10 files changed, 135 insertions, 56 deletions

diff --git a/crates/ra_hir/src/code_model_impl/function/scope.rs b/crates/ra_hir/src/code_model_impl/function/scope.rs
index 7d938c0dd..afca1e9f8 100644
--- a/crates/ra_hir/src/code_model_impl/function/scope.rs
+++ b/crates/ra_hir/src/code_model_impl/function/scope.rs
@@ -422,6 +422,9 @@ mod tests {
     fn do_check_local_name(code: &str, expected_offset: u32) {
         let (off, code) = extract_offset(code);
         let file = SourceFile::parse(&code);
+        let expected_name = find_node_at_offset::<ast::Name>(file.syntax(), expected_offset.into())
+            .expect("failed to find a name at the target offset");
+
         let fn_def: &ast::FnDef = find_node_at_offset(file.syntax(), off).unwrap();
         let name_ref: &ast::NameRef = find_node_at_offset(file.syntax(), off).unwrap();
 
@@ -431,11 +434,8 @@ mod tests {
             scopes: Arc::new(scopes),
             syntax_mapping: Arc::new(body_hir),
         };
-
         let local_name_entry = scopes.resolve_local_name(name_ref).unwrap();
         let local_name = local_name_entry.ptr();
-        let expected_name =
-            find_node_at_offset::<ast::Name>(file.syntax(), expected_offset.into()).unwrap();
         assert_eq!(local_name.range(), expected_name.syntax().range());
     }
 
@@ -470,11 +470,26 @@ mod tests {
     fn test_resolve_local_name_shadow() {
         do_check_local_name(
             r"
-        fn foo(x: String) {
-            let x : &str = &x;
-            x<|>
-        }",
-            46,
+            fn foo(x: String) {
+                let x : &str = &x;
+                x<|>
+            }
+            ",
+            53,
+        );
+    }
+
+    #[test]
+    fn ref_patterns_contribute_bindings() {
+        do_check_local_name(
+            r"
+            fn foo() {
+                if let Some(&from) = bar() {
+                    from<|>;
+                }
+            }
+            ",
+            53,
         );
     }
 }
diff --git a/crates/ra_hir/src/expr.rs b/crates/ra_hir/src/expr.rs
index 67e123e4d..593fe1598 100644
--- a/crates/ra_hir/src/expr.rs
+++ b/crates/ra_hir/src/expr.rs
@@ -315,15 +315,20 @@ pub enum Pat {
         path: Option<Path>,
         args: Vec<PatId>,
     },
+    Ref {
+        pat: PatId,
+        mutability: Mutability,
+    },
 }
 
 impl Pat {
-    pub fn walk_child_pats(&self, f: impl FnMut(PatId)) {
+    pub fn walk_child_pats(&self, mut f: impl FnMut(PatId)) {
         match self {
             Pat::Missing | Pat::Bind { .. } => {}
             Pat::TupleStruct { args, .. } => {
                 args.iter().map(|pat| *pat).for_each(f);
             }
+            Pat::Ref { pat, .. } => f(*pat),
         }
     }
 }
@@ -684,6 +689,11 @@ impl ExprCollector {
                 let args = p.args().map(|p| self.collect_pat(p)).collect();
                 self.alloc_pat(Pat::TupleStruct { path, args }, syntax_ptr)
             }
+            ast::PatKind::RefPat(p) => {
+                let pat = self.collect_pat_opt(p.pat());
+                let mutability = Mutability::from_mutable(p.is_mut());
+                self.alloc_pat(Pat::Ref { pat, mutability }, syntax_ptr)
+            }
             _ => {
                 // TODO
                 self.alloc_pat(Pat::Missing, syntax_ptr)
diff --git a/crates/ra_ide_api/src/goto_definition.rs b/crates/ra_ide_api/src/goto_definition.rs
index 8d2ff561a..e2537758d 100644
--- a/crates/ra_ide_api/src/goto_definition.rs
+++ b/crates/ra_ide_api/src/goto_definition.rs
@@ -13,8 +13,11 @@ pub(crate) fn goto_definition(
     let file = 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 navs = reference_definition(db, position.file_id, name_ref)?;
-        return Ok(Some(RangeInfo::new(name_ref.syntax().range(), navs)));
+        let navs = reference_definition(db, position.file_id, name_ref)?.to_vec();
+        return Ok(Some(RangeInfo::new(
+            name_ref.syntax().range(),
+            navs.to_vec(),
+        )));
     }
     if let Some(name) = find_node_at_offset::<ast::Name>(syntax, position.offset) {
         let navs = ctry!(name_definition(db, position.file_id, name)?);
@@ -23,11 +26,27 @@ pub(crate) fn goto_definition(
     Ok(None)
 }
 
