6 files changed, 202 insertions, 17 deletions

diff --git a/crates/libeditor/src/code_actions.rs b/crates/libeditor/src/code_actions.rs
index 684b8243a..08a85f6e2 100644
--- a/crates/libeditor/src/code_actions.rs
+++ b/crates/libeditor/src/code_actions.rs
@@ -80,7 +80,9 @@ pub fn add_impl<'a>(file: &'a File, offset: TextUnit) -> Option<impl FnOnce() ->
         buf.push_str(" ");
         buf.push_str(name.text().as_str());
         if let Some(type_params) = type_params {
-            join(type_params.type_params().filter_map(|it| it.name()).map(|it| it.text()))
+            let lifetime_params = type_params.lifetime_params().filter_map(|it| it.lifetime()).map(|it| it.text());
+            let type_params = type_params.type_params().filter_map(|it| it.name()).map(|it| it.text());
+            join(lifetime_params.chain(type_params))
                 .surround_with("<", ">")
                 .to_buf(&mut buf);
         }
@@ -146,6 +148,11 @@ mod tests {
             "struct Foo<T: Clone> {}\n\nimpl<T: Clone> Foo<T> {\n<|>\n}",
             |file, off| add_impl(file, off).map(|f| f()),
         );
+        check_action(
+            "struct Foo<'a, T: Foo<'a>> {<|>}",
+            "struct Foo<'a, T: Foo<'a>> {}\n\nimpl<'a, T: Foo<'a>> Foo<'a, T> {\n<|>\n}",
+            |file, off| add_impl(file, off).map(|f| f()),
+        );
     }
 
 }
diff --git a/crates/libeditor/src/scope/fn_scope.rs b/crates/libeditor/src/scope/fn_scope.rs
index e807c6c71..a38647c43 100644
--- a/crates/libeditor/src/scope/fn_scope.rs
+++ b/crates/libeditor/src/scope/fn_scope.rs
@@ -24,11 +24,7 @@ impl FnScopes {
             scope_for: HashMap::new()
         };
         let root = scopes.root_scope();
-        fn_def.param_list().into_iter()
-            .flat_map(|it| it.params())
-            .filter_map(|it| it.pat())
-            .for_each(|it| scopes.add_bindings(root, it));
-
+        scopes.add_params_bindings(root, fn_def.param_list());
         if let Some(body) = fn_def.body() {
             compute_block_scopes(body, &mut scopes, root)
         }
@@ -56,6 +52,12 @@ impl FnScopes {
             .filter_map(ScopeEntry::new);
         self.scopes[scope].entries.extend(entries);
     }
+    fn add_params_bindings(&mut self, scope: ScopeId, params: Option<ast::ParamList>) {
+        params.into_iter()
+            .flat_map(|it| it.params())
+            .filter_map(|it| it.pat())
+            .for_each(|it| self.add_bindings(scope, it));
+    }
     fn set_scope(&mut self, node: SyntaxNodeRef, scope: ScopeId) {
         self.scope_for.insert(node.owned(), scope);
     }
@@ -102,13 +104,14 @@ fn compute_block_scopes(block: ast::Block, scopes: &mut FnScopes, mut scope: Sco
     for stmt in block.statements() {
         match stmt {
             ast::Stmt::LetStmt(stmt) => {
+                if let Some(expr) = stmt.initializer() {
+                    scopes.set_scope(expr.syntax(), scope);
+                    compute_expr_scopes(expr, scopes, scope);
+                }
                 scope = scopes.new_scope(scope);
                 if let Some(pat) = stmt.pat() {
                     scopes.add_bindings(scope, pat);
                 }
-                if let Some(expr) = stmt.initializer() {
-                    scopes.set_scope(expr.syntax(), scope)
-                }
             }
             ast::Stmt::ExprStmt(expr_stmt) => {
                 if let Some(expr) = expr_stmt.expr() {
@@ -163,6 +166,20 @@ fn compute_expr_scopes(expr: ast::Expr, scopes: &mut FnScopes, scope: ScopeId) {
                 compute_block_scopes(block, scopes, scope);
             }
         },
+        ast::Expr::LambdaExpr(e) => {
+            let mut scope = scopes.new_scope(scope);
+            scopes.add_params_bindings(scope, e.param_list());
+            if let Some(body) = e.body() {
+                scopes.set_scope(body.syntax(), scope);
+                compute_expr_scopes(body, scopes, scope);
+            }
+        }
+        ast::Expr::CallExpr(e) => {
+            e.arg_list().into_iter()
+                .flat_map(|it| it.args())
+                .chain(e.expr())
+                .for_each(|expr| compute_expr_scopes(expr, scopes, scope));
+        }
         _ => {
             expr.syntax().children()
                 .filter_map(ast::Expr::cast)
@@ -189,3 +206,53 @@ struct ScopeData {
     parent: Option<ScopeId>,
     entries: Vec<ScopeEntry>
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use libsyntax2::File;
+    use {find_node_at_offset, test_utils::extract_offset};
+
+    fn do_check(code: &str, expected: &[&str]) {
+        let (off, code) = extract_offset(code);
+        let code = {
+            let mut buf = String::new();
+            let off = u32::from(off) as usize;
+            buf.push_str(&code[..off]);
+            buf.push_str("marker");
+            buf.push_str(&code[off..]);
+            buf
+        };
+        let file = File::parse(&code);
+        let marker: ast::PathExpr = find_node_at_offset(file.syntax(), off).unwrap();
+        let fn_def: ast::FnDef = find_node_at_offset(file.syntax(), off).unwrap();
+        let scopes = FnScopes::new(fn_def);
+        let actual = scopes.scope_chain(marker.syntax())
+            .flat_map(|scope| scopes.entries(scope))
+            .map(|it| it.name())
+            .collect::<Vec<_>>();
+        assert_eq!(expected, actual.as_slice());
+    }
+
+    #[test]
+    fn test_lambda_scope() {
+        do_check(r"
+            fn quux(foo: i32) {
+                let f = |bar| {
+                    <|>
+                };
+            }",
+            &["bar", "foo"],
+        );
+    }
+
+    #[test]
+    fn test_call_scope() {
+        do_check(r"
+            fn quux() {
+                f(|x| <|> );
+            }",
+            &["x"],
+        );
+    }
+}
diff --git a/crates/libsyntax2/src/ast/generated.rs b/crates/libsyntax2/src/ast/generated.rs
index e8743caa8..d72e2091a 100644
--- a/crates/libsyntax2/src/ast/generated.rs
+++ b/crates/libsyntax2/src/ast/generated.rs
@@ -4,6 +4,28 @@ use {
     SyntaxKind::*,
 };
 
