1 files changed, 10 insertions, 1 deletions

diff --git a/crates/ra_syntax/src/ast/make.rs b/crates/ra_syntax/src/ast/make.rs
index 7b17fef49..d0e960fb4 100644
--- a/crates/ra_syntax/src/ast/make.rs
+++ b/crates/ra_syntax/src/ast/make.rs
@@ -13,6 +13,10 @@ pub fn name_ref(text: &str) -> ast::NameRef {
     ast_from_text(&format!("fn f() {{ {}; }}", text))
 }
 
+pub fn type_ref(text: &str) -> ast::TypeRef {
+    ast_from_text(&format!("impl {} for D {{}};", text))
+}
+
 pub fn path_segment(name_ref: ast::NameRef) -> ast::PathSegment {
     ast_from_text(&format!("use {};", name_ref))
 }
@@ -300,7 +304,12 @@ pub fn add_pub_crate_modifier(fn_def: ast::FnDef) -> ast::FnDef {
 
 fn ast_from_text<N: AstNode>(text: &str) -> N {
     let parse = SourceFile::parse(text);
-    let node = parse.tree().syntax().descendants().find_map(N::cast).unwrap();
+    let node = match parse.tree().syntax().descendants().find_map(N::cast) {
+        Some(it) => it,
+        None => {
+            panic!("Failed to make ast node `{}` from text {}", std::any::type_name::<N>(), text)
+        }
+    };
     let node = node.syntax().clone();
     let node = unroot(node);
     let node = N::cast(node).unwrap();