6 files changed, 187 insertions, 74 deletions

diff --git a/crates/ra_ide_api/src/call_info.rs b/crates/ra_ide_api/src/call_info.rs
index ee1e13799..2eb388e0e 100644
--- a/crates/ra_ide_api/src/call_info.rs
+++ b/crates/ra_ide_api/src/call_info.rs
@@ -3,9 +3,10 @@ use ra_db::SourceDatabase;
 use ra_syntax::{
     AstNode, SyntaxNode, TextUnit, TextRange,
     SyntaxKind::FN_DEF,
-    ast::{self, ArgListOwner, DocCommentsOwner},
+    ast::{self, ArgListOwner},
     algo::find_node_at_offset,
 };
+use hir::Docs;
 
 use crate::{FilePosition, CallInfo, db::RootDatabase};
 
@@ -26,7 +27,9 @@ pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<Cal
     let fn_file = db.parse(symbol.file_id);
     let fn_def = symbol.ptr.to_node(&fn_file);
     let fn_def = ast::FnDef::cast(fn_def).unwrap();
-    let mut call_info = CallInfo::new(fn_def)?;
+    let function = hir::source_binder::function_from_source(db, symbol.file_id, fn_def)?;
+
+    let mut call_info = CallInfo::new(db, function, fn_def)?;
     // If we have a calling expression let's find which argument we are on
     let num_params = call_info.parameters.len();
     let has_self = fn_def.param_list().and_then(|l| l.self_param()).is_some();
@@ -110,46 +113,13 @@ impl<'a> FnCallNode<'a> {
 }
 
 impl CallInfo {
-    fn new(node: &ast::FnDef) -> Option<Self> {
-        let label: String = if let Some(body) = node.body() {
-            let body_range = body.syntax().range();
-            let label: String = node
-                .syntax()
-                .children()
-                .filter(|child| !child.range().is_subrange(&body_range)) // Filter out body
-                .filter(|child| ast::Comment::cast(child).is_none()) // Filter out doc comments
-                .map(|node| node.text().to_string())
-                .collect();
-            label
-        } else {
-            node.syntax().text().to_string()
-        };
-
-        let mut doc = None;
-        if let Some(docs) = node.doc_comment_text() {
-            // Massage markdown
-            let mut processed_lines = Vec::new();
-            let mut in_code_block = false;
-            for line in docs.lines() {
-                if line.starts_with("```") {
-                    in_code_block = !in_code_block;
-                }
-
-                let line = if in_code_block && line.starts_with("```") && !line.contains("rust") {
-                    "```rust".into()
-                } else {
-                    line.to_string()
-                };
-
-                processed_lines.push(line);
-            }
-
-            doc = Some(processed_lines.join("\n"));
-        }
+    fn new(db: &RootDatabase, function: hir::Function, node: &ast::FnDef) -> Option<Self> {
+        let label = crate::completion::function_label(node)?;
+        let doc = function.docs(db);
 
         Some(CallInfo {
             parameters: param_list(node),
-            label: label.trim().to_owned(),
+            label,
             doc,
             active_parameter: None,
         })
@@ -284,7 +254,7 @@ fn bar() {
         assert_eq!(info.parameters, vec!["j".to_string()]);
         assert_eq!(info.active_parameter, Some(0));
         assert_eq!(info.label, "fn foo(j: u32) -> u32".to_string());
-        assert_eq!(info.doc, Some("test".into()));
+        assert_eq!(info.doc.map(|it| it.into()), Some("test".to_string()));
     }
 
     #[test]
@@ -313,18 +283,18 @@ pub fn do() {
         assert_eq!(info.active_parameter, Some(0));
         assert_eq!(info.label, "pub fn add_one(x: i32) -> i32".to_string());
         assert_eq!(
-            info.doc,
+            info.doc.map(|it| it.into()),
             Some(
                 r#"Adds one to the number given.
 
 # Examples
 
-```rust
+```
 let five = 5;
 
 assert_eq!(6, my_crate::add_one(5));
 ```"#
-                    .into()
+                    .to_string()
             )
         );
     }
@@ -359,18 +329,18 @@ pub fn do_it() {
         assert_eq!(info.active_parameter, Some(0));
         assert_eq!(info.label, "pub fn add_one(x: i32) -> i32".to_string());
         assert_eq!(
-            info.doc,
+            info.doc.map(|it| it.into()),
             Some(
                 r#"Adds one to the number given.
 
 # Examples
 
-```rust
+```
 let five = 5;
 
 assert_eq!(6, my_crate::add_one(5));
 ```"#
-                    .into()
+                    .to_string()
             )
         );
     }
@@ -414,12 +384,12 @@ pub fn foo() {
         );
         assert_eq!(info.active_parameter, Some(1));
         assert_eq!(
-            info.doc,
+            info.doc.map(|it| it.into()),
             Some(
                 r#"Method is called when writer finishes.
 
