6 files changed, 494 insertions, 0 deletions

diff --git a/crates/ra_ide_api/src/completion.rs b/crates/ra_ide_api/src/completion.rs
index 4a38d62bb..d92e01bfb 100644
--- a/crates/ra_ide_api/src/completion.rs
+++ b/crates/ra_ide_api/src/completion.rs
@@ -2,6 +2,7 @@ mod completion_item;
 mod completion_context;
 
 mod complete_dot;
+mod complete_struct_literal;
 mod complete_fn_param;
 mod complete_keyword;
 mod complete_snippet;
@@ -59,6 +60,7 @@ pub(crate) fn completions(db: &db::RootDatabase, position: FilePosition) -> Opti
     complete_path::complete_path(&mut acc, &ctx);
     complete_scope::complete_scope(&mut acc, &ctx);
     complete_dot::complete_dot(&mut acc, &ctx);
+    complete_struct_literal::complete_struct_literal(&mut acc, &ctx);
     complete_postfix::complete_postfix(&mut acc, &ctx);
     Some(acc)
 }
diff --git a/crates/ra_ide_api/src/completion/complete_struct_literal.rs b/crates/ra_ide_api/src/completion/complete_struct_literal.rs
new file mode 100644
index 000000000..f8dd2baad
--- /dev/null
+++ b/crates/ra_ide_api/src/completion/complete_struct_literal.rs
@@ -0,0 +1,73 @@
+use hir::{Ty, AdtDef, Docs};
+
+use crate::completion::{CompletionContext, Completions, CompletionItem, CompletionItemKind};
+use crate::completion::completion_item::CompletionKind;
+
+/// Complete fields in fields literals.
+pub(super) fn complete_struct_literal(acc: &mut Completions, ctx: &CompletionContext) {
+    let (function, struct_lit) = match (&ctx.function, ctx.struct_lit_syntax) {
+        (Some(function), Some(struct_lit)) => (function, struct_lit),
+        _ => return,
+    };
+    let infer_result = function.infer(ctx.db);
+    let syntax_mapping = function.body_syntax_mapping(ctx.db);
+    let expr = match syntax_mapping.node_expr(struct_lit.into()) {
+        Some(expr) => expr,
+        None => return,
+    };
+    let ty = infer_result[expr].clone();
+    let (adt, substs) = match ty {
+        Ty::Adt { def_id, ref substs, .. } => (def_id, substs),
+        _ => return,
+    };
+    match adt {
+        AdtDef::Struct(s) => {
+            for field in s.fields(ctx.db) {
+                CompletionItem::new(
+                    CompletionKind::Reference,
+                    ctx.source_range(),
+                    field.name(ctx.db).to_string(),
+                )
+                .kind(CompletionItemKind::Field)
+                .detail(field.ty(ctx.db).subst(substs).to_string())
+                .set_documentation(field.docs(ctx.db))
+                .add_to(acc);
+            }
+        }
+
+        // TODO unions
+        AdtDef::Enum(_) => (),
+    };
+}
+
+#[cfg(test)]
+mod tests {
+    use insta::assert_debug_snapshot_matches;
+    use crate::completion::{CompletionItem, CompletionKind};
+
+    fn complete(code: &str) -> Vec<CompletionItem> {
+        crate::completion::completion_item::do_completion(code, CompletionKind::Reference)
+    }
+
+    #[test]
+    fn test_struct_literal_field() {
+        let completions = complete(
+            r"
+            struct A { the_field: u32 }
+            fn foo() {
+               A { the<|> }
+            }
+            ",
+        );
+        assert_debug_snapshot_matches!(completions, @r###"[
+    CompletionItem {
+        label: "the_field",
+        source_range: [83; 86),
+        delete: [83; 86),
+        insert: "the_field",
+        kind: Field,
+        detail: "u32"
+    }
+]"###);
+    }
+}
diff --git a/crates/ra_ide_api/src/completion/completion_context.rs b/crates/ra_ide_api/src/completion/completion_context.rs
index b9f0abe19..d351be054 100644
--- a/crates/ra_ide_api/src/completion/completion_context.rs
+++ b/crates/ra_ide_api/src/completion/completion_context.rs
@@ -21,6 +21,7 @@ pub(crate) struct CompletionContext<'a> {
     pub(super) function: Option<hir::Function>,
     pub(super) function_syntax: Option<&'a ast::FnDef>,
     pub(super) use_item_syntax: Option<&'a ast::UseItem>,
+    pub(super) struct_lit_syntax: Option<&'a ast::StructLit>,
     pub(super) is_param: bool,
     /// A single-indent path, like `foo`. `::foo` should not be considered a trivial path.
     pub(super) is_trivial_path: bool,
@@ -55,6 +56,7 @@ impl<'a> CompletionContext<'a> {
             function: None,
             function_syntax: None,
             use_item_syntax: None,
+            struct_lit_syntax: None,
             is_param: false,
             is_trivial_path: false,
             path_prefix: None,
@@ -108,6 +110,10 @@ impl<'a> CompletionContext<'a> {
     }
     fn classify_name_ref(&mut self, original_file: &'a SourceFile, name_ref: &ast::NameRef) {
         let name_range = name_ref.syntax().range();
+        if name_ref.syntax().parent().and_then(ast::NamedField::cast).is_some() {
+            self.struct_lit_syntax = find_node_at_offset(original_file.syntax(), self.offset);
+        }
+
         let top_node =
             name_ref.syntax().ancestors().take_while(|it| it.range() == name_range).last().unwrap();
 