+pub(crate) enum ReferenceResult {
+    Exact(NavigationTarget),
+    Approximate(Vec<NavigationTarget>),
+}
+
+impl ReferenceResult {
+    fn to_vec(self) -> Vec<NavigationTarget> {
+        use self::ReferenceResult::*;
+        match self {
+            Exact(target) => vec![target],
+            Approximate(vec) => vec,
+        }
+    }
+}
+
 pub(crate) fn reference_definition(
     db: &RootDatabase,
     file_id: FileId,
     name_ref: &ast::NameRef,
-) -> Cancelable<Vec<NavigationTarget>> {
+) -> Cancelable<ReferenceResult> {
+    use self::ReferenceResult::*;
     if let Some(fn_descr) =
         hir::source_binder::function_from_child_node(db, file_id, name_ref.syntax())?
     {
@@ -35,7 +54,7 @@ pub(crate) fn reference_definition(
         // First try to resolve the symbol locally
         if let Some(entry) = scope.resolve_local_name(name_ref) {
             let nav = NavigationTarget::from_scope_entry(file_id, &entry);
-            return Ok(vec![nav]);
+            return Ok(Exact(nav));
         };
     }
     // Then try module name resolution
@@ -51,7 +70,7 @@ pub(crate) fn reference_definition(
             let resolved = module.resolve_path(db, &path)?;
             if let Some(def_id) = resolved.take_types().or(resolved.take_values()) {
                 if let Some(target) = NavigationTarget::from_def(db, def_id.resolve(db)?)? {
-                    return Ok(vec![target]);
+                    return Ok(Exact(target));
                 }
             }
         }
@@ -62,7 +81,7 @@ pub(crate) fn reference_definition(
         .into_iter()
         .map(NavigationTarget::from_symbol)
         .collect();
-    Ok(navs)
+    Ok(Approximate(navs))
 }
 
 fn name_definition(
diff --git a/crates/ra_ide_api/src/hover.rs b/crates/ra_ide_api/src/hover.rs
index b66774cdf..2968b807c 100644
--- a/crates/ra_ide_api/src/hover.rs
+++ b/crates/ra_ide_api/src/hover.rs
@@ -16,9 +16,16 @@ pub(crate) fn hover(
 
     let mut range = None;
     if let Some(name_ref) = find_node_at_offset::<ast::NameRef>(file.syntax(), position.offset) {
-        let navs = crate::goto_definition::reference_definition(db, position.file_id, name_ref)?;
-        for nav in navs {
-            res.extend(doc_text_for(db, nav)?)
+        use crate::goto_definition::{ReferenceResult::*, reference_definition};
+        let ref_result = reference_definition(db, position.file_id, name_ref)?;
+        match ref_result {
+            Exact(nav) => res.extend(doc_text_for(db, nav)?),
+            Approximate(navs) => {
+                res.push("Failed to exactly resolve the symbol. This is probably because rust_analyzer does not yet support glob imports or traits.  \nThese methods were found instead:".to_string());
+                for nav in navs {
+                    res.extend(doc_text_for(db, nav)?)
+                }
+            }
         }
         if !res.is_empty() {
             range = Some(name_ref.syntax().range())
@@ -34,7 +41,7 @@ pub(crate) fn hover(
             file_id: position.file_id,
             range: node.range(),
         };
-        res.extend(type_of(db, frange)?);
+        res.extend(type_of(db, frange)?.map(Into::into));
         range = Some(node.range());
     };
 
diff --git a/crates/ra_ide_api/src/runnables.rs b/crates/ra_ide_api/src/runnables.rs
index 98b1d2d55..53e49da5b 100644
--- a/crates/ra_ide_api/src/runnables.rs
+++ b/crates/ra_ide_api/src/runnables.rs
@@ -17,6 +17,7 @@ pub struct Runnable {
 pub enum RunnableKind {
     Test { name: String },
     TestMod { path: String },
+    Bench { name: String },
     Bin,
 }
 
