($($arg:ident: $arg_ty:ty),* $(,)?) $(-> $ret_ty:ty)?;)*
-    }),* $(,)?) => {
-        impl<S: Types> Types for MarkedTypes<S> {
-            $(type $name = Marked<S::$name, client::$name>;)*
-        }
-
-        $(impl<S: $name> $name for MarkedTypes<S> {
-            $(fn $method(&mut self, $($arg: $arg_ty),*) $(-> $ret_ty)? {
-                <_>::mark($name::$method(&mut self.0, $($arg.unmark()),*))
-            })*
-        })*
-    }
-}
-with_api!(Self, self_, define_mark_types_impls);
-
-struct Dispatcher<S: Types> {
-    handle_store: HandleStore<S>,
-    server: S,
-}
-
-macro_rules! define_dispatcher_impl {
-    ($($name:ident {
-        $(fn $method:ident($($arg:ident: $arg_ty:ty),* $(,)?) $(-> $ret_ty:ty)?;)*
-    }),* $(,)?) => {
-        // FIXME(eddyb) `pub` only for `ExecutionStrategy` below.
-        pub trait DispatcherTrait {
-            // HACK(eddyb) these are here to allow `Self::$name` to work below.
-            $(type $name;)*
-            fn dispatch(&mut self, buf: Buffer) -> Buffer;
-        }
-
-        impl<S: Server> DispatcherTrait for Dispatcher<MarkedTypes<S>> {
-            $(type $name = <MarkedTypes<S> as Types>::$name;)*
-            fn dispatch(&mut self, mut buf: Buffer) -> Buffer {
-                let Dispatcher { handle_store, server } = self;
-
-                let mut reader = &buf[..];
-                match api_tags::Method::decode(&mut reader, &mut ()) {
-                    $(api_tags::Method::$name(m) => match m {
-                        $(api_tags::$name::$method => {
-                            let mut call_method = || {
-                                reverse_decode!(reader, handle_store; $($arg: $arg_ty),*);
-                                $name::$method(server, $($arg),*)
-                            };
-                            // HACK(eddyb) don't use `panic::catch_unwind` in a panic.
-                            // If client and server happen to use the same `libstd`,
-                            // `catch_unwind` asserts that the panic counter was 0,
-                            // even when the closure passed to it didn't panic.
-                            let r = if thread::panicking() {
-                                Ok(call_method())
-                            } else {
-                                panic::catch_unwind(panic::AssertUnwindSafe(call_method))
-                                    .map_err(PanicMessage::from)
-                            };
-
-                            buf.clear();
-                            r.encode(&mut buf, handle_store);
-                        })*
-                    }),*
-                }
-                buf
-            }
-        }
-    }
-}
-with_api!(Self, self_, define_dispatcher_impl);
-
-pub trait ExecutionStrategy {
-    fn run_bridge_and_client(
-        &self,
-        dispatcher: &mut impl DispatcherTrait,
-        input: Buffer,
-        run_client: extern "C" fn(BridgeConfig<'_>) -> Buffer,
-        force_show_panics: bool,
-    ) -> Buffer;
-}
-
-pub struct SameThread;
-
-impl ExecutionStrategy for SameThread {
-    fn run_bridge_and_client(
-        &self,
-        dispatcher: &mut impl DispatcherTrait,
-        input: Buffer,
-        run_client: extern "C" fn(BridgeConfig<'_>) -> Buffer,
-        force_show_panics: bool,
-    ) -> Buffer {
-        let mut dispatch = |buf| dispatcher.dispatch(buf);
-
-        run_client(BridgeConfig {
-            input,
-            dispatch: (&mut dispatch).into(),
-            force_show_panics,
-            _marker: marker::PhantomData,
-        })
-    }
-}
-
-// NOTE(eddyb) Two implementations are provided, the second one is a bit
-// faster but neither is anywhere near as fast as same-thread execution.
-
-pub struct CrossThread1;
-
-impl ExecutionStrategy for CrossThread1 {
-    fn run_bridge_and_client(
-        &self,
-        dispatcher: &mut impl DispatcherTrait,
-        input: Buffer,
-        run_client: extern "C" fn(BridgeConfig<'_>) -> Buffer,
-        force_show_panics: bool,
-    ) -> Buffer {
-        use std::sync::mpsc::channel;
-
-        let (req_tx, req_rx) = channel();
-        let (res_tx, res_rx) = channel();
-
-        let join_handle = thread::spawn(move || {
-            let mut dispatch = |buf| {
-                req_tx.send(buf).unwrap();
-                res_rx.recv().unwrap()
-            };
-
-            run_client(BridgeConfig {
-                input,
-                dispatch: (&mut dispatch).into(),
-                force_show_panics,
-                _marker: marker::PhantomData,
-            })
-        });
-
-        for b in req_rx {
-            res_tx.send(dispatcher.dispatch(b)).unwrap();
-        }
-
-        join_handle.join().unwrap()
-    }
-}
-
-pub struct CrossThread2;
-
-impl ExecutionStrategy for CrossThread2 {
-    fn run_bridge_and_client(
-        &self,
-        dispatcher: &mut impl DispatcherTrait,
-        input: Buffer,
-        run_client: extern "C" fn(BridgeConfig<'_>) -> Buffer,
-        force_show_panics: bool,
-    ) -> Buffer {
-        use std::sync::{Arc, Mutex};
-
-        enum State<T> {
-            Req(T),
-            Res(T),
-        }
-
-        let mut state = Arc::new(Mutex::new(State::Res(Buffer::new())));
-
-        let server_thread = thread::current();
-        let state2 = state.clone();
-        let join_handle = thread::spawn(move || {
-            let mut dispatch = |b| {
-                *state2.lock().unwrap() = State::Req(b);
-                server_thread.unpark();
-                loop {
-                    thread::park();
-                    if let State::Res(b) = &mut *state2.lock().unwrap() {
-                        break b.take();
-                    }
-                }
-            };
-
-            let r = run_client(BridgeConfig {
-                input,
-                dispatch: (&mut dispatch).into(),
-                force_show_panics,
-                _marker: marker::PhantomData,
-            });
-
-            // Wake up the server so it can exit the dispatch loop.
-            drop(state2);
-            server_thread.unpark();
-
-            r
-        });
-
-        // Check whether `state2` was dropped, to know when to stop.
-        while Arc::get_mut(&mut state).is_none() {
-            thread::park();
-            let mut b = match &mut *state.lock().unwrap() {
-                State::Req(b) => b.take(),
-                _ => continue,
-            };
-            b = dispatcher.dispatch(b.take());
-            *state.lock().unwrap() = State::Res(b);
-            join_handle.thread().unpark();
-        }
-
-        join_handle.join().unwrap()
-    }
-}
-
-fn run_server<
-    S: Server,
-    I: Encode<HandleStore<MarkedTypes<S>>>,
-    O: for<'a, 's> DecodeMut<'a, 's, HandleStore<MarkedTypes<S>>>,
->(
-    strategy: &impl ExecutionStrategy,
-    handle_counters: &'static client::HandleCounters,
-    server: S,
-    input: I,
-    run_client: extern "C" fn(BridgeConfig<'_>) -> Buffer,
-    force_show_panics: bool,
-) -> Result<O, PanicMessage> {
-    let mut dispatcher =
-        Dispatcher { handle_store: HandleStore::new(handle_counters), server: MarkedTypes(server) };
-
-    let globals = dispatcher.server.globals();
-
-    let mut buf = Buffer::new();
-    (globals, input).encode(&mut buf, &mut dispatcher.handle_store);
-
-    buf = strategy.run_bridge_and_client(&mut dispatcher, buf, run_client, force_show_panics);
-
-    Result::decode(&mut &buf[..], &mut dispatcher.handle_store)
-}
-
-impl client::Client<super::super::TokenStream, super::super::TokenStream> {
-    pub fn run<S>(
-        &self,
-        strategy: &impl ExecutionStrategy,
-        server: S,
-        input: S::TokenStream,
-        force_show_panics: bool,
-    ) -> Result<S::TokenStream, PanicMessage>
-    where
-        S: Server,
-        S::TokenStream: Default,
-    {
-        let client::Client { get_handle_counters, run, _marker } = *self;
-        run_server(
-            strategy,
-            get_handle_counters(),
-            server,
-            <MarkedTypes<S> as Types>::TokenStream::mark(input),
-            run,
-            force_show_panics,
-        )
-        .map(|s| <Option<<MarkedTypes<S> as Types>::TokenStream>>::unmark(s).unwrap_or_default())
-    }
-}
-
-impl
-    client::Client<
-        (super::super::TokenStream, super::super::TokenStream),
-        super::super::TokenStream,
-    >
-{
-    pub fn run<S>(
-        &self,
-        strategy: &impl ExecutionStrategy,
-        server: S,
-        input: S::TokenStream,
-        input2: S::TokenStream,
-        force_show_panics: bool,
-    ) -> Result<S::TokenStream, PanicMessage>
-    where
-        S: Server,
-        S::TokenStream: Default,
-    {
-        let client::Client { get_handle_counters, run, _marker } = *self;
-        run_server(
-            strategy,
-            get_handle_counters(),
-            server,
-            (
-                <MarkedTypes<S> as Types>::TokenStream::mark(input),
-                <MarkedTypes<S> as Types>::TokenStream::mark(input2),
-            ),
-            run,
-            force_show_panics,
-        )
-        .map(|s| <Option<<MarkedTypes<S> as Types>::TokenStream>>::unmark(s).unwrap_or_default())
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/diagnostic.rs