diff --git a/crates/ra_syntax/src/ast.rs b/crates/ra_syntax/src/ast.rs
index 20e0a6856..56fb7c20c 100644
--- a/crates/ra_syntax/src/ast.rs
+++ b/crates/ra_syntax/src/ast.rs
@@ -724,6 +724,12 @@ impl LiteralExpr {
     }
 }
 
+impl NamedField {
+    pub fn parent_struct_lit(&self) -> &StructLit {
+        self.syntax().ancestors().find_map(StructLit::cast).unwrap()
+    }
+}
+
 impl BindPat {
     pub fn is_mutable(&self) -> bool {
         self.syntax().children().any(|n| n.kind() == MUT_KW)
diff --git a/crates/ra_syntax/src/ast/generated.rs b/crates/ra_syntax/src/ast/generated.rs
index 47107a58b..aa88b1e28 100644
--- a/crates/ra_syntax/src/ast/generated.rs
+++ b/crates/ra_syntax/src/ast/generated.rs
@@ -834,6 +834,142 @@ pub enum ExprKind<'a> {
     BinExpr(&'a BinExpr),
     Literal(&'a Literal),
 }
+impl<'a> From<&'a TupleExpr> for &'a Expr {
+    fn from(n: &'a TupleExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ArrayExpr> for &'a Expr {
+    fn from(n: &'a ArrayExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ParenExpr> for &'a Expr {
+    fn from(n: &'a ParenExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a PathExpr> for &'a Expr {
+    fn from(n: &'a PathExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a LambdaExpr> for &'a Expr {
+    fn from(n: &'a LambdaExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a IfExpr> for &'a Expr {
+    fn from(n: &'a IfExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a LoopExpr> for &'a Expr {
+    fn from(n: &'a LoopExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ForExpr> for &'a Expr {
+    fn from(n: &'a ForExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a WhileExpr> for &'a Expr {
+    fn from(n: &'a WhileExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ContinueExpr> for &'a Expr {
+    fn from(n: &'a ContinueExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a BreakExpr> for &'a Expr {
+    fn from(n: &'a BreakExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a Label> for &'a Expr {
+    fn from(n: &'a Label) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a BlockExpr> for &'a Expr {
+    fn from(n: &'a BlockExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ReturnExpr> for &'a Expr {
+    fn from(n: &'a ReturnExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a MatchExpr> for &'a Expr {
+    fn from(n: &'a MatchExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a StructLit> for &'a Expr {
+    fn from(n: &'a StructLit) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a CallExpr> for &'a Expr {
+    fn from(n: &'a CallExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a IndexExpr> for &'a Expr {
+    fn from(n: &'a IndexExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a MethodCallExpr> for &'a Expr {
+    fn from(n: &'a MethodCallExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a FieldExpr> for &'a Expr {
+    fn from(n: &'a FieldExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a TryExpr> for &'a Expr {
+    fn from(n: &'a TryExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a CastExpr> for &'a Expr {
+    fn from(n: &'a CastExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a RefExpr> for &'a Expr {
+    fn from(n: &'a RefExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a PrefixExpr> for &'a Expr {
+    fn from(n: &'a PrefixExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a RangeExpr> for &'a Expr {
+    fn from(n: &'a RangeExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a BinExpr> for &'a Expr {
+    fn from(n: &'a BinExpr) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a Literal> for &'a Expr {
+    fn from(n: &'a Literal) -> &'a Expr {
+        Expr::cast(&n.syntax).unwrap()
+    }
+}
+
 