+// ArgList
+#[derive(Debug, Clone, Copy)]
+pub struct ArgList<'a> {
+    syntax: SyntaxNodeRef<'a>,
+}
+
+impl<'a> AstNode<'a> for ArgList<'a> {
+    fn cast(syntax: SyntaxNodeRef<'a>) -> Option<Self> {
+        match syntax.kind() {
+            ARG_LIST => Some(ArgList { syntax }),
+            _ => None,
+        }
+    }
+    fn syntax(self) -> SyntaxNodeRef<'a> { self.syntax }
+}
+
+impl<'a> ArgList<'a> {
+    pub fn args(self) -> impl Iterator<Item = Expr<'a>> + 'a {
+        super::children(self)
+    }
+}
+
 // ArrayExpr
 #[derive(Debug, Clone, Copy)]
 pub struct ArrayExpr<'a> {
@@ -181,7 +203,15 @@ impl<'a> AstNode<'a> for CallExpr<'a> {
     fn syntax(self) -> SyntaxNodeRef<'a> { self.syntax }
 }
 
-impl<'a> CallExpr<'a> {}
+impl<'a> CallExpr<'a> {
+    pub fn expr(self) -> Option<Expr<'a>> {
+        super::child_opt(self)
+    }
+
+    pub fn arg_list(self) -> Option<ArgList<'a>> {
+        super::child_opt(self)
+    }
+}
 
 // CastExpr
 #[derive(Debug, Clone, Copy)]
@@ -705,7 +735,15 @@ impl<'a> AstNode<'a> for LambdaExpr<'a> {
     fn syntax(self) -> SyntaxNodeRef<'a> { self.syntax }
 }
 
-impl<'a> LambdaExpr<'a> {}
+impl<'a> LambdaExpr<'a> {
+    pub fn param_list(self) -> Option<ParamList<'a>> {
+        super::child_opt(self)
+    }
+
+    pub fn body(self) -> Option<Expr<'a>> {
+        super::child_opt(self)
+    }
+}
 
 // LetStmt
 #[derive(Debug, Clone, Copy)]
@@ -733,6 +771,46 @@ impl<'a> LetStmt<'a> {
     }
 }
 