@@ -48,6 +49,10 @@ fn runnable_fn(fn_def: &ast::FnDef) -> Option<Runnable> {
         RunnableKind::Test {
             name: name.to_string(),
         }
+    } else if fn_def.has_atom_attr("bench") {
+        RunnableKind::Bench {
+            name: name.to_string(),
+        }
     } else {
         return None;
     };
diff --git a/crates/ra_lsp_server/src/cargo_target_spec.rs b/crates/ra_lsp_server/src/cargo_target_spec.rs
index a66f14b82..db9496bbe 100644
--- a/crates/ra_lsp_server/src/cargo_target_spec.rs
+++ b/crates/ra_lsp_server/src/cargo_target_spec.rs
@@ -32,6 +32,15 @@ pub(crate) fn runnable_args(
             res.push(path.to_string());
             res.push("--nocapture".to_string());
         }
+        RunnableKind::Bench { name } => {
+            res.push("bench".to_string());
+            if let Some(spec) = spec {
+                spec.push_to(&mut res);
+            }
+            res.push("--".to_string());
+            res.push(name.to_string());
+            res.push("--nocapture".to_string());
+        }
         RunnableKind::Bin => {
             res.push("run".to_string());
             if let Some(spec) = spec {
diff --git a/crates/ra_lsp_server/src/main_loop/handlers.rs b/crates/ra_lsp_server/src/main_loop/handlers.rs
index a781df181..7326a727d 100644
--- a/crates/ra_lsp_server/src/main_loop/handlers.rs
+++ b/crates/ra_lsp_server/src/main_loop/handlers.rs
@@ -2,22 +2,23 @@ use std::collections::HashMap;
 
 use gen_lsp_server::ErrorCode;
 use languageserver_types::{
-    CodeActionResponse, Command, CodeLens, Diagnostic, DiagnosticSeverity, DocumentFormattingParams,
-    DocumentHighlight, DocumentSymbol, Documentation, FoldingRange, FoldingRangeKind,
-    FoldingRangeParams, Hover, HoverContents, Location, MarkupContent, MarkupKind,
-    ParameterInformation, ParameterLabel, Position, PrepareRenameResponse, Range, RenameParams,
-    SignatureInformation, SymbolInformation, TextDocumentIdentifier, TextEdit, WorkspaceEdit,
+    CodeActionResponse, CodeLens, Command, Diagnostic, DiagnosticSeverity,
+    DocumentFormattingParams, DocumentHighlight, DocumentSymbol, Documentation, FoldingRange,
+    FoldingRangeKind, FoldingRangeParams, Hover, HoverContents, Location, MarkupContent,
+    MarkupKind, ParameterInformation, ParameterLabel, Position, PrepareRenameResponse, Range,
+    RenameParams, SignatureInformation, SymbolInformation, TextDocumentIdentifier, TextEdit,
+    WorkspaceEdit,
 };
 use ra_ide_api::{
-    FileId, FilePosition, FileRange, FoldKind, Query, RunnableKind, Severity, RangeInfo,
+    FileId, FilePosition, FileRange, FoldKind, Query, RangeInfo, RunnableKind, Severity,
 };
-use ra_syntax::{TextUnit, AstNode};
+use ra_syntax::{AstNode, TextUnit};
 use rustc_hash::FxHashMap;
 use serde_json::to_value;
 use std::io::Write;
 
 use crate::{
-    cargo_target_spec::{CargoTargetSpec, runnable_args},
+    cargo_target_spec::{runnable_args, CargoTargetSpec},
     conv::{to_location, to_location_link, Conv, ConvWith, MapConvWith, TryConvWith},
     req::{self, Decoration},
     server_world::ServerWorld,
@@ -258,6 +259,7 @@ pub fn handle_runnables(
             label: match &runnable.kind {
                 RunnableKind::Test { name } => format!("test {}", name),
                 RunnableKind::TestMod { path } => format!("test-mod {}", path),
+                RunnableKind::Bench { name } => format!("bench {}", name),
                 RunnableKind::Bin => "run binary".to_string(),
             },
             bin: "cargo".to_string(),
@@ -586,35 +588,37 @@ pub fn handle_code_lens(
     let mut lenses: Vec<CodeLens> = Default::default();
 