 impl AstNode for Expr {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
@@ -1375,6 +1511,22 @@ pub enum ImplItemKind<'a> {
     TypeDef(&'a TypeDef),
     ConstDef(&'a ConstDef),
 }
+impl<'a> From<&'a FnDef> for &'a ImplItem {
+    fn from(n: &'a FnDef) -> &'a ImplItem {
+        ImplItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a TypeDef> for &'a ImplItem {
+    fn from(n: &'a TypeDef) -> &'a ImplItem {
+        ImplItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ConstDef> for &'a ImplItem {
+    fn from(n: &'a ConstDef) -> &'a ImplItem {
+        ImplItem::cast(&n.syntax).unwrap()
+    }
+}
+
 
 impl AstNode for ImplItem {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
@@ -1778,6 +1930,57 @@ pub enum LiteralExprKind<'a> {
     TrueKw(&'a TrueKw),
     FalseKw(&'a FalseKw),
 }
+impl<'a> From<&'a String> for &'a LiteralExpr {
+    fn from(n: &'a String) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ByteString> for &'a LiteralExpr {
+    fn from(n: &'a ByteString) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a RawString> for &'a LiteralExpr {
+    fn from(n: &'a RawString) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a RawByteString> for &'a LiteralExpr {
+    fn from(n: &'a RawByteString) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a Char> for &'a LiteralExpr {
+    fn from(n: &'a Char) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a Byte> for &'a LiteralExpr {
+    fn from(n: &'a Byte) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a IntNumber> for &'a LiteralExpr {
+    fn from(n: &'a IntNumber) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a FloatNumber> for &'a LiteralExpr {
+    fn from(n: &'a FloatNumber) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a TrueKw> for &'a LiteralExpr {
+    fn from(n: &'a TrueKw) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a FalseKw> for &'a LiteralExpr {
+    fn from(n: &'a FalseKw) -> &'a LiteralExpr {
+        LiteralExpr::cast(&n.syntax).unwrap()
+    }
+}
+
 
 impl AstNode for LiteralExpr {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
@@ -2164,6 +2367,62 @@ pub enum ModuleItemKind<'a> {
     StaticDef(&'a StaticDef),
     Module(&'a Module),
 }
+impl<'a> From<&'a StructDef> for &'a ModuleItem {
+    fn from(n: &'a StructDef) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a EnumDef> for &'a ModuleItem {
+    fn from(n: &'a EnumDef) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a FnDef> for &'a ModuleItem {
+    fn from(n: &'a FnDef) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a TraitDef> for &'a ModuleItem {
+    fn from(n: &'a TraitDef) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a TypeDef> for &'a ModuleItem {
+    fn from(n: &'a TypeDef) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ImplBlock> for &'a ModuleItem {
+    fn from(n: &'a ImplBlock) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a UseItem> for &'a ModuleItem {
+    fn from(n: &'a UseItem) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ExternCrateItem> for &'a ModuleItem {
+    fn from(n: &'a ExternCrateItem) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ConstDef> for &'a ModuleItem {
+    fn from(n: &'a ConstDef) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a StaticDef> for &'a ModuleItem {
+    fn from(n: &'a StaticDef) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a Module> for &'a ModuleItem {
+    fn from(n: &'a Module) -> &'a ModuleItem {
+        ModuleItem::cast(&n.syntax).unwrap()
+    }
+}
+
 
 impl AstNode for ModuleItem {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
@@ -2446,6 +2705,17 @@ pub enum NominalDefKind<'a> {
     StructDef(&'a StructDef),
     EnumDef(&'a EnumDef),
 }
+impl<'a> From<&'a StructDef> for &'a NominalDef {
+    fn from(n: &'a StructDef) -> &'a NominalDef {
+        NominalDef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a EnumDef> for &'a NominalDef {
+    fn from(n: &'a EnumDef) -> &'a NominalDef {
+        NominalDef::cast(&n.syntax).unwrap()
+    }
+}
+
 
