Refactor ide handling for paths in derive inputs

crates/ide/src/doc_links.rs

@@ -4,7 +4,7 @@ mod intra_doc_links;
 
 use either::Either;
 use pulldown_cmark::{BrokenLink, CowStr, Event, InlineStr, LinkType, Options, Parser, Tag};
-use pulldown_cmark_to_cmark::{cmark_with_options, Options as CmarkOptions};
+use pulldown_cmark_to_cmark::{cmark_with_options, Options as CMarkOptions};
 use stdx::format_to;
 use url::Url;
 
@@ -65,7 +65,7 @@ pub(crate) fn rewrite_links(db: &RootDatabase, markdown: &str, definition: Defin
         doc,
         &mut out,
         None,
-        CmarkOptions { code_block_backticks: 3, ..Default::default() },
+        CMarkOptions { code_block_backticks: 3, ..Default::default() },
     )
     .ok();
     out
@@ -103,7 +103,7 @@ pub(crate) fn remove_links(markdown: &str) -> String {
         doc,
         &mut out,
         None,
-        CmarkOptions { code_block_backticks: 3, ..Default::default() },
+        CMarkOptions { code_block_backticks: 3, ..Default::default() },
     )
     .ok();
     out

crates/ide/src/goto_definition.rs

@@ -1371,6 +1371,7 @@ impl Twait for Stwuct {
     fn goto_def_derive_input() {
         check(
             r#"
+//- minicore:derive
 #[rustc_builtin_macro]
 pub macro Copy {}
        // ^^^^
@@ -1380,6 +1381,7 @@ struct Foo;
         );
         check(
             r#"
+//- minicore:derive
 mod foo {
     #[rustc_builtin_macro]
     pub macro Copy {}

crates/ide/src/hover/tests.rs

@@ -3651,6 +3651,7 @@ use crate as foo$0;
 fn hover_attribute_in_macro() {
     check(
         r#"
+//- minicore:derive
 macro_rules! identity {
     ($struct:item) => {
         $struct
@@ -3681,6 +3682,7 @@ identity!{
 fn hover_derive_input() {
     check(
         r#"
+//- minicore:derive
 #[rustc_builtin_macro]
 pub macro Copy {}
 #[derive(Copy$0)]
@@ -3700,6 +3702,7 @@ struct Foo;
     );
     check(
         r#"
+//- minicore:derive
 mod foo {
     #[rustc_builtin_macro]
     pub macro Copy {}

crates/ide/src/static_index.rs

@@ -266,12 +266,10 @@ enum E { X(Foo) }
     fn derives() {
         check_all_ranges(
             r#"
+//- minicore:derive
 #[rustc_builtin_macro]
 pub macro Copy {}
         //^^^^
-#[rustc_builtin_macro]
-pub macro derive {}
-        //^^^^^^
 #[derive(Copy)]
 //^^^^^^ ^^^^
 struct Hello(i32);

crates/ide/src/syntax_highlighting/highlight.rs

@@ -3,7 +3,7 @@
 use hir::{AsAssocItem, HasVisibility, Semantics};
 use ide_db::{
     defs::{Definition, NameClass, NameRefClass},
-    helpers::{try_resolve_derive_input_at, FamousDefs},
+    helpers::{try_resolve_derive_input, FamousDefs},
     RootDatabase, SymbolKind,
 };
 use rustc_hash::FxHashMap;
@@ -56,8 +56,8 @@ fn token(
             T![?] => HlTag::Operator(HlOperator::Other) | HlMod::ControlFlow,
             IDENT if parent_matches::<ast::TokenTree>(&token) => {
                 if let Some(attr) = token.ancestors().nth(2).and_then(ast::Attr::cast) {
-                    match try_resolve_derive_input_at(sema, &attr, &token) {
-                        Some(makro) => highlight_def(sema, krate, Definition::Macro(makro)),
+                    match try_resolve_derive_input(sema, &attr, &ast::Ident::cast(token).unwrap()) {
+                        Some(res) => highlight_def(sema, krate, Definition::from(res)),
                         None => HlTag::None.into(),
                     }
                 } else {

crates/ide/src/syntax_highlighting/test_data/highlighting.html

@@ -43,15 +43,6 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 <pre><code><span class="keyword">use</span> <span class="module">inner</span><span class="operator">::</span><span class="brace">{</span><span class="self_keyword">self</span> <span class="keyword">as</span> <span class="module declaration">inner_mod</span><span class="brace">}</span><span class="semicolon">;</span>
 <span class="keyword">mod</span> <span class="module declaration">inner</span> <span class="brace">{</span><span class="brace">}</span>
 