@@ -1,166 +0,0 @@
-//! lib-proc-macro diagnostic
-//!
-//! Copy from <https://github.com/rust-lang/rust/blob/e45d9973b2665897a768312e971b82cc62633103/src/libproc_macro/diagnostic.rs>
-//! augmented with removing unstable features
-
-use super::Span;
-
-/// An enum representing a diagnostic level.
-#[derive(Copy, Clone, Debug)]
-#[non_exhaustive]
-pub enum Level {
-    /// An error.
-    Error,
-    /// A warning.
-    Warning,
-    /// A note.
-    Note,
-    /// A help message.
-    Help,
-}
-
-/// Trait implemented by types that can be converted into a set of `Span`s.
-pub trait MultiSpan {
-    /// Converts `self` into a `Vec<Span>`.
-    fn into_spans(self) -> Vec<Span>;
-}
-
-impl MultiSpan for Span {
-    fn into_spans(self) -> Vec<Span> {
-        vec![self]
-    }
-}
-
-impl MultiSpan for Vec<Span> {
-    fn into_spans(self) -> Vec<Span> {
-        self
-    }
-}
-
-impl<'a> MultiSpan for &'a [Span] {
-    fn into_spans(self) -> Vec<Span> {
-        self.to_vec()
-    }
-}
-
-/// A structure representing a diagnostic message and associated children
-/// messages.
-#[derive(Clone, Debug)]
-pub struct Diagnostic {
-    level: Level,
-    message: String,
-    spans: Vec<Span>,
-    children: Vec<Diagnostic>,
-}
-
-macro_rules! diagnostic_child_methods {
-    ($spanned:ident, $regular:ident, $level:expr) => {
-        #[doc = concat!("Adds a new child diagnostics message to `self` with the [`",
-                        stringify!($level), "`] level, and the given `spans` and `message`.")]
-        pub fn $spanned<S, T>(mut self, spans: S, message: T) -> Diagnostic
-        where
-            S: MultiSpan,
-            T: Into<String>,
-        {
-            self.children.push(Diagnostic::spanned(spans, $level, message));
-            self
-        }
-
-        #[doc = concat!("Adds a new child diagnostic message to `self` with the [`",
-                        stringify!($level), "`] level, and the given `message`.")]
-        pub fn $regular<T: Into<String>>(mut self, message: T) -> Diagnostic {
-            self.children.push(Diagnostic::new($level, message));
-            self
-        }
-    };
-}
-
-/// Iterator over the children diagnostics of a `Diagnostic`.
-#[derive(Debug, Clone)]
-pub struct Children<'a>(std::slice::Iter<'a, Diagnostic>);
-
-impl<'a> Iterator for Children<'a> {
-    type Item = &'a Diagnostic;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        self.0.next()
-    }
-}
-
-impl Diagnostic {
-    /// Creates a new diagnostic with the given `level` and `message`.
-    pub fn new<T: Into<String>>(level: Level, message: T) -> Diagnostic {
-        Diagnostic { level, message: message.into(), spans: vec![], children: vec![] }
-    }
-
-    /// Creates a new diagnostic with the given `level` and `message` pointing to
-    /// the given set of `spans`.
-    pub fn spanned<S, T>(spans: S, level: Level, message: T) -> Diagnostic
-    where
-        S: MultiSpan,
-        T: Into<String>,
-    {
-        Diagnostic { level, message: message.into(), spans: spans.into_spans(), children: vec![] }
-    }
-
-    diagnostic_child_methods!(span_error, error, Level::Error);
-    diagnostic_child_methods!(span_warning, warning, Level::Warning);
-    diagnostic_child_methods!(span_note, note, Level::Note);
-    diagnostic_child_methods!(span_help, help, Level::Help);
-
-    /// Returns the diagnostic `level` for `self`.
-    pub fn level(&self) -> Level {
-        self.level
-    }
-
-    /// Sets the level in `self` to `level`.
-    pub fn set_level(&mut self, level: Level) {
-        self.level = level;
-    }
-
-    /// Returns the message in `self`.
-    pub fn message(&self) -> &str {
-        &self.message
-    }
-
-    /// Sets the message in `self` to `message`.
-    pub fn set_message<T: Into<String>>(&mut self, message: T) {
-        self.message = message.into();
-    }
-
-    /// Returns the `Span`s in `self`.
-    pub fn spans(&self) -> &[Span] {
-        &self.spans
-    }
-
-    /// Sets the `Span`s in `self` to `spans`.
-    pub fn set_spans<S: MultiSpan>(&mut self, spans: S) {
-        self.spans = spans.into_spans();
-    }
-
-    /// Returns an iterator over the children diagnostics of `self`.
-    pub fn children(&self) -> Children<'_> {
-        Children(self.children.iter())
-    }
-
-    /// Emit the diagnostic.
-    pub fn emit(self) {
-        fn to_internal(spans: Vec<Span>) -> super::bridge::client::MultiSpan {
-            let mut multi_span = super::bridge::client::MultiSpan::new();
-            for span in spans {
-                multi_span.push(span.0);
-            }
-            multi_span
-        }
-
-        let mut diag = super::bridge::client::Diagnostic::new(
-            self.level,
-            &self.message[..],
-            to_internal(self.spans),
-        );
-        for c in self.children {
-            diag.sub(c.level, &c.message[..], to_internal(c.spans));
-        }
-        diag.emit();
-    }
-}

crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/quote.rs

@@ -1,139 +0,0 @@
-//! # Quasiquoter
-//! This file contains the implementation internals of the quasiquoter provided by `quote!`.
-
-//! This quasiquoter uses macros 2.0 hygiene to reliably access
-//! items from `proc_macro`, to build a `proc_macro::TokenStream`.
-
-use super::{Delimiter, Group, Ident, Literal, Punct, Spacing, Span, TokenStream, TokenTree};
-
-macro_rules! quote_tt {
-    (($($t:tt)*)) => { Group::new(Delimiter::Parenthesis, quote!($($t)*)) };
-    ([$($t:tt)*]) => { Group::new(Delimiter::Bracket, quote!($($t)*)) };
-    ({$($t:tt)*}) => { Group::new(Delimiter::Brace, quote!($($t)*)) };
-    (,) => { Punct::new(',', Spacing::Alone) };
-    (.) => { Punct::new('.', Spacing::Alone) };
-    (;) => { Punct::new(';', Spacing::Alone) };
-    (!) => { Punct::new('!', Spacing::Alone) };
-    (<) => { Punct::new('<', Spacing::Alone) };
-    (>) => { Punct::new('>', Spacing::Alone) };
-    (&) => { Punct::new('&', Spacing::Alone) };
-    (=) => { Punct::new('=', Spacing::Alone) };
-    ($i:ident) => { Ident::new(stringify!($i), Span::def_site()) };
-}
-
-macro_rules! quote_ts {
-    ((@ $($t:tt)*)) => { $($t)* };
-    (::) => {
-        [
-            TokenTree::from(Punct::new(':', Spacing::Joint)),
-            TokenTree::from(Punct::new(':', Spacing::Alone)),
-        ].iter()
-            .cloned()
-            .map(|mut x| {
-                x.set_span(Span::def_site());
-                x
-            })
-            .collect::<TokenStream>()
-    };
-    ($t:tt) => { TokenTree::from(quote_tt!($t)) };
-}
-
-/// Simpler version of the real `quote!` macro, implemented solely
-/// through `macro_rules`, for bootstrapping the real implementation
-/// (see the `quote` function), which does not have access to the
-/// real `quote!` macro due to the `proc_macro` crate not being
-/// able to depend on itself.
-///
-/// Note: supported tokens are a subset of the real `quote!`, but
-/// unquoting is different: instead of `$x`, this uses `(@ expr)`.
-macro_rules! quote {
-    () => { TokenStream::new() };
-    ($($t:tt)*) => {
-        [
-            $(TokenStream::from(quote_ts!($t)),)*
-        ].iter().cloned().collect::<TokenStream>()
-    };
-}
-
-/// Quote a `TokenStream` into a `TokenStream`.
-/// This is the actual implementation of the `quote!()` proc macro.
-///
-/// It is loaded by the compiler in `register_builtin_macros`.
-pub fn quote(stream: TokenStream) -> TokenStream {
-    if stream.is_empty() {
-        return quote!(super::TokenStream::new());
-    }
-    let proc_macro_crate = quote!(crate);
-    let mut after_dollar = false;
-    let tokens = stream
-        .into_iter()
-        .filter_map(|tree| {
-            if after_dollar {
-                after_dollar = false;
-                match tree {
-                    TokenTree::Ident(_) => {
-                        return Some(quote!(Into::<super::TokenStream>::into(
-                        Clone::clone(&(@ tree))),));
-                    }
-                    TokenTree::Punct(ref tt) if tt.as_char() == '$' => {}
-                    _ => panic!("`$` must be followed by an ident or `$` in `quote!`"),
-                }
-            } else if let TokenTree::Punct(ref tt) = tree {
-                if tt.as_char() == '$' {
-                    after_dollar = true;
-                    return None;
-                }
-            }
-
-            Some(quote!(super::TokenStream::from((@ match tree {
-                TokenTree::Punct(tt) => quote!(super::TokenTree::Punct(super::Punct::new(
-                    (@ TokenTree::from(Literal::character(tt.as_char()))),
-                    (@ match tt.spacing() {
-                        Spacing::Alone => quote!(super::Spacing::Alone),
-                        Spacing::Joint => quote!(super::Spacing::Joint),
-                    }),
-                ))),
-                TokenTree::Group(tt) => quote!(super::TokenTree::Group(super::Group::new(
-                    (@ match tt.delimiter() {
-                        Delimiter::Parenthesis => quote!(super::Delimiter::Parenthesis),
-                        Delimiter::Brace => quote!(super::Delimiter::Brace),
-                        Delimiter::Bracket => quote!(super::Delimiter::Bracket),
-                        Delimiter::None => quote!(super::Delimiter::None),
-                    }),
-                    (@ quote(tt.stream())),
-                ))),
-                TokenTree::Ident(tt) => quote!(super::TokenTree::Ident(super::Ident::new(
-                    (@ TokenTree::from(Literal::string(&tt.to_string()))),
-                    (@ quote_span(proc_macro_crate.clone(), tt.span())),
-                ))),
-                TokenTree::Literal(tt) => quote!(super::TokenTree::Literal({
-                    let mut iter = (@ TokenTree::from(Literal::string(&tt.to_string())))
-                        .parse::<super::TokenStream>()
-                        .unwrap()
-                        .into_iter();
-                    if let (Some(super::TokenTree::Literal(mut lit)), None) =
-                        (iter.next(), iter.next())
-                    {
-                        lit.set_span((@ quote_span(proc_macro_crate.clone(), tt.span())));
-                        lit
-                    } else {
-                        unreachable!()
-                    }
-                }))
-            })),))
-        })
-        .collect::<TokenStream>();
-
-    if after_dollar {
-        panic!("unexpected trailing `$` in `quote!`");
-    }
-
-    quote!([(@ tokens)].iter().cloned().collect::<super::TokenStream>())
-}
-
-/// Quote a `Span` into a `TokenStream`.
-/// This is needed to implement a custom quoter.
-pub fn quote_span(proc_macro_crate: TokenStream, span: Span) -> TokenStream {
-    let id = span.save_span();
-    quote!((@ proc_macro_crate ) ::Span::recover_proc_macro_span((@ TokenTree::from(Literal::usize_unsuffixed(id)))))
-}