+// Lifetime
+#[derive(Debug, Clone, Copy)]
+pub struct Lifetime<'a> {
+    syntax: SyntaxNodeRef<'a>,
+}
+
+impl<'a> AstNode<'a> for Lifetime<'a> {
+    fn cast(syntax: SyntaxNodeRef<'a>) -> Option<Self> {
+        match syntax.kind() {
+            LIFETIME => Some(Lifetime { syntax }),
+            _ => None,
+        }
+    }
+    fn syntax(self) -> SyntaxNodeRef<'a> { self.syntax }
+}
+
+impl<'a> Lifetime<'a> {}
+
+// LifetimeParam
+#[derive(Debug, Clone, Copy)]
+pub struct LifetimeParam<'a> {
+    syntax: SyntaxNodeRef<'a>,
+}
+
+impl<'a> AstNode<'a> for LifetimeParam<'a> {
+    fn cast(syntax: SyntaxNodeRef<'a>) -> Option<Self> {
+        match syntax.kind() {
+            LIFETIME_PARAM => Some(LifetimeParam { syntax }),
+            _ => None,
+        }
+    }
+    fn syntax(self) -> SyntaxNodeRef<'a> { self.syntax }
+}
+
+impl<'a> LifetimeParam<'a> {
+    pub fn lifetime(self) -> Option<Lifetime<'a>> {
+        super::child_opt(self)
+    }
+}
+
 // Literal
 #[derive(Debug, Clone, Copy)]
 pub struct Literal<'a> {
@@ -1813,6 +1891,10 @@ impl<'a> TypeParamList<'a> {
     pub fn type_params(self) -> impl Iterator<Item = TypeParam<'a>> + 'a {
         super::children(self)
     }
+
+    pub fn lifetime_params(self) -> impl Iterator<Item = LifetimeParam<'a>> + 'a {
+        super::children(self)
+    }
 }
 
 // TypeRef
diff --git a/crates/libsyntax2/src/ast/mod.rs b/crates/libsyntax2/src/ast/mod.rs
index 9941138a7..3b5e9269f 100644
--- a/crates/libsyntax2/src/ast/mod.rs
+++ b/crates/libsyntax2/src/ast/mod.rs
@@ -67,6 +67,12 @@ impl<'a> Attr<'a> {
     }
 }
 
+impl<'a> Lifetime<'a> {
+    pub fn text(&self) -> SmolStr {
+        self.syntax().leaf_text().unwrap()
+    }
+}
+
 impl<'a> Name<'a> {
     pub fn text(&self) -> SmolStr {
         let ident = self.syntax().first_child()
diff --git a/crates/libsyntax2/src/grammar.ron b/crates/libsyntax2/src/grammar.ron
index f1907d1ce..3c293d3e4 100644
--- a/crates/libsyntax2/src/grammar.ron
+++ b/crates/libsyntax2/src/grammar.ron
@@ -344,7 +344,12 @@ Grammar(
         "ArrayExpr": (),
         "ParenExpr": (),
         "PathExpr": (),
-        "LambdaExpr": (),
+        "LambdaExpr": (
+            options: [
+                ["param_list", "ParamList"],
+                ["body", "Expr"],
+            ]
+        ),
         "IfExpr": (
             options: [ ["condition", "Condition"] ]
         ),
@@ -378,7 +383,12 @@ Grammar(
         "StructLit": (),
         "NamedFieldList": (),
         "NamedField": (),
-        "CallExpr": (),
+        "CallExpr": (
+            options: [
+                [ "expr", "Expr" ],
+                [ "arg_list", "ArgList" ],
+            ]
+        ),
         "IndexExpr": (),
         "MethodCallExpr": (),
         "FieldExpr": (),
@@ -457,8 +467,15 @@ Grammar(
         "NameRef": (),
         "Attr": ( options: [ ["value", "TokenTree"] ] ),
         "TokenTree": (),
-        "TypeParamList": ( collections: [ ["type_params", "TypeParam" ] ]),
+        "TypeParamList": (
+            collections: [
+                ["type_params", "TypeParam" ],
+                ["lifetime_params", "LifetimeParam" ],
+            ]
+        ),
         "TypeParam": ( traits: ["NameOwner"] ),
+        "LifetimeParam": ( options: [ ["lifetime", "Lifetime"] ] ),
+        "Lifetime": (),
         "WhereClause": (),
         "ExprStmt": (
             options: [ ["expr", "Expr"] ]
@@ -492,5 +509,10 @@ Grammar(
         ),
         "UseItem": (),
         "ExternCrateItem": (),
+        "ArgList": (
+            collections: [
+                ["args", "Expr"]
+            ]
+        )
     },
 )
diff --git a/crates/libsyntax2/src/grammar/expressions/atom.rs b/crates/libsyntax2/src/grammar/expressions/atom.rs
index 0769bb5a8..a17c27b31 100644
--- a/crates/libsyntax2/src/grammar/expressions/atom.rs
+++ b/crates/libsyntax2/src/grammar/expressions/atom.rs
@@ -151,10 +151,11 @@ fn lambda_expr(p: &mut Parser) -> CompletedMarker {
     p.eat(MOVE_KW);
     params::param_list_opt_types(p);
     if opt_fn_ret_type(p) {
-        block(p);
-    } else {
-        expr(p);
+        if !p.at(L_CURLY) {
+            p.error("expected `{`");
+        }
     }
+    expr(p);
     m.complete(p, LAMBDA_EXPR)
 }