-<span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="builtin_attr attribute">rustc_builtin_macro</span><span class="attribute attribute">]</span>
-<span class="keyword">macro</span> <span class="macro declaration">Copy</span> <span class="brace">{</span><span class="brace">}</span>
-
-<span class="comment">// Needed for function consuming vs normal</span>
-<span class="keyword">pub</span> <span class="keyword">mod</span> <span class="module declaration public">marker</span> <span class="brace">{</span>
-    <span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="builtin_attr attribute">lang</span><span class="attribute attribute"> </span><span class="operator attribute">=</span><span class="attribute attribute"> </span><span class="string_literal attribute">"copy"</span><span class="attribute attribute">]</span>
-    <span class="keyword">pub</span> <span class="keyword">trait</span> <span class="trait declaration public">Copy</span> <span class="brace">{</span><span class="brace">}</span>
-<span class="brace">}</span>
-
 <span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="module attribute">proc_macros</span><span class="operator attribute">::</span><span class="builtin_attr attribute">identity</span><span class="attribute attribute">]</span>
 <span class="keyword">pub</span> <span class="keyword">mod</span> <span class="module declaration public">ops</span> <span class="brace">{</span>
     <span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="builtin_attr attribute">lang</span> <span class="operator attribute">=</span> <span class="string_literal attribute">"fn_once"</span><span class="attribute attribute">]</span>
@@ -95,7 +86,7 @@ proc_macros::<span class="macro">mirror!</span> <span class="brace">{</span>
     <span class="brace">}</span>
 <span class="brace">}</span>
 
-<span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="builtin_attr attribute">derive</span><span class="parenthesis attribute">(</span><span class="macro attribute">Copy</span><span class="parenthesis attribute">)</span><span class="attribute attribute">]</span>
+<span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="macro attribute">derive</span><span class="parenthesis attribute">(</span><span class="macro attribute default_library library">Copy</span><span class="parenthesis attribute">)</span><span class="attribute attribute">]</span>
 <span class="keyword">struct</span> <span class="struct declaration">FooCopy</span> <span class="brace">{</span>
     <span class="field declaration">x</span><span class="colon">:</span> <span class="builtin_type">u32</span><span class="comma">,</span>
 <span class="brace">}</span>
@@ -135,7 +126,7 @@ proc_macros::<span class="macro">mirror!</span> <span class="brace">{</span>
     <span class="value_param callable">f</span><span class="parenthesis">(</span><span class="parenthesis">)</span>
 <span class="brace">}</span>
 
-<span class="keyword">fn</span> <span class="function declaration">foobar</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="operator">-&gt;</span> <span class="keyword">impl</span> <span class="macro">Copy</span> <span class="brace">{</span><span class="brace">}</span>
+<span class="keyword">fn</span> <span class="function declaration">foobar</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="operator">-&gt;</span> <span class="keyword">impl</span> <span class="trait default_library library">Copy</span> <span class="brace">{</span><span class="brace">}</span>
 
 <span class="keyword">fn</span> <span class="function declaration">foo</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="brace">{</span>
     <span class="keyword">let</span> <span class="variable declaration">bar</span> <span class="operator">=</span> <span class="function">foobar</span><span class="parenthesis">(</span><span class="parenthesis">)</span><span class="semicolon">;</span>

crates/ide/src/syntax_highlighting/tests.rs

@@ -11,19 +11,11 @@ fn test_highlighting() {
     check_highlighting(
         r#"
 //- proc_macros: identity, mirror
+//- minicore: derive, copy
 //- /main.rs crate:main deps:foo
 use inner::{self as inner_mod};
 mod inner {}
 