crates/proc-macro-srv/src/abis/abi_1_64/ra_server.rs

@@ -1,792 +0,0 @@
-//! Rustc proc-macro server implementation with tt
-//!
-//! Based on idea from <https://github.com/fedochet/rust-proc-macro-expander>
-//! The lib-proc-macro server backend is `TokenStream`-agnostic, such that
-//! we could provide any TokenStream implementation.
-//! The original idea from fedochet is using proc-macro2 as backend,
-//! we use tt instead for better integration with RA.
-//!
-//! FIXME: No span and source file information is implemented yet
-
-use super::proc_macro::bridge::{self, server};
-
-use std::collections::HashMap;
-use std::hash::Hash;
-use std::iter::FromIterator;
-use std::ops::Bound;
-use std::{ascii, vec::IntoIter};
-
-type Group = tt::Subtree;
-type TokenTree = tt::TokenTree;
-type Punct = tt::Punct;
-type Spacing = tt::Spacing;
-type Literal = tt::Literal;
-type Span = tt::TokenId;
-
-#[derive(Debug, Default, Clone)]
-pub struct TokenStream {
-    pub token_trees: Vec<TokenTree>,
-}
-
-impl TokenStream {
-    pub fn new() -> Self {
-        TokenStream::default()
-    }
-
-    pub fn with_subtree(subtree: tt::Subtree) -> Self {
-        if subtree.delimiter.is_some() {
-            TokenStream { token_trees: vec![TokenTree::Subtree(subtree)] }
-        } else {
-            TokenStream { token_trees: subtree.token_trees }
-        }
-    }
-
-    pub fn into_subtree(self) -> tt::Subtree {
-        tt::Subtree { delimiter: None, token_trees: self.token_trees }
-    }
-
-    pub fn is_empty(&self) -> bool {
-        self.token_trees.is_empty()
-    }
-}
-
-/// Creates a token stream containing a single token tree.
-impl From<TokenTree> for TokenStream {
-    fn from(tree: TokenTree) -> TokenStream {
-        TokenStream { token_trees: vec![tree] }
-    }
-}
-
-/// Collects a number of token trees into a single stream.
-impl FromIterator<TokenTree> for TokenStream {
-    fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self {
-        trees.into_iter().map(TokenStream::from).collect()
-    }
-}
-
-/// A "flattening" operation on token streams, collects token trees
-/// from multiple token streams into a single stream.
-impl FromIterator<TokenStream> for TokenStream {
-    fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self {
-        let mut builder = TokenStreamBuilder::new();
-        streams.into_iter().for_each(|stream| builder.push(stream));
-        builder.build()
-    }
-}
-
-impl Extend<TokenTree> for TokenStream {
-    fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, trees: I) {
-        self.extend(trees.into_iter().map(TokenStream::from));
-    }
-}
-
-impl Extend<TokenStream> for TokenStream {
-    fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, streams: I) {
-        for item in streams {
-            for tkn in item {
-                match tkn {
-                    tt::TokenTree::Subtree(subtree) if subtree.delimiter.is_none() => {
-                        self.token_trees.extend(subtree.token_trees);
-                    }
-                    _ => {
-                        self.token_trees.push(tkn);
-                    }
-                }
-            }
-        }
-    }
-}
-
-#[derive(Clone)]
-pub struct SourceFile {
-    // FIXME stub
-}
-
-type Level = super::proc_macro::Level;
-type LineColumn = super::proc_macro::LineColumn;
-
-/// A structure representing a diagnostic message and associated children
-/// messages.
-#[derive(Clone, Debug)]
-pub struct Diagnostic {
-    level: Level,
-    message: String,
-    spans: Vec<Span>,
-    children: Vec<Diagnostic>,
-}
-
-impl Diagnostic {
-    /// Creates a new diagnostic with the given `level` and `message`.
-    pub fn new<T: Into<String>>(level: Level, message: T) -> Diagnostic {
-        Diagnostic { level, message: message.into(), spans: vec![], children: vec![] }
-    }
-}
-
-// Rustc Server Ident has to be `Copyable`
-// We use a stub here for bypassing
-#[derive(Hash, Eq, PartialEq, Copy, Clone)]
-pub struct IdentId(u32);
-
-#[derive(Clone, Hash, Eq, PartialEq)]
-struct IdentData(tt::Ident);
-
-#[derive(Default)]
-struct IdentInterner {
-    idents: HashMap<IdentData, u32>,
-    ident_data: Vec<IdentData>,
-}
-
-impl IdentInterner {
-    fn intern(&mut self, data: &IdentData) -> u32 {
-        if let Some(index) = self.idents.get(data) {
-            return *index;
-        }
-
-        let index = self.idents.len() as u32;
-        self.ident_data.push(data.clone());
-        self.idents.insert(data.clone(), index);
-        index
-    }
-
-    fn get(&self, index: u32) -> &IdentData {
-        &self.ident_data[index as usize]
-    }
-
-    #[allow(unused)]
-    fn get_mut(&mut self, index: u32) -> &mut IdentData {
-        self.ident_data.get_mut(index as usize).expect("Should be consistent")
-    }
-}
-
-pub struct TokenStreamBuilder {
-    acc: TokenStream,
-}
-
-/// Public implementation details for the `TokenStream` type, such as iterators.
-pub mod token_stream {
-    use std::str::FromStr;
-
-    use super::{TokenStream, TokenTree};
-
-    /// An iterator over `TokenStream`'s `TokenTree`s.
-    /// The iteration is "shallow", e.g., the iterator doesn't recurse into delimited groups,
-    /// and returns whole groups as token trees.
-    impl IntoIterator for TokenStream {
-        type Item = TokenTree;
-        type IntoIter = super::IntoIter<TokenTree>;
-
-        fn into_iter(self) -> Self::IntoIter {
-            self.token_trees.into_iter()
-        }
-    }
-
-    type LexError = String;
-
-    /// Attempts to break the string into tokens and parse those tokens into a token stream.
-    /// May fail for a number of reasons, for example, if the string contains unbalanced delimiters
-    /// or characters not existing in the language.
-    /// All tokens in the parsed stream get `Span::call_site()` spans.
-    ///
-    /// NOTE: some errors may cause panics instead of returning `LexError`. We reserve the right to
-    /// change these errors into `LexError`s later.
-    impl FromStr for TokenStream {
-        type Err = LexError;
-
-        fn from_str(src: &str) -> Result<TokenStream, LexError> {
-            let (subtree, _token_map) =
-                mbe::parse_to_token_tree(src).ok_or("Failed to parse from mbe")?;
-
-            let subtree = subtree_replace_token_ids_with_unspecified(subtree);
-            Ok(TokenStream::with_subtree(subtree))
-        }
-    }
-
-    impl ToString for TokenStream {
-        fn to_string(&self) -> String {
-            tt::pretty(&self.token_trees)
-        }
-    }
-
-    fn subtree_replace_token_ids_with_unspecified(subtree: tt::Subtree) -> tt::Subtree {
-        tt::Subtree {
-            delimiter: subtree
-                .delimiter
-                .map(|d| tt::Delimiter { id: tt::TokenId::unspecified(), ..d }),
-            token_trees: subtree
-                .token_trees
-                .into_iter()
-                .map(token_tree_replace_token_ids_with_unspecified)
-                .collect(),
-        }
-    }
-
-    fn token_tree_replace_token_ids_with_unspecified(tt: tt::TokenTree) -> tt::TokenTree {
-        match tt {
-            tt::TokenTree::Leaf(leaf) => {
-                tt::TokenTree::Leaf(leaf_replace_token_ids_with_unspecified(leaf))
-            }
-            tt::TokenTree::Subtree(subtree) => {
-                tt::TokenTree::Subtree(subtree_replace_token_ids_with_unspecified(subtree))
-            }
-        }
-    }
-
-    fn leaf_replace_token_ids_with_unspecified(leaf: tt::Leaf) -> tt::Leaf {
-        match leaf {
-            tt::Leaf::Literal(lit) => {
-                tt::Leaf::Literal(tt::Literal { id: tt::TokenId::unspecified(), ..lit })
-            }
-            tt::Leaf::Punct(punct) => {
-                tt::Leaf::Punct(tt::Punct { id: tt::TokenId::unspecified(), ..punct })
-            }
-            tt::Leaf::Ident(ident) => {
-                tt::Leaf::Ident(tt::Ident { id: tt::TokenId::unspecified(), ..ident })
-            }
-        }
-    }
-}
-
-impl TokenStreamBuilder {
-    fn new() -> TokenStreamBuilder {
-        TokenStreamBuilder { acc: TokenStream::new() }
-    }
-
-    fn push(&mut self, stream: TokenStream) {
-        self.acc.extend(stream.into_iter())
-    }
-
-    fn build(self) -> TokenStream {
-        self.acc
-    }
-}
-
-pub struct FreeFunctions;
-
-#[derive(Clone)]
-pub struct TokenStreamIter {
-    trees: IntoIter<TokenTree>,
-}
-
-#[derive(Default)]
-pub struct RustAnalyzer {
-    ident_interner: IdentInterner,
-    // FIXME: store span information here.
-}
-
-impl server::Types for RustAnalyzer {
-    type FreeFunctions = FreeFunctions;
-    type TokenStream = TokenStream;
-    type Ident = IdentId;
-    type Literal = Literal;
-    type SourceFile = SourceFile;
-    type Diagnostic = Diagnostic;
-    type Span = Span;
-    type MultiSpan = Vec<Span>;
-}
-
-impl server::FreeFunctions for RustAnalyzer {
