8 files changed, 116 insertions, 35 deletions

diff --git a/crates/ra_analysis/src/imp.rs b/crates/ra_analysis/src/imp.rs
index 975afc145..99bcf0666 100644
--- a/crates/ra_analysis/src/imp.rs
+++ b/crates/ra_analysis/src/imp.rs
@@ -144,7 +144,7 @@ impl AnalysisImpl {
         } else {
             let files = &self.db.source_root(WORKSPACE).files;
 
-            /// Need to wrap Snapshot to provide `Clon` impl for `map_with`
+            /// Need to wrap Snapshot to provide `Clone` impl for `map_with`
             struct Snap(salsa::Snapshot<db::RootDatabase>);
             impl Clone for Snap {
                 fn clone(&self) -> Snap {
@@ -164,7 +164,7 @@ impl AnalysisImpl {
             .sweep(salsa::SweepStrategy::default().discard_values());
         Ok(query.search(&buf))
     }
-    /// This return `Vec`: a module may be included from several places. We
+    /// This returns `Vec` because a module may be included from several places. We
     /// don't handle this case yet though, so the Vec has length at most one.
     pub fn parent_module(&self, position: FilePosition) -> Cancelable<Vec<(FileId, FileSymbol)>> {
         let descr = match source_binder::module_from_position(&*self.db, position)? {
@@ -206,7 +206,7 @@ impl AnalysisImpl {
     pub fn approximately_resolve_symbol(
         &self,
         position: FilePosition,
-    ) -> Cancelable<Vec<(FileId, FileSymbol)>> {
+    ) -> Cancelable<Option<(TextRange, Vec<(FileId, FileSymbol)>)>> {
         let file = self.db.source_file(position.file_id);
         let syntax = file.syntax();
         if let Some(name_ref) = find_node_at_offset::<ast::NameRef>(syntax, position.offset) {
@@ -218,20 +218,22 @@ impl AnalysisImpl {
                 let scope = fn_descr.scope(&*self.db);
                 // First try to resolve the symbol locally
                 if let Some(entry) = scope.resolve_local_name(name_ref) {
-                    let mut vec = vec![];
-                    vec.push((
+                    let vec = vec![(
                         position.file_id,
                         FileSymbol {
                             name: entry.name().clone(),
                             node_range: entry.ptr().range(),
                             kind: NAME,
                         },
-                    ));
-                    return Ok(vec);
+                    )];
+                    return Ok(Some((name_ref.syntax().range(), vec)));
                 };
             }
             // If that fails try the index based approach.
-            return self.index_resolve(name_ref);
+            return Ok(Some((
+                name_ref.syntax().range(),
+                self.index_resolve(name_ref)?,
+            )));
         }
         if let Some(name) = find_node_at_offset::<ast::Name>(syntax, position.offset) {
             if let Some(module) = name.syntax().parent().and_then(ast::Module::cast) {
@@ -248,7 +250,7 @@ impl AnalysisImpl {
                                     node_range: TextRange::offset_len(0.into(), 0.into()),
                                     kind: MODULE,
                                 };
-                                return Ok(vec![(file_id, symbol)]);
+                                return Ok(Some((name.syntax().range(), vec![(file_id, symbol)])));
                             }
                         }
                         _ => (),
@@ -256,7 +258,10 @@ impl AnalysisImpl {
                 }
             }
         }
-        Ok(vec![])
+        let range =
+            ctry!(ra_syntax::algo::find_leaf_at_offset(syntax, position.offset).left_biased())
+                .range();
+        Ok(Some((range, vec![])))
     }
 
     pub fn find_all_refs(&self, position: FilePosition) -> Cancelable<Vec<(FileId, TextRange)>> {
@@ -318,6 +323,19 @@ impl AnalysisImpl {
 
         Ok(symbol.docs(&file))
     }
+    pub fn doc_text_for(&self, file_id: FileId, symbol: FileSymbol) -> Cancelable<Option<String>> {
+        let file = self.db.source_file(file_id);
+        let result = match (symbol.description(&file), symbol.docs(&file)) {
+            (Some(desc), Some(docs)) => {
+                Some("```rust\n".to_string() + &*desc + "\n```\n\n" + &*docs)
+            }
+            (Some(desc), None) => Some("```rust\n".to_string() + &*desc + "\n```"),
+            (None, Some(docs)) => Some(docs),
+            _ => None,
+        };
+
+        Ok(result)
+    }
 