-#[rustc_builtin_macro]
-macro Copy {}
-
-// Needed for function consuming vs normal
-pub mod marker {
-    #[lang = "copy"]
-    pub trait Copy {}
-}
-
 #[proc_macros::identity]
 pub mod ops {
     #[lang = "fn_once"]

crates/ide_assists/src/handlers/auto_import.rs

@@ -3,7 +3,7 @@ use ide_db::helpers::{
     insert_use::{insert_use, ImportScope},
     mod_path_to_ast,
 };
-use syntax::{ast, AstNode, SyntaxNode};
+use syntax::{ast, AstNode, AstToken, SyntaxNode};
 
 use crate::{AssistContext, AssistId, AssistKind, Assists, GroupLabel};
 
@@ -128,9 +128,10 @@ pub(super) fn find_importable_node(ctx: &AssistContext) -> Option<(ImportAssets,
         .find_node_at_offset_with_descend::<ast::IdentPat>()
         .filter(ast::IdentPat::is_simple_ident)
     {
-        ImportAssets::for_ident_pat(&pat, &ctx.sema).zip(Some(pat.syntax().clone()))
+        ImportAssets::for_ident_pat(&ctx.sema, &pat).zip(Some(pat.syntax().clone()))
     } else {
-        None
+        let ident = ctx.find_token_at_offset()?;
+        ImportAssets::for_derive_ident(&ctx.sema, &ident).zip(ident.syntax().parent())
     }
 }
 

crates/ide_db/src/defs.rs

@@ -12,10 +12,10 @@ use hir::{
 };
 use syntax::{
     ast::{self, AstNode},
-    match_ast, SyntaxKind, SyntaxNode, SyntaxToken,
+    match_ast, AstToken, SyntaxKind, SyntaxNode, SyntaxToken,
 };
 
-use crate::{helpers::try_resolve_derive_input_at, RootDatabase};
+use crate::{helpers::try_resolve_derive_input, RootDatabase};
 
 // FIXME: a more precise name would probably be `Symbol`?
 #[derive(Debug, PartialEq, Eq, Copy, Clone, Hash)]
@@ -38,19 +38,20 @@ impl Definition {
             Some(parent) => parent,
             None => return Default::default(),
         };
-        let attr = parent
-            .ancestors()
-            .find_map(ast::TokenTree::cast)
-            .and_then(|tt| tt.parent_meta())
-            .and_then(|meta| meta.parent_attr());
-        if let Some(attr) = attr {
-            try_resolve_derive_input_at(&sema, &attr, &token)
-                .map(Definition::Macro)
-                .into_iter()
-                .collect()
-        } else {
-            Self::from_node(sema, &parent)
+        if let Some(ident) = ast::Ident::cast(token.clone()) {
+            let attr = parent
+                .ancestors()
+                .find_map(ast::TokenTree::cast)
+                .and_then(|tt| tt.parent_meta())
+                .and_then(|meta| meta.parent_attr());
+            if let Some(attr) = attr {
+                return try_resolve_derive_input(&sema, &attr, &ident)
+                    .map(Into::into)
+                    .into_iter()
+                    .collect();
+            }
         }
+        Self::from_node(sema, &parent)
     }
 
     pub fn from_node(sema: &Semantics<RootDatabase>, node: &SyntaxNode) -> ArrayVec<Definition, 2> {

crates/ide_db/src/helpers.rs

@@ -7,14 +7,16 @@ pub mod merge_imports;
 pub mod node_ext;
 pub mod rust_doc;
 
-use std::collections::VecDeque;
+use std::{collections::VecDeque, iter};
 
 use base_db::FileId;
 use either::Either;
-use hir::{ItemInNs, MacroDef, ModuleDef, Name, Semantics};
+use hir::{ItemInNs, MacroDef, ModuleDef, Name, PathResolution, Semantics};
+use itertools::Itertools;
 use syntax::{
-    ast::{self, make, HasLoopBody},
-    AstNode, Direction, SyntaxElement, SyntaxKind, SyntaxToken, TokenAtOffset, WalkEvent, T,
+    ast::{self, make, HasLoopBody, Ident},
+    AstNode, AstToken, Direction, SyntaxElement, SyntaxKind, SyntaxToken, TokenAtOffset, WalkEvent,
+    T,
 };
 
 use crate::RootDatabase;
@@ -29,33 +31,59 @@ pub fn item_name(db: &RootDatabase, item: ItemInNs) -> Option<Name> {
     }
 }
 