 impl AstNode for NominalDef {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
@@ -2637,6 +2907,57 @@ pub enum PatKind<'a> {
     RangePat(&'a RangePat),
     LiteralPat(&'a LiteralPat),
 }
+impl<'a> From<&'a RefPat> for &'a Pat {
+    fn from(n: &'a RefPat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a BindPat> for &'a Pat {
+    fn from(n: &'a BindPat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a PlaceholderPat> for &'a Pat {
+    fn from(n: &'a PlaceholderPat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a PathPat> for &'a Pat {
+    fn from(n: &'a PathPat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a StructPat> for &'a Pat {
+    fn from(n: &'a StructPat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a TupleStructPat> for &'a Pat {
+    fn from(n: &'a TupleStructPat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a TuplePat> for &'a Pat {
+    fn from(n: &'a TuplePat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a SlicePat> for &'a Pat {
+    fn from(n: &'a SlicePat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a RangePat> for &'a Pat {
+    fn from(n: &'a RangePat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a LiteralPat> for &'a Pat {
+    fn from(n: &'a LiteralPat) -> &'a Pat {
+        Pat::cast(&n.syntax).unwrap()
+    }
+}
+
 
 impl AstNode for Pat {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
@@ -3520,6 +3841,17 @@ pub enum StmtKind<'a> {
     ExprStmt(&'a ExprStmt),
     LetStmt(&'a LetStmt),
 }
+impl<'a> From<&'a ExprStmt> for &'a Stmt {
+    fn from(n: &'a ExprStmt) -> &'a Stmt {
+        Stmt::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a LetStmt> for &'a Stmt {
+    fn from(n: &'a LetStmt) -> &'a Stmt {
+        Stmt::cast(&n.syntax).unwrap()
+    }
+}
+
 
 impl AstNode for Stmt {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
@@ -4142,6 +4474,72 @@ pub enum TypeRefKind<'a> {
     ImplTraitType(&'a ImplTraitType),
     DynTraitType(&'a DynTraitType),
 }
+impl<'a> From<&'a ParenType> for &'a TypeRef {
+    fn from(n: &'a ParenType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a TupleType> for &'a TypeRef {
+    fn from(n: &'a TupleType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a NeverType> for &'a TypeRef {
+    fn from(n: &'a NeverType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a PathType> for &'a TypeRef {
+    fn from(n: &'a PathType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a PointerType> for &'a TypeRef {
+    fn from(n: &'a PointerType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ArrayType> for &'a TypeRef {
+    fn from(n: &'a ArrayType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a SliceType> for &'a TypeRef {
+    fn from(n: &'a SliceType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ReferenceType> for &'a TypeRef {
+    fn from(n: &'a ReferenceType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a PlaceholderType> for &'a TypeRef {
+    fn from(n: &'a PlaceholderType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a FnPointerType> for &'a TypeRef {
+    fn from(n: &'a FnPointerType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ForType> for &'a TypeRef {
+    fn from(n: &'a ForType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a ImplTraitType> for &'a TypeRef {
+    fn from(n: &'a ImplTraitType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+impl<'a> From<&'a DynTraitType> for &'a TypeRef {
+    fn from(n: &'a DynTraitType) -> &'a TypeRef {
+        TypeRef::cast(&n.syntax).unwrap()
+    }
+}
+
 
 impl AstNode for TypeRef {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
diff --git a/crates/ra_syntax/src/ast/generated.rs.tera b/crates/ra_syntax/src/ast/generated.rs.tera
index ca7a28581..e2d4856cf 100644
--- a/crates/ra_syntax/src/ast/generated.rs.tera
+++ b/crates/ra_syntax/src/ast/generated.rs.tera
@@ -38,6 +38,15 @@ pub enum {{ node }}Kind<'a> {
 {%- endfor %}
 }
 
+{%- for kind in methods.enum %}
+impl<'a> From<&'a {{ kind }}> for &'a {{ node }} {
+    fn from(n: &'a {{ kind }}) -> &'a {{ node }} {
+        {{ node }}::cast(&n.syntax).unwrap()
+    }
+}
+{%- endfor %}
+
+
 impl AstNode for {{ node }} {
     fn cast(syntax: &SyntaxNode) -> Option<&Self> {
         match syntax.kind() {