     pub fn diagnostics(&self, file_id: FileId) -> Cancelable<Vec<Diagnostic>> {
         let syntax = self.db.source_file(file_id);
diff --git a/crates/ra_analysis/src/lib.rs b/crates/ra_analysis/src/lib.rs
index 4b8b10816..d33f3e4ca 100644
--- a/crates/ra_analysis/src/lib.rs
+++ b/crates/ra_analysis/src/lib.rs
@@ -236,7 +236,7 @@ impl Analysis {
     pub fn approximately_resolve_symbol(
         &self,
         position: FilePosition,
-    ) -> Cancelable<Vec<(FileId, FileSymbol)>> {
+    ) -> Cancelable<Option<(TextRange, Vec<(FileId, FileSymbol)>)>> {
         self.imp.approximately_resolve_symbol(position)
     }
     pub fn find_all_refs(&self, position: FilePosition) -> Cancelable<Vec<(FileId, TextRange)>> {
@@ -249,6 +249,9 @@ impl Analysis {
     ) -> Cancelable<Option<String>> {
         self.imp.doc_comment_for(file_id, symbol)
     }
+    pub fn doc_text_for(&self, file_id: FileId, symbol: FileSymbol) -> Cancelable<Option<String>> {
+        self.imp.doc_text_for(file_id, symbol)
+    }
     pub fn parent_module(&self, position: FilePosition) -> Cancelable<Vec<(FileId, FileSymbol)>> {
         self.imp.parent_module(position)
     }
diff --git a/crates/ra_analysis/tests/tests.rs b/crates/ra_analysis/tests/tests.rs
index 4ce2c5c85..05ad687ae 100644
--- a/crates/ra_analysis/tests/tests.rs
+++ b/crates/ra_analysis/tests/tests.rs
@@ -21,9 +21,9 @@ fn approximate_resolve_works_in_items() {
     ",
     );
 
-    let symbols = analysis.approximately_resolve_symbol(pos).unwrap();
+    let symbols = analysis.approximately_resolve_symbol(pos).unwrap().unwrap();
     assert_eq_dbg(
-        r#"[(FileId(1), FileSymbol { name: "Foo", node_range: [0; 11), kind: STRUCT_DEF })]"#,
+        r#"([23; 26), [(FileId(1), FileSymbol { name: "Foo", node_range: [0; 11), kind: STRUCT_DEF })])"#,
         &symbols,
     );
 }
@@ -39,9 +39,9 @@ fn test_resolve_module() {
     ",
     );
 
-    let symbols = analysis.approximately_resolve_symbol(pos).unwrap();
+    let symbols = analysis.approximately_resolve_symbol(pos).unwrap().unwrap();
     assert_eq_dbg(
-        r#"[(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]"#,
+        r#"([4; 7), [(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })])"#,
         &symbols,
     );
 
@@ -54,9 +54,9 @@ fn test_resolve_module() {
     ",
     );
 
-    let symbols = analysis.approximately_resolve_symbol(pos).unwrap();
+    let symbols = analysis.approximately_resolve_symbol(pos).unwrap().unwrap();
     assert_eq_dbg(
-        r#"[(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]"#,
+        r#"([4; 7), [(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })])"#,
         &symbols,
     );
 }
diff --git a/crates/ra_editor/src/symbols.rs b/crates/ra_editor/src/symbols.rs
index 6d3b0514a..9e25decfb 100644
--- a/crates/ra_editor/src/symbols.rs
+++ b/crates/ra_editor/src/symbols.rs
@@ -50,6 +50,61 @@ impl FileSymbol {
             })
             .nth(0)
     }
+    /// Get a description of this node.
+    ///
+    /// e.g. `struct Name`, `enum Name`, `fn Name`
+    pub fn description(&self, file: &SourceFileNode) -> Option<String> {
+        // TODO: After type inference is done, add type information to improve the output
+        file.syntax()
+            .descendants()
+            .filter(|node| node.kind() == self.kind && node.range() == self.node_range)
+            .filter_map(|node: SyntaxNodeRef| {
+                // TODO: Refactor to be have less repetition
+                visitor()
+                    .visit(|node: ast::FnDef| {
+                        let mut string = "fn ".to_string();
+                        node.name()?.syntax().text().push_to(&mut string);
+                        Some(string)
+                    })
+                    .visit(|node: ast::StructDef| {
+                        let mut string = "struct ".to_string();
+                        node.name()?.syntax().text().push_to(&mut string);
+                        Some(string)
+                    })
+                    .visit(|node: ast::EnumDef| {
+                        let mut string = "enum ".to_string();
+                        node.name()?.syntax().text().push_to(&mut string);
+                        Some(string)
+                    })
+                    .visit(|node: ast::TraitDef| {
+                        let mut string = "trait ".to_string();
+                        node.name()?.syntax().text().push_to(&mut string);
+                        Some(string)
+                    })
+                    .visit(|node: ast::Module| {
+                        let mut string = "mod ".to_string();
+                        node.name()?.syntax().text().push_to(&mut string);
+                        Some(string)
+                    })
+                    .visit(|node: ast::TypeDef| {
+                        let mut string = "type ".to_string();
+                        node.name()?.syntax().text().push_to(&mut string);
+                        Some(string)
+                    })
+                    .visit(|node: ast::ConstDef| {
+                        let mut string = "const ".to_string();
+                        node.name()?.syntax().text().push_to(&mut string);
+                        Some(string)
+                    })
+                    .visit(|node: ast::StaticDef| {
+                        let mut string = "static ".to_string();
+                        node.name()?.syntax().text().push_to(&mut string);
+                        Some(string)
+                    })
+                    .accept(node)?
+            })
+            .nth(0)
+    }
 }
 