-/// Resolves the path at the cursor token as a derive macro if it inside a token tree of a derive attribute.
-pub fn try_resolve_derive_input_at(
+/// Parses and returns the derive path at the cursor position in the given attribute, if it is a derive.
+/// This special case is required because the derive macro is a compiler builtin that discards the input derives.
+///
+/// The returned path is synthesized from TokenTree tokens and as such cannot be used with the [`Semantics`].
+pub fn get_path_in_derive_attr(
     sema: &hir::Semantics<RootDatabase>,
-    derive_attr: &ast::Attr,
-    cursor: &SyntaxToken,
-) -> Option<MacroDef> {
-    use itertools::Itertools;
-    if cursor.kind() != T![ident] {
+    attr: &ast::Attr,
+    cursor: &Ident,
+) -> Option<ast::Path> {
+    let cursor = cursor.syntax();
+    let path = attr.path()?;
+    let tt = attr.token_tree()?;
+    if !tt.syntax().text_range().contains_range(cursor.text_range()) {
         return None;
     }
-    let tt = match derive_attr.as_simple_call() {
-        Some((name, tt))
-            if name == "derive" && tt.syntax().text_range().contains_range(cursor.text_range()) =>
-        {
-            tt
-        }
-        _ => return None,
-    };
-    let tokens: Vec<_> = cursor
+    let scope = sema.scope(attr.syntax());
+    let resolved_attr = sema.resolve_path(&path)?;
+    let derive = FamousDefs(sema, scope.krate()).core_macros_builtin_derive()?;
+    if PathResolution::Macro(derive) != resolved_attr {
+        return None;
+    }
+
+    let first = cursor
         .siblings_with_tokens(Direction::Prev)
-        .flat_map(SyntaxElement::into_token)
+        .filter_map(SyntaxElement::into_token)
         .take_while(|tok| tok.kind() != T!['('] && tok.kind() != T![,])
-        .collect();
-    let path = ast::Path::parse(&tokens.into_iter().rev().join("")).ok()?;
-    sema.scope(tt.syntax())
-        .speculative_resolve_as_mac(&path)
-        .filter(|mac| mac.kind() == hir::MacroKind::Derive)
+        .last()?;
+    let path_tokens = first
+        .siblings_with_tokens(Direction::Next)
+        .filter_map(SyntaxElement::into_token)
+        .take_while(|tok| tok != cursor);
+
+    ast::Path::parse(&path_tokens.chain(iter::once(cursor.clone())).join("")).ok()
+}
+
+/// Parses and resolves the path at the cursor position in the given attribute, if it is a derive.
+/// This special case is required because the derive macro is a compiler builtin that discards the input derives.
+pub fn try_resolve_derive_input(
+    sema: &hir::Semantics<RootDatabase>,
+    attr: &ast::Attr,
+    cursor: &Ident,
+) -> Option<PathResolution> {
+    let path = get_path_in_derive_attr(sema, attr, cursor)?;
+    let scope = sema.scope(attr.syntax());
+    // FIXME: This double resolve shouldn't be necessary
+    // It's only here so we prefer macros over other namespaces
+    match scope.speculative_resolve_as_mac(&path) {
+        Some(mac) if mac.kind() == hir::MacroKind::Derive => Some(PathResolution::Macro(mac)),
+        Some(_) => return None,
+        None => scope
+            .speculative_resolve(&path)
+            .filter(|res| matches!(res, PathResolution::Def(ModuleDef::Module(_)))),
+    }
 }
 
 /// Picks the token with the highest rank returned by the passed in function.

crates/ide_db/src/helpers/famous_defs.rs

@@ -1,5 +1,5 @@
 //! See [`FamousDefs`].
-use hir::{Crate, Enum, Module, ScopeDef, Semantics, Trait};
+use hir::{Crate, Enum, MacroDef, Module, ScopeDef, Semantics, Trait};
 
 use crate::RootDatabase;
 