 By default this method stops actor's `Context`."#
-                    .into()
+                    .to_string()
             )
         );
     }
diff --git a/crates/ra_ide_api/src/completion.rs b/crates/ra_ide_api/src/completion.rs
index b1867de42..722d94f3a 100644
--- a/crates/ra_ide_api/src/completion.rs
+++ b/crates/ra_ide_api/src/completion.rs
@@ -10,6 +10,7 @@ mod complete_scope;
 mod complete_postfix;
 
 use ra_db::SourceDatabase;
+use ra_syntax::ast::{self, AstNode};
 
 use crate::{
     db,
@@ -61,3 +62,21 @@ pub(crate) fn completions(db: &db::RootDatabase, position: FilePosition) -> Opti
     complete_postfix::complete_postfix(&mut acc, &ctx);
     Some(acc)
 }
+
+pub fn function_label(node: &ast::FnDef) -> Option<String> {
+    let label: String = if let Some(body) = node.body() {
+        let body_range = body.syntax().range();
+        let label: String = node
+            .syntax()
+            .children()
+            .filter(|child| !child.range().is_subrange(&body_range)) // Filter out body
+            .filter(|child| ast::Comment::cast(child).is_none()) // Filter out comments
+            .map(|node| node.text().to_string())
+            .collect();
+        label
+    } else {
+        node.syntax().text().to_string()
+    };
+
+    Some(label.trim().to_owned())
+}
diff --git a/crates/ra_ide_api/src/completion/completion_item.rs b/crates/ra_ide_api/src/completion/completion_item.rs
index 49bd636a5..d3bc14894 100644
--- a/crates/ra_ide_api/src/completion/completion_item.rs
+++ b/crates/ra_ide_api/src/completion/completion_item.rs
@@ -1,12 +1,12 @@
 use hir::{Docs, Documentation};
-use ra_syntax::{
-    ast::{self, AstNode},
-    TextRange,
-};
+use ra_syntax::TextRange;
 use ra_text_edit::TextEdit;
 use test_utils::tested_by;
 
-use crate::completion::completion_context::CompletionContext;
+use crate::completion::{
+    completion_context::CompletionContext,
+    function_label,
+};
 
 /// `CompletionItem` describes a single completion variant in the editor pop-up.
 /// It is basically a POD with various properties. To construct a
@@ -97,8 +97,8 @@ impl CompletionItem {
         self.detail.as_ref().map(|it| it.as_str())
     }
     /// A doc-comment
-    pub fn documentation(&self) -> Option<&str> {
-        self.documentation.as_ref().map(|it| it.contents())
+    pub fn documentation(&self) -> Option<Documentation> {
+        self.documentation.clone()
     }
     /// What string is used for filtering.
     pub fn lookup(&self) -> &str {
@@ -252,7 +252,7 @@ impl Builder {
             self.documentation = Some(docs);
         }
 
-        if let Some(label) = function_label(ctx, function) {
+        if let Some(label) = function_item_label(ctx, function) {
             self.detail = Some(label);
         }
 
@@ -292,24 +292,9 @@ impl Into<Vec<CompletionItem>> for Completions {
     }
 }
 
-fn function_label(ctx: &CompletionContext, function: hir::Function) -> Option<String> {
+fn function_item_label(ctx: &CompletionContext, function: hir::Function) -> Option<String> {
     let node = function.source(ctx.db).1;
-
-    let label: String = if let Some(body) = node.body() {
-        let body_range = body.syntax().range();
-        let label: String = node
-            .syntax()
-            .children()
-            .filter(|child| !child.range().is_subrange(&body_range)) // Filter out body
-            .filter(|child| ast::Comment::cast(child).is_none()) // Filter out comments
-            .map(|node| node.text().to_string())
-            .collect();
-        label
-    } else {
-        node.syntax().text().to_string()
-    };
-
-    Some(label.trim().to_owned())
+    function_label(&node)
 }
 