-    fn track_env_var(&mut self, _var: &str, _value: Option<&str>) {
-        // FIXME: track env var accesses
-        // https://github.com/rust-lang/rust/pull/71858
-    }
-    fn track_path(&mut self, _path: &str) {}
-}
-
-impl server::TokenStream for RustAnalyzer {
-    fn is_empty(&mut self, stream: &Self::TokenStream) -> bool {
-        stream.is_empty()
-    }
-    fn from_str(&mut self, src: &str) -> Self::TokenStream {
-        use std::str::FromStr;
-
-        Self::TokenStream::from_str(src).expect("cannot parse string")
-    }
-    fn to_string(&mut self, stream: &Self::TokenStream) -> String {
-        stream.to_string()
-    }
-    fn from_token_tree(
-        &mut self,
-        tree: bridge::TokenTree<Self::TokenStream, Self::Span, Self::Ident, Self::Literal>,
-    ) -> Self::TokenStream {
-        match tree {
-            bridge::TokenTree::Group(group) => {
-                let group = Group {
-                    delimiter: delim_to_internal(group.delimiter),
-                    token_trees: match group.stream {
-                        Some(stream) => stream.into_iter().collect(),
-                        None => Vec::new(),
-                    },
-                };
-                let tree = TokenTree::from(group);
-                Self::TokenStream::from_iter(vec![tree])
-            }
-
-            bridge::TokenTree::Ident(IdentId(index)) => {
-                let IdentData(ident) = self.ident_interner.get(index).clone();
-                let ident: tt::Ident = ident;
-                let leaf = tt::Leaf::from(ident);
-                let tree = TokenTree::from(leaf);
-                Self::TokenStream::from_iter(vec![tree])
-            }
-
-            bridge::TokenTree::Literal(literal) => {
-                let leaf = tt::Leaf::from(literal);
-                let tree = TokenTree::from(leaf);
-                Self::TokenStream::from_iter(vec![tree])
-            }
-
-            bridge::TokenTree::Punct(p) => {
-                let punct = tt::Punct {
-                    char: p.ch as char,
-                    spacing: if p.joint { Spacing::Joint } else { Spacing::Alone },
-                    id: p.span,
-                };
-                let leaf = tt::Leaf::from(punct);
-                let tree = TokenTree::from(leaf);
-                Self::TokenStream::from_iter(vec![tree])
-            }
-        }
-    }
-
-    fn expand_expr(&mut self, self_: &Self::TokenStream) -> Result<Self::TokenStream, ()> {
-        Ok(self_.clone())
-    }
-
-    fn concat_trees(
-        &mut self,
-        base: Option<Self::TokenStream>,
-        trees: Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Ident, Self::Literal>>,
-    ) -> Self::TokenStream {
-        let mut builder = TokenStreamBuilder::new();
-        if let Some(base) = base {
-            builder.push(base);
-        }
-        for tree in trees {
-            builder.push(self.from_token_tree(tree));
-        }
-        builder.build()
-    }
-
-    fn concat_streams(
-        &mut self,
-        base: Option<Self::TokenStream>,
-        streams: Vec<Self::TokenStream>,
-    ) -> Self::TokenStream {
-        let mut builder = TokenStreamBuilder::new();
-        if let Some(base) = base {
-            builder.push(base);
-        }
-        for stream in streams {
-            builder.push(stream);
-        }
-        builder.build()
-    }
-
-    fn into_trees(
-        &mut self,
-        stream: Self::TokenStream,
-    ) -> Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Ident, Self::Literal>> {
-        stream
-            .into_iter()
-            .map(|tree| match tree {
-                tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) => {
-                    bridge::TokenTree::Ident(IdentId(self.ident_interner.intern(&IdentData(ident))))
-                }
-                tt::TokenTree::Leaf(tt::Leaf::Literal(lit)) => bridge::TokenTree::Literal(lit),
-                tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) => {
-                    bridge::TokenTree::Punct(bridge::Punct {
-                        ch: punct.char as u8,
-                        joint: punct.spacing == Spacing::Joint,
-                        span: punct.id,
-                    })
-                }
-                tt::TokenTree::Subtree(subtree) => bridge::TokenTree::Group(bridge::Group {
-                    delimiter: delim_to_external(subtree.delimiter),
-                    stream: if subtree.token_trees.is_empty() {
-                        None
-                    } else {
-                        Some(subtree.token_trees.into_iter().collect())
-                    },
-                    span: bridge::DelimSpan::from_single(
-                        subtree.delimiter.map_or(Span::unspecified(), |del| del.id),
-                    ),
-                }),
-            })
-            .collect()
-    }
-}
-
-fn delim_to_internal(d: bridge::Delimiter) -> Option<tt::Delimiter> {
-    let kind = match d {
-        bridge::Delimiter::Parenthesis => tt::DelimiterKind::Parenthesis,
-        bridge::Delimiter::Brace => tt::DelimiterKind::Brace,
-        bridge::Delimiter::Bracket => tt::DelimiterKind::Bracket,
-        bridge::Delimiter::None => return None,
-    };
-    Some(tt::Delimiter { id: tt::TokenId::unspecified(), kind })
-}
-
-fn delim_to_external(d: Option<tt::Delimiter>) -> bridge::Delimiter {
-    match d.map(|it| it.kind) {
-        Some(tt::DelimiterKind::Parenthesis) => bridge::Delimiter::Parenthesis,
-        Some(tt::DelimiterKind::Brace) => bridge::Delimiter::Brace,
-        Some(tt::DelimiterKind::Bracket) => bridge::Delimiter::Bracket,
-        None => bridge::Delimiter::None,
-    }
-}
-
-fn spacing_to_internal(spacing: bridge::Spacing) -> Spacing {
-    match spacing {
-        bridge::Spacing::Alone => Spacing::Alone,
-        bridge::Spacing::Joint => Spacing::Joint,
-    }
-}
-
-fn spacing_to_external(spacing: Spacing) -> bridge::Spacing {
-    match spacing {
-        Spacing::Alone => bridge::Spacing::Alone,
-        Spacing::Joint => bridge::Spacing::Joint,
-    }
-}
-
-impl server::Ident for RustAnalyzer {
-    fn new(&mut self, string: &str, span: Self::Span, _is_raw: bool) -> Self::Ident {
-        IdentId(self.ident_interner.intern(&IdentData(tt::Ident { text: string.into(), id: span })))
-    }
-
-    fn span(&mut self, ident: Self::Ident) -> Self::Span {
-        self.ident_interner.get(ident.0).0.id
-    }
-    fn with_span(&mut self, ident: Self::Ident, span: Self::Span) -> Self::Ident {
-        let data = self.ident_interner.get(ident.0);
-        let new = IdentData(tt::Ident { id: span, ..data.0.clone() });
-        IdentId(self.ident_interner.intern(&new))
-    }
-}
-
-impl server::Literal for RustAnalyzer {
-    fn debug_kind(&mut self, _literal: &Self::Literal) -> String {
-        // r-a: debug_kind and suffix are unsupported; corresponding client code has been changed to not call these.
-        // They must still be present to be ABI-compatible and work with upstream proc_macro.
-        "".to_owned()
-    }
-    fn from_str(&mut self, s: &str) -> Result<Self::Literal, ()> {
-        Ok(Literal { text: s.into(), id: tt::TokenId::unspecified() })
-    }
-    fn symbol(&mut self, literal: &Self::Literal) -> String {
-        literal.text.to_string()
-    }
-    fn suffix(&mut self, _literal: &Self::Literal) -> Option<String> {
-        None
-    }
-
-    fn to_string(&mut self, literal: &Self::Literal) -> String {
-        literal.to_string()
-    }
-
-    fn integer(&mut self, n: &str) -> Self::Literal {
-        let n = match n.parse::<i128>() {
-            Ok(n) => n.to_string(),
-            Err(_) => n.parse::<u128>().unwrap().to_string(),
-        };
-        Literal { text: n.into(), id: tt::TokenId::unspecified() }
-    }
-
-    fn typed_integer(&mut self, n: &str, kind: &str) -> Self::Literal {
-        macro_rules! def_suffixed_integer {
-            ($kind:ident, $($ty:ty),*) => {
-                match $kind {
-                    $(
-                        stringify!($ty) => {
-                            let n: $ty = n.parse().unwrap();
-                            format!(concat!("{}", stringify!($ty)), n)
-                        }
-                    )*
-                    _ => unimplemented!("unknown args for typed_integer: n {}, kind {}", n, $kind),
-                }
-            }
-        }
-
-        let text = def_suffixed_integer! {kind, u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize};
-
-        Literal { text: text.into(), id: tt::TokenId::unspecified() }
-    }
-
-    fn float(&mut self, n: &str) -> Self::Literal {
-        let n: f64 = n.parse().unwrap();
-        let mut text = f64::to_string(&n);
-        if !text.contains('.') {
-            text += ".0"
-        }
-        Literal { text: text.into(), id: tt::TokenId::unspecified() }
-    }
-
-    fn f32(&mut self, n: &str) -> Self::Literal {