@@ -80,6 +80,10 @@ impl FamousDefs<'_, '_> {
         self.find_trait("core:marker:Copy")
     }
 
+    pub fn core_macros_builtin_derive(&self) -> Option<MacroDef> {
+        self.find_macro("core:macros:builtin:derive")
+    }
+
     pub fn alloc(&self) -> Option<Crate> {
         self.find_crate("alloc")
     }
@@ -110,6 +114,13 @@ impl FamousDefs<'_, '_> {
         }
     }
 
+    fn find_macro(&self, path: &str) -> Option<MacroDef> {
+        match self.find_def(path)? {
+            hir::ScopeDef::MacroDef(it) => Some(it),
+            _ => None,
+        }
+    }
+
     fn find_enum(&self, path: &str) -> Option<Enum> {
         match self.find_def(path)? {
             hir::ScopeDef::ModuleDef(hir::ModuleDef::Adt(hir::Adt::Enum(it))) => Some(it),

crates/ide_db/src/helpers/import_assets.rs

@@ -8,10 +8,11 @@ use rustc_hash::FxHashSet;
 use syntax::{
     ast::{self, HasName},
     utils::path_to_string_stripping_turbo_fish,
-    AstNode, SyntaxNode,
+    AstNode, AstToken, SyntaxNode,
 };
 
 use crate::{
+    helpers::get_path_in_derive_attr,
     items_locator::{self, AssocItemSearch, DEFAULT_QUERY_SEARCH_LIMIT},
     RootDatabase,
 };
@@ -119,7 +120,7 @@ impl ImportAssets {
         })
     }
 
-    pub fn for_ident_pat(pat: &ast::IdentPat, sema: &Semantics<RootDatabase>) -> Option<Self> {
+    pub fn for_ident_pat(sema: &Semantics<RootDatabase>, pat: &ast::IdentPat) -> Option<Self> {
         if !pat.is_simple_ident() {
             return None;
         }
@@ -132,6 +133,22 @@ impl ImportAssets {
         })
     }
 
+    pub fn for_derive_ident(sema: &Semantics<RootDatabase>, ident: &ast::Ident) -> Option<Self> {
+        let attr = ident.syntax().ancestors().find_map(ast::Attr::cast)?;
+        let path = get_path_in_derive_attr(sema, &attr, ident)?;
+
+        if let Some(_) = path.qualifier() {
+            return None;
+        }
+        let name = NameToImport::Exact(path.segment()?.name_ref()?.to_string());
+        let candidate_node = attr.syntax().clone();
+        Some(Self {
+            import_candidate: ImportCandidate::Path(PathImportCandidate { qualifier: None, name }),
+            module_with_candidate: sema.scope(&candidate_node).module()?,
+            candidate_node,
+        })
+    }
+
     pub fn for_fuzzy_path(
         module_with_candidate: Module,
         qualifier: Option<ast::Path>,

crates/rust-analyzer/src/to_proto.rs

@@ -673,7 +673,7 @@ pub(crate) fn location(
     Ok(loc)
 }
 
-/// Perefer using `location_link`, if the client has the cap.
+/// Prefer using `location_link`, if the client has the cap.
 pub(crate) fn location_from_nav(
     snap: &GlobalStateSnapshot,
     nav: NavigationTarget,

crates/syntax/src/ast/generated/tokens.rs

@@ -131,3 +131,24 @@ impl AstToken for FloatNumber {
     }
     fn syntax(&self) -> &SyntaxToken { &self.syntax }
 }
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Ident {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for Ident {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for Ident {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == IDENT }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}

crates/syntax/src/tests/sourcegen_ast.rs

@@ -560,7 +560,7 @@ impl Field {
 
 fn lower(grammar: &Grammar) -> AstSrc {
     let mut res = AstSrc {
-        tokens: "Whitespace Comment String ByteString IntNumber FloatNumber"
+        tokens: "Whitespace Comment String ByteString IntNumber FloatNumber Ident"
             .split_ascii_whitespace()
             .map(|it| it.to_string())
             .collect::<Vec<_>>(),