3 files changed, 57 insertions, 11 deletions

diff --git a/crates/ra_analysis/src/completion/mod.rs b/crates/ra_analysis/src/completion.rs
index 0f154112a..0f154112a 100644
--- a/crates/ra_analysis/src/completion/mod.rs
+++ b/crates/ra_analysis/src/completion.rs
diff --git a/crates/ra_analysis/src/imp.rs b/crates/ra_analysis/src/imp.rs
index 975afc145..03d17de0d 100644
--- a/crates/ra_analysis/src/imp.rs
+++ b/crates/ra_analysis/src/imp.rs
@@ -27,6 +27,7 @@ use crate::{
     symbol_index::{SymbolIndex, SymbolsDatabase},
     AnalysisChange, Cancelable, CrateId, Diagnostic, FileId,
     FileSystemEdit, FilePosition, Query, SourceChange, SourceFileNodeEdit,
+    ReferenceResolution,
 };
 
 #[derive(Debug, Default)]
@@ -144,7 +145,7 @@ 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 +165,7 @@ 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)? {
@@ -206,10 +207,11 @@ impl AnalysisImpl {
     pub fn approximately_resolve_symbol(
         &self,
         position: FilePosition,
-    ) -> Cancelable<Vec<(FileId, FileSymbol)>> {
+    ) -> Cancelable<Option<ReferenceResolution>> {
         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) {
+            let mut rr = ReferenceResolution::new(name_ref.syntax().range());
             if let Some(fn_descr) = source_binder::function_from_child_node(
                 &*self.db,
                 position.file_id,
@@ -218,22 +220,25 @@ 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((
+                    rr.add_resolution(
                         position.file_id,
                         FileSymbol {
                             name: entry.name().clone(),
                             node_range: entry.ptr().range(),
                             kind: NAME,
                         },
-                    ));
-                    return Ok(vec);
+                    );
+                    return Ok(Some(rr));
                 };
             }
             // If that fails try the index based approach.
-            return self.index_resolve(name_ref);
+            for (file_id, symbol) in self.index_resolve(name_ref)? {
+                rr.add_resolution(file_id, symbol);
+            }
+            return Ok(Some(rr));
         }
         if let Some(name) = find_node_at_offset::<ast::Name>(syntax, position.offset) {
+            let mut rr = ReferenceResolution::new(name.syntax().range());
             if let Some(module) = name.syntax().parent().and_then(ast::Module::cast) {
                 if module.has_semi() {
                     let parent_module =
@@ -248,7 +253,8 @@ impl AnalysisImpl {
                                     node_range: TextRange::offset_len(0.into(), 0.into()),
                                     kind: MODULE,
                                 };
-                                return Ok(vec![(file_id, symbol)]);
+                                rr.add_resolution(file_id, symbol);
+                                return Ok(Some(rr));
                             }
                         }
                         _ => (),
@@ -256,7 +262,7 @@ impl AnalysisImpl {
                 }
             }
         }
-        Ok(vec![])
+        Ok(None)
     }
 
     pub fn find_all_refs(&self, position: FilePosition) -> Cancelable<Vec<(FileId, TextRange)>> {
@@ -318,6 +324,19 @@ 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..eaf24cb36 100644
--- a/crates/ra_analysis/src/lib.rs
+++ b/crates/ra_analysis/src/lib.rs
@@ -178,6 +178,30 @@ impl Query {
     }
 }
 
+/// Result of "goto def" query.
+#[derive(Debug)]
+pub struct ReferenceResolution {
+    /// The range of the reference itself. Client does not know what constitutes
+    /// a reference, it handles us only the offset. It's helpful to tell the
+    /// client where the reference was.
+    pub reference_range: TextRange,
+    /// What this reference resolves to.
+    pub resolves_to: Vec<(FileId, FileSymbol)>,
+}
+
+impl ReferenceResolution {
+    fn new(reference_range: TextRange) -> ReferenceResolution {
+        ReferenceResolution {
+            reference_range,
+            resolves_to: Vec::new(),
+        }
+    }
+
+    fn add_resolution(&mut self, file_id: FileId, symbol: FileSymbol) {
+        self.resolves_to.push((file_id, symbol))
+    }
+}
+
 /// Analysis is a snapshot of a world state at a moment in time. It is the main
 /// entry point for asking semantic information about the world. When the world
 /// state is advanced using `AnalysisHost::apply_change` method, all existing
@@ -236,7 +260,7 @@ impl Analysis {
     pub fn approximately_resolve_symbol(
         &self,
         position: FilePosition,
-    ) -> Cancelable<Vec<(FileId, FileSymbol)>> {
+    ) -> Cancelable<Option<ReferenceResolution>> {
         self.imp.approximately_resolve_symbol(position)
     }
     pub fn find_all_refs(&self, position: FilePosition) -> Cancelable<Vec<(FileId, TextRange)>> {
@@ -249,6 +273,9 @@ 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)
     }