Merge #1208

1208: [WIP] Goto for Macro's r=matklad a=Lapz

Adds goto definition for macros. Currently only works for macros in the current crate ~~otherwise it panics~~. Proper macro resolution needs to be added for it to resolve macros in other crates.

Todo
- [X] Allow goto from macro calls
- [X] Fix panics
- [x] Add tests



![Screen Recording 2019-04-25 at 18 00 24](https://user-images.githubusercontent.com/19998186/56754499-1dd01c00-6785-11e9-9e9a-1e36de70cfa3.gif)



Co-authored-by: Lenard Pratt <l3np27@gmail.com>

crates/ra_hir/src/lib.rs

@@ -69,7 +69,7 @@ pub use self::{
     expr::ExprScopes,
     resolve::Resolution,
     generics::{GenericParams, GenericParam, HasGenericParams},
-    source_binder::{SourceAnalyzer, PathResolution, ScopeEntryWithSyntax},
+    source_binder::{SourceAnalyzer, PathResolution, ScopeEntryWithSyntax,MacroByExampleDef},
 };
 
 pub use self::code_model_api::{
@@ -80,5 +80,5 @@ pub use self::code_model_api::{
     Function, FnSignature,
     StructField, FieldSource,
     Static, Const, ConstSignature,
-    Trait, TypeAlias, Container,
+    Trait, TypeAlias, Container
 };

crates/ra_hir/src/source_binder.rs

@@ -10,7 +10,7 @@ use std::sync::Arc;
 use rustc_hash::{FxHashSet, FxHashMap};
 use ra_db::{FileId, FilePosition};
 use ra_syntax::{
-    SyntaxNode, AstPtr, TextUnit, SyntaxNodePtr, TextRange,
+    SyntaxNode, AstPtr, TextUnit, SyntaxNodePtr, TextRange,TreeArc,
     ast::{self, AstNode, NameOwner},
     algo::find_node_at_offset,
     SyntaxKind::*,
@@ -18,9 +18,10 @@ use ra_syntax::{
 
 use crate::{
     HirDatabase, Function, Struct, Enum, Const, Static, Either, DefWithBody, PerNs, Name,
-    AsName, Module, HirFileId, Crate, Trait, Resolver, Ty,
+    AsName, Module, HirFileId, Crate, Trait, Resolver, Ty,Path,
     expr::{BodySourceMap, scope::{ScopeId, ExprScopes}},
-    ids::LocationCtx,
+    ids::{LocationCtx,MacroCallId},
+    docs::{docs_from_ast,Documentation},
     expr, AstId,
 };
 
@@ -184,9 +185,28 @@ pub enum PathResolution {
     /// A generic parameter
     GenericParam(u32),
     SelfType(crate::ImplBlock),
+    Macro(MacroByExampleDef),
     AssocItem(crate::ImplItem),
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct MacroByExampleDef {
+    pub(crate) id: MacroCallId,
+}
+
+impl MacroByExampleDef {
+    pub fn source(&self, db: &impl HirDatabase) -> (HirFileId, TreeArc<ast::MacroCall>) {
+        let loc = self.id.loc(db);
+        (self.id.into(), loc.def.0.to_node(db))
+    }
+}
+
+impl crate::Docs for MacroByExampleDef {
+    fn docs(&self, db: &impl HirDatabase) -> Option<Documentation> {
+        docs_from_ast(&*self.source(db).1)
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct ScopeEntryWithSyntax {
     pub(crate) name: Name,
@@ -264,6 +284,23 @@ impl SourceAnalyzer {
         self.infer.as_ref()?.field_resolution(expr_id)
     }
 
+    pub fn resolve_macro_call(
+        &self,
+        db: &impl HirDatabase,
+        file_id: FileId,
+        macro_call: &ast::MacroCall,
+    ) -> Option<MacroByExampleDef> {
+        let hir_id = file_id.into();
+        let ast_id = db.ast_id_map(hir_id).ast_id(macro_call).with_file_id(hir_id);
+        let call_id = self.resolver.resolve_macro_call(
+            db,
+            macro_call.path().and_then(Path::from_ast),
+            ast_id,
+        );
+
+        call_id.map(|id| MacroByExampleDef { id })
+    }
+
     pub fn resolve_hir_path(
         &self,
         db: &impl HirDatabase,

crates/ra_ide_api/src/completion/completion_item.rs

@@ -89,6 +89,7 @@ pub enum CompletionItemKind {
     TypeAlias,
     Method,
     TypeParam,
+    Macro,
 }
 