-        let n: f32 = n.parse().unwrap();
-        let text = format!("{}f32", n);
-        Literal { text: text.into(), id: tt::TokenId::unspecified() }
-    }
-
-    fn f64(&mut self, n: &str) -> Self::Literal {
-        let n: f64 = n.parse().unwrap();
-        let text = format!("{}f64", n);
-        Literal { text: text.into(), id: tt::TokenId::unspecified() }
-    }
-
-    fn string(&mut self, string: &str) -> Self::Literal {
-        let mut escaped = String::new();
-        for ch in string.chars() {
-            escaped.extend(ch.escape_debug());
-        }
-        Literal { text: format!("\"{}\"", escaped).into(), id: tt::TokenId::unspecified() }
-    }
-
-    fn character(&mut self, ch: char) -> Self::Literal {
-        Literal { text: format!("'{}'", ch).into(), id: tt::TokenId::unspecified() }
-    }
-
-    fn byte_string(&mut self, bytes: &[u8]) -> Self::Literal {
-        let string = bytes
-            .iter()
-            .cloned()
-            .flat_map(ascii::escape_default)
-            .map(Into::<char>::into)
-            .collect::<String>();
-
-        Literal { text: format!("b\"{}\"", string).into(), id: tt::TokenId::unspecified() }
-    }
-
-    fn span(&mut self, literal: &Self::Literal) -> Self::Span {
-        literal.id
-    }
-
-    fn set_span(&mut self, literal: &mut Self::Literal, span: Self::Span) {
-        literal.id = span;
-    }
-
-    fn subspan(
-        &mut self,
-        _literal: &Self::Literal,
-        _start: Bound<usize>,
-        _end: Bound<usize>,
-    ) -> Option<Self::Span> {
-        // FIXME handle span
-        None
-    }
-}
-
-impl server::SourceFile for RustAnalyzer {
-    // FIXME these are all stubs
-    fn eq(&mut self, _file1: &Self::SourceFile, _file2: &Self::SourceFile) -> bool {
-        true
-    }
-    fn path(&mut self, _file: &Self::SourceFile) -> String {
-        String::new()
-    }
-    fn is_real(&mut self, _file: &Self::SourceFile) -> bool {
-        true
-    }
-}
-
-impl server::Diagnostic for RustAnalyzer {
-    fn new(&mut self, level: Level, msg: &str, spans: Self::MultiSpan) -> Self::Diagnostic {
-        let mut diag = Diagnostic::new(level, msg);
-        diag.spans = spans;
-        diag
-    }
-
-    fn sub(
-        &mut self,
-        _diag: &mut Self::Diagnostic,
-        _level: Level,
-        _msg: &str,
-        _spans: Self::MultiSpan,
-    ) {
-        // FIXME handle diagnostic
-        //
-    }
-
-    fn emit(&mut self, _diag: Self::Diagnostic) {
-        // FIXME handle diagnostic
-        // diag.emit()
-    }
-}
-
-impl server::Span for RustAnalyzer {
-    fn debug(&mut self, span: Self::Span) -> String {
-        format!("{:?}", span.0)
-    }
-    fn source_file(&mut self, _span: Self::Span) -> Self::SourceFile {
-        SourceFile {}
-    }
-    fn save_span(&mut self, _span: Self::Span) -> usize {
-        // FIXME stub
-        0
-    }
-    fn recover_proc_macro_span(&mut self, _id: usize) -> Self::Span {
-        // FIXME stub
-        tt::TokenId::unspecified()
-    }
-    /// Recent feature, not yet in the proc_macro
-    ///
-    /// See PR:
-    /// https://github.com/rust-lang/rust/pull/55780
-    fn source_text(&mut self, _span: Self::Span) -> Option<String> {
-        None
-    }
-
-    fn parent(&mut self, _span: Self::Span) -> Option<Self::Span> {
-        // FIXME handle span
-        None
-    }
-    fn source(&mut self, span: Self::Span) -> Self::Span {
-        // FIXME handle span
-        span
-    }
-    fn start(&mut self, _span: Self::Span) -> LineColumn {
-        // FIXME handle span
-        LineColumn { line: 0, column: 0 }
-    }
-    fn end(&mut self, _span: Self::Span) -> LineColumn {
-        // FIXME handle span
-        LineColumn { line: 0, column: 0 }
-    }
-    fn join(&mut self, first: Self::Span, _second: Self::Span) -> Option<Self::Span> {
-        // Just return the first span again, because some macros will unwrap the result.
-        Some(first)
-    }
-    fn resolved_at(&mut self, _span: Self::Span, _at: Self::Span) -> Self::Span {
-        // FIXME handle span
-        tt::TokenId::unspecified()
-    }
-
-    fn after(&mut self, _self_: Self::Span) -> Self::Span {
-        tt::TokenId::unspecified()
-    }
-
-    fn before(&mut self, _self_: Self::Span) -> Self::Span {
-        tt::TokenId::unspecified()
-    }
-}
-
-impl server::MultiSpan for RustAnalyzer {
-    fn new(&mut self) -> Self::MultiSpan {
-        // FIXME handle span
-        vec![]
-    }
-
-    fn push(&mut self, other: &mut Self::MultiSpan, span: Self::Span) {
-        //TODP
-        other.push(span)
-    }
-}
-
-impl server::Server for RustAnalyzer {
-    fn globals(&mut self) -> bridge::ExpnGlobals<Self::Span> {
-        bridge::ExpnGlobals {
-            def_site: Span::unspecified(),
-            call_site: Span::unspecified(),
-            mixed_site: Span::unspecified(),
-        }
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::super::proc_macro::bridge::server::Literal;
-    use super::*;
-
-    #[test]
-    fn test_ra_server_literals() {
-        let mut srv = RustAnalyzer { ident_interner: IdentInterner::default() };
-        assert_eq!(srv.integer("1234").text, "1234");
-
-        assert_eq!(srv.typed_integer("12", "u8").text, "12u8");
-        assert_eq!(srv.typed_integer("255", "u16").text, "255u16");
-        assert_eq!(srv.typed_integer("1234", "u32").text, "1234u32");
-        assert_eq!(srv.typed_integer("15846685", "u64").text, "15846685u64");
-        assert_eq!(srv.typed_integer("15846685258", "u128").text, "15846685258u128");
-        assert_eq!(srv.typed_integer("156788984", "usize").text, "156788984usize");
-        assert_eq!(srv.typed_integer("127", "i8").text, "127i8");
-        assert_eq!(srv.typed_integer("255", "i16").text, "255i16");
-        assert_eq!(srv.typed_integer("1234", "i32").text, "1234i32");
-        assert_eq!(srv.typed_integer("15846685", "i64").text, "15846685i64");
-        assert_eq!(srv.typed_integer("15846685258", "i128").text, "15846685258i128");
-        assert_eq!(srv.float("0").text, "0.0");
-        assert_eq!(srv.float("15684.5867").text, "15684.5867");
-        assert_eq!(srv.f32("15684.58").text, "15684.58f32");
-        assert_eq!(srv.f64("15684.58").text, "15684.58f64");
-
-        assert_eq!(srv.string("hello_world").text, "\"hello_world\"");
-        assert_eq!(srv.character('c').text, "'c'");
-        assert_eq!(srv.byte_string(b"1234586\x88").text, "b\"1234586\\x88\"");
-
-        // u128::max
-        assert_eq!(
-            srv.integer("340282366920938463463374607431768211455").text,
-            "340282366920938463463374607431768211455"
-        );
-        // i128::min
-        assert_eq!(
-            srv.integer("-170141183460469231731687303715884105728").text,
-            "-170141183460469231731687303715884105728"
-        );
-    }
-
-    #[test]
-    fn test_ra_server_to_string() {
-        let s = TokenStream {
-            token_trees: vec![
-                tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
-                    text: "struct".into(),
-                    id: tt::TokenId::unspecified(),
-                })),
-                tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
-                    text: "T".into(),
-                    id: tt::TokenId::unspecified(),
-                })),
-                tt::TokenTree::Subtree(tt::Subtree {
-                    delimiter: Some(tt::Delimiter {
-                        id: tt::TokenId::unspecified(),
-                        kind: tt::DelimiterKind::Brace,
-                    }),
-                    token_trees: vec![],
-                }),
-            ],
-        };
-
-        assert_eq!(s.to_string(), "struct T {}");
-    }
-
-    #[test]
-    fn test_ra_server_from_str() {
-        use std::str::FromStr;
-        let subtree_paren_a = tt::TokenTree::Subtree(tt::Subtree {
-            delimiter: Some(tt::Delimiter {
-                id: tt::TokenId::unspecified(),
-                kind: tt::DelimiterKind::Parenthesis,
-            }),
-            token_trees: vec![tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
-                text: "a".into(),
-                id: tt::TokenId::unspecified(),
-            }))],
-        });
-
-        let t1 = TokenStream::from_str("(a)").unwrap();
-        assert_eq!(t1.token_trees.len(), 1);
-        assert_eq!(t1.token_trees[0], subtree_paren_a);
-
-        let t2 = TokenStream::from_str("(a);").unwrap();
-        assert_eq!(t2.token_trees.len(), 2);
-        assert_eq!(t2.token_trees[0], subtree_paren_a);
-
-        let underscore = TokenStream::from_str("_").unwrap();
-        assert_eq!(
-            underscore.token_trees[0],
-            tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
-                text: "_".into(),
-                id: tt::TokenId::unspecified(),
-            }))
-        );
-    }
-}