 #[cfg(test)]
diff --git a/crates/ra_ide_api/src/impls.rs b/crates/ra_ide_api/src/impls.rs
new file mode 100644
index 000000000..469d56d63
--- /dev/null
+++ b/crates/ra_ide_api/src/impls.rs
@@ -0,0 +1,120 @@
+use ra_db::{SourceDatabase};
+use ra_syntax::{
+    AstNode, ast,
+    algo::find_node_at_offset,
+};
+use hir::{db::HirDatabase, source_binder};
+
+use crate::{FilePosition, NavigationTarget, db::RootDatabase, RangeInfo};
+
+pub(crate) fn goto_implementation(
+    db: &RootDatabase,
+    position: FilePosition,
+) -> Option<RangeInfo<Vec<NavigationTarget>>> {
+    let file = db.parse(position.file_id);
+    let syntax = file.syntax();
+
+    let module = source_binder::module_from_position(db, position)?;
+    let krate = module.krate(db)?;
+
+    let node = find_node_at_offset::<ast::NominalDef>(syntax, position.offset)?;
+    let ty = match node.kind() {
+        ast::NominalDefKind::StructDef(def) => {
+            source_binder::struct_from_module(db, module, &def).ty(db)
+        }
+        ast::NominalDefKind::EnumDef(def) => {
+            source_binder::enum_from_module(db, module, &def).ty(db)
+        }
+    };
+
+    let impls = db.impls_in_crate(krate);
+
+    let navs = impls
+        .lookup_impl_blocks(db, &ty)
+        .map(|(module, imp)| NavigationTarget::from_impl_block(db, module, &imp));
+
+    Some(RangeInfo::new(node.syntax().range(), navs.collect()))
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::mock_analysis::analysis_and_position;
+
+    fn check_goto(fixuture: &str, expected: &[&str]) {
+        let (analysis, pos) = analysis_and_position(fixuture);
+
+        let navs = analysis.goto_implementation(pos).unwrap().unwrap().info;
+        assert_eq!(navs.len(), expected.len());
+        navs.into_iter()
+            .enumerate()
+            .for_each(|(i, nav)| nav.assert_match(expected[i]));
+    }
+
+    #[test]
+    fn goto_implementation_works() {
+        check_goto(
+            "
+            //- /lib.rs
+            struct Foo<|>;
+            impl Foo {}
+            ",
+            &["impl IMPL_BLOCK FileId(1) [12; 23)"],
+        );
+    }
+
+    #[test]
+    fn goto_implementation_works_multiple_blocks() {
+        check_goto(
+            "
+            //- /lib.rs
+            struct Foo<|>;
+            impl Foo {}
+            impl Foo {}
+            ",
+            &[
+                "impl IMPL_BLOCK FileId(1) [12; 23)",
+                "impl IMPL_BLOCK FileId(1) [24; 35)",
+            ],
+        );
+    }
+
+    #[test]
+    fn goto_implementation_works_multiple_mods() {
+        check_goto(
+            "
+            //- /lib.rs
+            struct Foo<|>;
+            mod a {
+                impl super::Foo {}
+            }
+            mod b {
+                impl super::Foo {}
+            }
+            ",
+            &[
+                "impl IMPL_BLOCK FileId(1) [24; 42)",
+                "impl IMPL_BLOCK FileId(1) [57; 75)",
+            ],
+        );
+    }
+
+    #[test]
+    fn goto_implementation_works_multiple_files() {
+        check_goto(
+            "
+            //- /lib.rs
+            struct Foo<|>;
+            mod a;
+            mod b;
+            //- /a.rs
+            impl crate::Foo {}
+            //- /b.rs
+            impl crate::Foo {}
+            ",
+            &[
+                "impl IMPL_BLOCK FileId(2) [0; 18)",
+                "impl IMPL_BLOCK FileId(3) [0; 18)",
+            ],
+        );
+    }
+}
diff --git a/crates/ra_ide_api/src/lib.rs b/crates/ra_ide_api/src/lib.rs
index 51947e4cc..5d8acf9df 100644
--- a/crates/ra_ide_api/src/lib.rs
+++ b/crates/ra_ide_api/src/lib.rs
@@ -25,6 +25,7 @@ mod call_info;
 mod syntax_highlighting;
 mod parent_module;
 mod rename;
+mod impls;
 
 #[cfg(test)]
 mod marks;
@@ -58,6 +59,7 @@ pub use ra_ide_api_light::{
 pub use ra_db::{
     Canceled, CrateGraph, CrateId, FileId, FilePosition, FileRange, SourceRootId
 };
+pub use hir::Documentation;
 
 // We use jemalloc mainly to get heap usage statistics, actual performance
 // differnece is not measures.
@@ -266,7 +268,7 @@ impl<T> RangeInfo<T> {
 #[derive(Debug)]
 pub struct CallInfo {
     pub label: String,
-    pub doc: Option<String>,
+    pub doc: Option<Documentation>,
     pub parameters: Vec<String>,
     pub active_parameter: Option<usize>,
 }
@@ -415,6 +417,13 @@ impl Analysis {
         self.with_db(|db| goto_definition::goto_definition(db, position))
     }
 
+    pub fn goto_implementation(
+        &self,
+        position: FilePosition,
+    ) -> Cancelable<Option<RangeInfo<Vec<NavigationTarget>>>> {
+        self.with_db(|db| impls::goto_implementation(db, position))
+    }
+
     /// Finds all usages of the reference at point.
     pub fn find_all_refs(&self, position: FilePosition) -> Cancelable<Vec<(FileId, TextRange)>> {
         self.with_db(|db| db.find_all_refs(position))
diff --git a/crates/ra_ide_api/src/navigation_target.rs b/crates/ra_ide_api/src/navigation_target.rs
index d73d4afa7..5ccb5cc2e 100644
--- a/crates/ra_ide_api/src/navigation_target.rs
+++ b/crates/ra_ide_api/src/navigation_target.rs
@@ -147,6 +147,16 @@ impl NavigationTarget {
         }
     }
 
+    pub(crate) fn from_impl_block(
+        db: &RootDatabase,
+        module: hir::Module,
+        impl_block: &hir::ImplBlock,
+    ) -> NavigationTarget {
+        let (file_id, _) = module.definition_source(db);
+        let node = module.impl_source(db, impl_block.id());
+        NavigationTarget::from_syntax(file_id, "impl".into(), None, node.syntax())
+    }
+
     #[cfg(test)]
     pub(crate) fn assert_match(&self, expected: &str) {
         let actual = self.debug_render();