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]

crates/ra_ide_api/src/display/navigation_target.rs

@@ -213,6 +213,15 @@ impl NavigationTarget {
         }
     }
 
+    pub(crate) fn from_macro_def(
+        db: &RootDatabase,
+        macro_call: hir::MacroByExampleDef,
+    ) -> NavigationTarget {
+        let (file_id, node) = macro_call.source(db);
+        log::debug!("nav target {}", node.syntax().debug_dump());
+        NavigationTarget::from_named(file_id.original_file(db), &*node)
+    }
+
     #[cfg(test)]
     pub(crate) fn assert_match(&self, expected: &str) {
         let actual = self.debug_render();
@@ -289,6 +298,7 @@ impl NavigationTarget {
             .visit(doc_comments::<ast::StaticDef>)
             .visit(doc_comments::<ast::NamedFieldDef>)
             .visit(doc_comments::<ast::EnumVariant>)
+            .visit(doc_comments::<ast::MacroCall>)
             .accept(&node)?
     }
 

crates/ra_ide_api/src/goto_definition.rs

@@ -59,6 +59,21 @@ pub(crate) fn reference_definition(
             return Exact(NavigationTarget::from_function(db, func));
         }
     }
+
+    //it could be a macro call
+    if let Some(macro_call) = name_ref
+        .syntax()
+        .parent()
+        .and_then(|node| node.parent())
+        .and_then(|node| node.parent())
+        .and_then(ast::MacroCall::cast)
+    {
+        tested_by!(goto_definition_works_for_macros);
+        if let Some(macro_call) = analyzer.resolve_macro_call(db, file_id, macro_call) {
+            return Exact(NavigationTarget::from_macro_def(db, macro_call));
+        }
+    }
+
     // It could also be a field access
     if let Some(field_expr) = name_ref.syntax().parent().and_then(ast::FieldExpr::cast) {
         tested_by!(goto_definition_works_for_fields);
@@ -97,6 +112,10 @@ pub(crate) fn reference_definition(
                 hir::PathResolution::GenericParam(..) => {
                     // FIXME: go to the generic param def
                 }
+                hir::PathResolution::Macro(def) => {
+                    let nav = NavigationTarget::from_macro_def(db, def);
+                    return Exact(nav);
+                }
                 hir::PathResolution::SelfType(impl_block) => {
                     let ty = impl_block.target_ty(db);
 
@@ -156,6 +175,7 @@ fn named_target(file_id: FileId, node: &SyntaxNode) -> Option<NavigationTarget>
         .visit(|node: &ast::TraitDef| NavigationTarget::from_named(file_id, node))
         .visit(|node: &ast::NamedFieldDef| NavigationTarget::from_named(file_id, node))
         .visit(|node: &ast::Module| NavigationTarget::from_named(file_id, node))
+        .visit(|node: &ast::MacroCall| NavigationTarget::from_named(file_id, node))
         .accept(node)
 }
 
@@ -227,6 +247,26 @@ mod tests {
         );
     }
 
+    #[test]
+    fn goto_definition_works_for_macros() {
+        covers!(goto_definition_works_for_macros);
+        check_goto(
+            "
+            //- /lib.rs
+            macro_rules! foo {
+                () => {
+                    {}
+                };
+            }
+
+            fn bar() {
+                <|>foo!();
+            }
+            ",
+            "foo MACRO_CALL FileId(1) [0; 50) [13; 16)",
+        );
+    }
+
     #[test]
     fn goto_definition_works_for_methods() {
         covers!(goto_definition_works_for_methods);

crates/ra_ide_api/src/marks.rs

@@ -1,5 +1,6 @@
 test_utils::marks!(
     inserts_parens_for_function_calls
+    goto_definition_works_for_macros
     goto_definition_works_for_methods
     goto_definition_works_for_fields
     goto_definition_works_for_named_fields

crates/ra_lsp_server/src/conv.rs

@@ -73,6 +73,7 @@ impl Conv for CompletionItemKind {
             CompletionItemKind::Static => Value,
             CompletionItemKind::Method => Method,
             CompletionItemKind::TypeParam => TypeParameter,
+            CompletionItemKind::Macro => Method,
         }
     }
 }

crates/ra_syntax/src/ast/generated.rs

@@ -1761,6 +1761,7 @@ impl ToOwned for MacroCall {
 
 impl ast::NameOwner for MacroCall {}
 impl ast::AttrsOwner for MacroCall {}
+impl ast::DocCommentsOwner for MacroCall {}
 impl MacroCall {
     pub fn token_tree(&self) -> Option<&TokenTree> {
         super::child_opt(self)

crates/ra_syntax/src/grammar.ron

@@ -552,7 +552,7 @@ Grammar(
         "Name": (),
         "NameRef": (),
         "MacroCall": (
-            traits: [ "NameOwner", "AttrsOwner" ],
+            traits: [ "NameOwner", "AttrsOwner","DocCommentsOwner" ],
             options: [ "TokenTree", "Path" ],
         ),
         "Attr": ( options: [ ["value", "TokenTree"] ] ),