crates/proc-macro-srv/src/abis/abi_sysroot/ra_server.rs

@@ -20,7 +20,7 @@ use token_stream::TokenStreamBuilder;
 mod symbol;
 pub use symbol::*;
 
-use std::{iter::FromIterator, ops::Bound};
+use std::ops::Bound;
 
 type Group = tt::Subtree;
 type TokenTree = tt::TokenTree;

crates/proc-macro-srv/src/abis/mod.rs

@@ -25,7 +25,6 @@
 
 mod abi_1_58;
 mod abi_1_63;
-mod abi_1_64;
 #[cfg(feature = "sysroot-abi")]
 mod abi_sysroot;
 
@@ -34,12 +33,11 @@ include!(concat!(env!("OUT_DIR"), "/rustc_version.rs"));
 
 // Used by `test/utils.rs`
 #[cfg(test)]
-pub(crate) use abi_1_64::TokenStream as TestTokenStream;
+pub(crate) use abi_1_63::TokenStream as TestTokenStream;
 
 use super::dylib::LoadProcMacroDylibError;
 pub(crate) use abi_1_58::Abi as Abi_1_58;
 pub(crate) use abi_1_63::Abi as Abi_1_63;
-pub(crate) use abi_1_64::Abi as Abi_1_64;
 #[cfg(feature = "sysroot-abi")]
 pub(crate) use abi_sysroot::Abi as Abi_Sysroot;
 use libloading::Library;
@@ -58,7 +56,6 @@ impl PanicMessage {
 pub(crate) enum Abi {
     Abi1_58(Abi_1_58),
     Abi1_63(Abi_1_63),
-    Abi1_64(Abi_1_64),
     #[cfg(feature = "sysroot-abi")]
     AbiSysroot(Abi_Sysroot),
 }
@@ -120,10 +117,6 @@ impl Abi {
                 let inner = unsafe { Abi_1_63::from_lib(lib, symbol_name) }?;
                 Ok(Abi::Abi1_63(inner))
             }
-            (1, 64..) => {
-                let inner = unsafe { Abi_1_64::from_lib(lib, symbol_name) }?;
-                Ok(Abi::Abi1_64(inner))
-            }
             _ => Err(LoadProcMacroDylibError::UnsupportedABI),
         }
     }
@@ -137,7 +130,6 @@ impl Abi {
         match self {
             Self::Abi1_58(abi) => abi.expand(macro_name, macro_body, attributes),
             Self::Abi1_63(abi) => abi.expand(macro_name, macro_body, attributes),
-            Self::Abi1_64(abi) => abi.expand(macro_name, macro_body, attributes),
             #[cfg(feature = "sysroot-abi")]
             Self::AbiSysroot(abi) => abi.expand(macro_name, macro_body, attributes),
         }
@@ -147,7 +139,6 @@ impl Abi {
         match self {
             Self::Abi1_58(abi) => abi.list_macros(),
             Self::Abi1_63(abi) => abi.list_macros(),
-            Self::Abi1_64(abi) => abi.list_macros(),
             #[cfg(feature = "sysroot-abi")]
             Self::AbiSysroot(abi) => abi.list_macros(),
         }

crates/proc-macro-srv/src/dylib.rs

@@ -1,7 +1,6 @@
 //! Handles dynamic library loading for proc macro
 
 use std::{
-    convert::TryInto,
     fmt,
     fs::File,
     io,

crates/proc-macro-srv/src/tests/mod.rs

@@ -19,7 +19,7 @@ fn test_derive_error() {
         expect![[r##"
             SUBTREE $
               IDENT   compile_error 4294967295
-              PUNCH   ! [alone] 4294967295
+              PUNCH   ! [joint] 4294967295
               SUBTREE () 4294967295
                 LITERAL "#[derive(DeriveError)] struct S ;" 4294967295
               PUNCH   ; [alone] 4294967295"##]],
@@ -109,7 +109,7 @@ fn test_fn_like_macro_clone_literals() {
               PUNCH   , [alone] 4294967295
               LITERAL 2_u32 4294967295
               PUNCH   , [alone] 4294967295
-              PUNCH   - [alone] 4294967295
+              PUNCH   - [joint] 4294967295
               LITERAL 4i64 4294967295
               PUNCH   , [alone] 4294967295
               LITERAL 3.14f32 4294967295
@@ -130,7 +130,7 @@ fn test_attr_macro() {
         expect![[r##"
             SUBTREE $
               IDENT   compile_error 4294967295
-              PUNCH   ! [alone] 4294967295
+              PUNCH   ! [joint] 4294967295
               SUBTREE () 4294967295
                 LITERAL "#[attr_error(some arguments)] mod m {}" 4294967295
               PUNCH   ; [alone] 4294967295"##]],

crates/project-model/src/build_scripts.rs

@@ -12,6 +12,7 @@ use cargo_metadata::{camino::Utf8Path, Message};
 use la_arena::ArenaMap;
 use paths::AbsPathBuf;
 use rustc_hash::FxHashMap;
+use semver::Version;
 use serde::Deserialize;
 
 use crate::{cfg_flag::CfgFlag, CargoConfig, CargoWorkspace, Package};
@@ -77,9 +78,32 @@ impl WorkspaceBuildScripts {
         config: &CargoConfig,
         workspace: &CargoWorkspace,
         progress: &dyn Fn(String),
+        toolchain: &Option<Version>,
     ) -> io::Result<WorkspaceBuildScripts> {
-        let mut cmd = Self::build_command(config);
+        const RUST_1_62: Version = Version::new(1, 62, 0);
 