     for runnable in world.analysis().runnables(file_id)? {
-        match &runnable.kind {
-            RunnableKind::Test { name: _ } | RunnableKind::TestMod { path: _ } => {
-                let args = runnable_args(&world, file_id, &runnable.kind)?;
-
-                let range = runnable.range.conv_with(&line_index);
-
-                // This represents the actual command that will be run.
-                let r: req::Runnable = req::Runnable {
-                    range,
-                    label: Default::default(),
-                    bin: "cargo".into(),
-                    args,
-                    env: Default::default(),
-                };
+        let title = match &runnable.kind {
+            RunnableKind::Test { name: _ } | RunnableKind::TestMod { path: _ } => Some("Run Test"),
+            RunnableKind::Bench { name: _ } => Some("Run Bench"),
+            _ => None,
+        };
 
-                let lens = CodeLens {
-                    range,
-                    command: Some(Command {
-                        title: "Run Test".into(),
-                        command: "ra-lsp.run-single".into(),
-                        arguments: Some(vec![to_value(r).unwrap()]),
-                    }),
-                    data: None,
-                };
+        if let Some(title) = title {
+            let args = runnable_args(&world, file_id, &runnable.kind)?;
+            let range = runnable.range.conv_with(&line_index);
+
+            // This represents the actual command that will be run.
+            let r: req::Runnable = req::Runnable {
+                range,
+                label: Default::default(),
+                bin: "cargo".into(),
+                args,
+                env: Default::default(),
+            };
 
-                lenses.push(lens);
-            }
-            _ => continue,
-        };
+            let lens = CodeLens {
+                range,
+                command: Some(Command {
+                    title: title.into(),
+                    command: "ra-lsp.run-single".into(),
+                    arguments: Some(vec![to_value(r).unwrap()]),
+                }),
+                data: None,
+            };
+
+            lenses.push(lens);
+        }
     }
 
     return Ok(Some(lenses));
diff --git a/crates/ra_syntax/src/ast.rs b/crates/ra_syntax/src/ast.rs
index 123a7a6b9..8bf439b60 100644
--- a/crates/ra_syntax/src/ast.rs
+++ b/crates/ra_syntax/src/ast.rs
@@ -348,6 +348,12 @@ impl UseTreeList {
     }
 }
 
+impl RefPat {
+    pub fn is_mut(&self) -> bool {
+        self.syntax().children().any(|n| n.kind() == MUT_KW)
+    }
+}
+
 fn child_opt<P: AstNode, C: AstNode>(parent: &P) -> Option<&C> {
     children(parent).next()
 }
diff --git a/crates/ra_syntax/src/ast/generated.rs b/crates/ra_syntax/src/ast/generated.rs
index 1f6055115..f745cb1cb 100644
--- a/crates/ra_syntax/src/ast/generated.rs
+++ b/crates/ra_syntax/src/ast/generated.rs
@@ -2456,7 +2456,11 @@ impl AstNode for RefPat {
 }
 
 
-impl RefPat {}
+impl RefPat {
+    pub fn pat(&self) -> Option<&Pat> {
+        super::child_opt(self)
+    }
+}
 
 // ReferenceType
 #[derive(Debug, PartialEq, Eq, Hash)]
diff --git a/crates/ra_syntax/src/grammar.ron b/crates/ra_syntax/src/grammar.ron
index bddd96a5c..bac62fa04 100644
--- a/crates/ra_syntax/src/grammar.ron
+++ b/crates/ra_syntax/src/grammar.ron
@@ -462,7 +462,7 @@ Grammar(
             ],
         ),
 
-        "RefPat": (),
+        "RefPat": ( options: [ "Pat" ]),
         "BindPat": ( traits: ["NameOwner"] ),
         "PlaceholderPat": (),
         "PathPat": (),