 pub fn file_symbols(file: &SourceFileNode) -> Vec<FileSymbol> {
diff --git a/crates/ra_lsp_server/src/main_loop/handlers.rs b/crates/ra_lsp_server/src/main_loop/handlers.rs
index af21254e4..f18a1305d 100644
--- a/crates/ra_lsp_server/src/main_loop/handlers.rs
+++ b/crates/ra_lsp_server/src/main_loop/handlers.rs
@@ -204,7 +204,10 @@ pub fn handle_goto_definition(
 ) -> Result<Option<req::GotoDefinitionResponse>> {
     let position = params.try_conv_with(&world)?;
     let mut res = Vec::new();
-    for (file_id, symbol) in world.analysis().approximately_resolve_symbol(position)? {
+    for (file_id, symbol) in match world.analysis().approximately_resolve_symbol(position)? {
+        None => return Ok(None),
+        Some(it) => it.1,
+    } {
         let line_index = world.analysis().file_line_index(file_id);
         let location = to_location(file_id, symbol.node_range, &world, &line_index)?;
         res.push(location)
@@ -504,26 +507,30 @@ pub fn handle_hover(
     world: ServerWorld,
     params: req::TextDocumentPositionParams,
 ) -> Result<Option<Hover>> {
+    // TODO: Cut down on number of allocations
     let position = params.try_conv_with(&world)?;
     let line_index = world.analysis().file_line_index(position.file_id);
-
-    for (file_id, symbol) in world.analysis().approximately_resolve_symbol(position)? {
-        let range = symbol.node_range.conv_with(&line_index);
-        let comment = world.analysis.doc_comment_for(file_id, symbol)?;
-
-        if comment.is_some() {
-            let contents = HoverContents::Scalar(MarkedString::String(comment.unwrap()));
-
-            return Ok(Some(Hover {
-                contents,
-                range: Some(range),
-            }));
+    let (range, resolved) = match world.analysis().approximately_resolve_symbol(position)? {
+        None => return Ok(None),
+        Some(it) => it,
+    };
+    let mut result = Vec::new();
+    for (file_id, symbol) in resolved {
+        if let Some(docs) = world.analysis().doc_text_for(file_id, symbol)? {
+            result.push(docs);
         }
     }
-
+    let range = range.conv_with(&line_index);
+    if result.len() > 0 {
+        return Ok(Some(Hover {
+            contents: HoverContents::Scalar(MarkedString::String(result.join("\n\n---\n"))),
+            range: Some(range),
+        }));
+    }
     Ok(None)
 }
 
+/// Test doc comment
 pub fn handle_prepare_rename(
     world: ServerWorld,
     params: req::TextDocumentPositionParams,
diff --git a/crates/ra_syntax/src/grammar.ron b/crates/ra_syntax/src/grammar.ron
index 53cd2118f..eed67637e 100644
--- a/crates/ra_syntax/src/grammar.ron
+++ b/crates/ra_syntax/src/grammar.ron
@@ -25,9 +25,9 @@ Grammar(
         ["^", "CARET"],
         ["%", "PERCENT"],
     ],
-    // TODO: Confirm surmision: the tokens which cannot be recorded in a single UTF-8 byte
+    // Tokens for which the longest match must be chosen (e.g. `..` is a DOTDOT, but `.` is a DOT)
     multi_byte_tokens: [
-        [".", "DOT"], // Note: DOT is here because <TODO: REASON>
+        [".", "DOT"],
         ["..", "DOTDOT"],
         ["...", "DOTDOTDOT"],
         ["..=", "DOTDOTEQ"],
diff --git a/crates/ra_syntax/src/syntax_kinds/generated.rs b/crates/ra_syntax/src/syntax_kinds/generated.rs
index c43a8bf65..3a869ad34 100644
--- a/crates/ra_syntax/src/syntax_kinds/generated.rs
+++ b/crates/ra_syntax/src/syntax_kinds/generated.rs
@@ -560,4 +560,3 @@ impl SyntaxKind {
         Some(tok)
     }
 }
-
diff --git a/crates/ra_syntax/src/syntax_kinds/generated.rs.tera b/crates/ra_syntax/src/syntax_kinds/generated.rs.tera
index c37e57702..21f9444b1 100644
--- a/crates/ra_syntax/src/syntax_kinds/generated.rs.tera
+++ b/crates/ra_syntax/src/syntax_kinds/generated.rs.tera
@@ -75,4 +75,3 @@ impl SyntaxKind {
         Some(tok)
     }
 }
-