+        match Self::run_(Self::build_command(config), config, workspace, progress) {
+            Ok(WorkspaceBuildScripts { error: Some(error), .. })
+                if toolchain.as_ref().map_or(false, |it| *it >= RUST_1_62) =>
+            {
+                // building build scripts failed, attempt to build with --keep-going so
+                // that we potentially get more build data
+                let mut cmd = Self::build_command(config);
+                cmd.args(&["-Z", "unstable-options", "--keep-going"]).env("RUSTC_BOOTSTRAP", "1");
+                let mut res = Self::run_(cmd, config, workspace, progress)?;
+                res.error = Some(error);
+                Ok(res)
+            }
+            res => res,
+        }
+    }
+
+    fn run_(
+        mut cmd: Command,
+        config: &CargoConfig,
+        workspace: &CargoWorkspace,
+        progress: &dyn Fn(String),
+    ) -> io::Result<WorkspaceBuildScripts> {
         if config.wrap_rustc_in_build_scripts {
             // Setup RUSTC_WRAPPER to point to `rust-analyzer` binary itself. We use
             // that to compile only proc macros and build scripts during the initial

crates/project-model/src/tests.rs

@@ -28,6 +28,7 @@ fn load_cargo_with_overrides(file: &str, cfg_overrides: CfgOverrides) -> CrateGr
         rustc: None,
         rustc_cfg: Vec::new(),
         cfg_overrides,
+        toolchain: None,
     };
     to_crate_graph(project_workspace)
 }

crates/project-model/src/workspace.rs

@@ -12,6 +12,7 @@ use base_db::{
 use cfg::{CfgDiff, CfgOptions};
 use paths::{AbsPath, AbsPathBuf};
 use rustc_hash::{FxHashMap, FxHashSet};
+use semver::Version;
 use stdx::always;
 
 use crate::{
@@ -77,6 +78,7 @@ pub enum ProjectWorkspace {
         /// different target.
         rustc_cfg: Vec<CfgFlag>,
         cfg_overrides: CfgOverrides,
+        toolchain: Option<Version>,
     },
     /// Project workspace was manually specified using a `rust-project.json` file.
     Json { project: ProjectJson, sysroot: Option<Sysroot>, rustc_cfg: Vec<CfgFlag> },
@@ -105,6 +107,7 @@ impl fmt::Debug for ProjectWorkspace {
                 rustc,
                 rustc_cfg,
                 cfg_overrides,
+                toolchain,
             } => f
                 .debug_struct("Cargo")
                 .field("root", &cargo.workspace_root().file_name())
@@ -116,6 +119,7 @@ impl fmt::Debug for ProjectWorkspace {
                 )
                 .field("n_rustc_cfg", &rustc_cfg.len())
                 .field("n_cfg_overrides", &cfg_overrides.len())
+                .field("toolchain", &toolchain)
                 .finish(),
             ProjectWorkspace::Json { project, sysroot, rustc_cfg } => {
                 let mut debug_struct = f.debug_struct("Json");
@@ -160,6 +164,9 @@ impl ProjectWorkspace {
                     cmd.arg("--version");
                     cmd
                 })?;
+                let toolchain = cargo_version
+                    .get("cargo ".len()..)
+                    .and_then(|it| Version::parse(it.split_whitespace().next()?).ok());
 
                 let meta = CargoWorkspace::fetch_metadata(
                     &cargo_toml,
@@ -169,9 +176,9 @@ impl ProjectWorkspace {
                 )
                 .with_context(|| {
                     format!(
-                        "Failed to read Cargo metadata from Cargo.toml file {}, {}",
+                        "Failed to read Cargo metadata from Cargo.toml file {}, {:?}",
                         cargo_toml.display(),
-                        cargo_version
+                        toolchain
                     )
                 })?;
                 let cargo = CargoWorkspace::new(meta);
@@ -219,6 +226,7 @@ impl ProjectWorkspace {
                     rustc,
                     rustc_cfg,
                     cfg_overrides,
+                    toolchain,
                 }
             }
         };
@@ -271,8 +279,8 @@ impl ProjectWorkspace {
         progress: &dyn Fn(String),
     ) -> Result<WorkspaceBuildScripts> {
         match self {
-            ProjectWorkspace::Cargo { cargo, .. } => {
-                WorkspaceBuildScripts::run(config, cargo, progress).with_context(|| {
+            ProjectWorkspace::Cargo { cargo, toolchain, .. } => {
+                WorkspaceBuildScripts::run(config, cargo, progress, toolchain).with_context(|| {
                     format!("Failed to run build scripts for {}", &cargo.workspace_root().display())
                 })
             }
@@ -320,6 +328,7 @@ impl ProjectWorkspace {
                 rustc_cfg: _,
                 cfg_overrides: _,
                 build_scripts,
+                toolchain: _,
             } => {
                 cargo
                     .packages()
@@ -425,6 +434,7 @@ impl ProjectWorkspace {
                 rustc_cfg,
                 cfg_overrides,
                 build_scripts,
+                toolchain: _,
             } => cargo_to_crate_graph(
                 rustc_cfg.clone(),
                 cfg_overrides,

crates/rust-analyzer/src/bin/rustc_wrapper.rs

@@ -17,6 +17,11 @@ pub(crate) fn run_rustc_skipping_cargo_checking(
     rustc_executable: OsString,
     args: Vec<OsString>,
 ) -> io::Result<ExitCode> {
+    // `CARGO_CFG_TARGET_ARCH` is only set by cargo when executing build scripts
+    // We don't want to exit out checks unconditionally with success if a build
+    // script tries to invoke checks themselves
+    // See https://github.com/rust-lang/rust-analyzer/issues/12973 for context
+    let not_invoked_by_build_script = std::env::var_os("CARGO_CFG_TARGET_ARCH").is_none();
     let is_cargo_check = args.iter().any(|arg| {
         let arg = arg.to_string_lossy();
         // `cargo check` invokes `rustc` with `--emit=metadata` argument.
@@ -29,7 +34,7 @@ pub(crate) fn run_rustc_skipping_cargo_checking(
         //            The default output filename is CRATE_NAME.rmeta.
         arg.starts_with("--emit=") && arg.contains("metadata") && !arg.contains("link")
     });
-    if is_cargo_check {
+    if not_invoked_by_build_script && is_cargo_check {
         return Ok(ExitCode(Some(0)));
     }
     run_rustc(rustc_executable, args)

crates/rust-analyzer/src/cli/diagnostics.rs

@@ -43,7 +43,7 @@ impl flags::Diagnostics {
                 println!("processing crate: {}, module: {}", crate_name, _vfs.file_path(file_id));
                 for diagnostic in analysis
                     .diagnostics(
-                        &DiagnosticsConfig::default(),
+                        &DiagnosticsConfig::test_sample(),
                         AssistResolveStrategy::None,
                         file_id,
                     )

crates/rust-analyzer/src/cli/flags.rs

@@ -10,6 +10,10 @@ xflags::xflags! {
     src "./src/cli/flags.rs"
 
     /// LSP server for the Rust programming language.
+    ///
+    /// Subcommands and their flags do not provide any stability guarantees and may be removed or
+    /// changed without notice. Top-level flags that are not are marked as [Unstable] provide
+    /// backwards-compatibility and may be relied on.
     cmd rust-analyzer {
         /// Verbosity level, can be repeated multiple times.
         repeated -v, --verbose
@@ -21,7 +25,7 @@ xflags::xflags! {
         /// Flush log records to the file immediately.
         optional --no-log-buffering
 
-        /// Wait until a debugger is attached to (requires debug build).
+        /// [Unstable] Wait until a debugger is attached to (requires debug build).
         optional --wait-dbg
 
         default cmd lsp-server {

crates/rust-analyzer/src/config.rs

@@ -881,6 +881,7 @@ impl Config {
                 ExprFillDefaultDef::Todo => ExprFillDefaultMode::Todo,
                 ExprFillDefaultDef::Default => ExprFillDefaultMode::Default,
             },
+            insert_use: self.insert_use_config(),
         }
     }