1 files changed, 47 insertions, 15 deletions

diff --git a/crates/ra_mbe/src/tests.rs b/crates/ra_mbe/src/tests.rs
index 44f381938..a7fcea0ac 100644
--- a/crates/ra_mbe/src/tests.rs
+++ b/crates/ra_mbe/src/tests.rs
@@ -427,22 +427,28 @@ MACRO_ITEMS@[0; 40)
     );
 }
 
-#[test]
-fn test_expand_literals_to_token_tree() {
-    fn to_subtree(tt: &tt::TokenTree) -> &tt::Subtree {
-        if let tt::TokenTree::Subtree(subtree) = tt {
-            return &subtree;
-        }
-        unreachable!("It is not a subtree");
+fn to_subtree(tt: &tt::TokenTree) -> &tt::Subtree {
+    if let tt::TokenTree::Subtree(subtree) = tt {
+        return &subtree;
     }
+    unreachable!("It is not a subtree");
+}
+fn to_literal(tt: &tt::TokenTree) -> &tt::Literal {
+    if let tt::TokenTree::Leaf(tt::Leaf::Literal(lit)) = tt {
+        return lit;
+    }
+    unreachable!("It is not a literal");
+}
 
-    fn to_literal(tt: &tt::TokenTree) -> &tt::Literal {
-        if let tt::TokenTree::Leaf(tt::Leaf::Literal(lit)) = tt {
-            return lit;
-        }
-        unreachable!("It is not a literal");
+fn to_punct(tt: &tt::TokenTree) -> &tt::Punct {
+    if let tt::TokenTree::Leaf(tt::Leaf::Punct(lit)) = tt {
+        return lit;
     }
+    unreachable!("It is not a Punct");
+}
 
+#[test]
+fn test_expand_literals_to_token_tree() {
     let expansion = parse_macro(
         r#"
             macro_rules! literals {
@@ -471,6 +477,22 @@ fn test_expand_literals_to_token_tree() {
 }
 
 #[test]
+fn test_attr_to_token_tree() {
+    let expansion = parse_to_token_tree_by_syntax(
+        r#"
+            #[derive(Copy)]
+            struct Foo;
+            "#,
+    );
+
+    assert_eq!(to_punct(&expansion.token_trees[0]).char, '#');
+    assert_eq!(
+        to_subtree(&expansion.token_trees[1]).delimiter_kind(),
+        Some(tt::DelimiterKind::Bracket)
+    );
+}
+
+#[test]
 fn test_two_idents() {
     parse_macro(
         r#"
@@ -1427,8 +1449,8 @@ impl MacroFixture {
         let macro_invocation =
             source_file.syntax().descendants().find_map(ast::MacroCall::cast).unwrap();
 
-        let (invocation_tt, _) =
-            ast_to_token_tree(&macro_invocation.token_tree().unwrap()).unwrap();
+        let (invocation_tt, _) = ast_to_token_tree(&macro_invocation.token_tree().unwrap())
+            .ok_or_else(|| ExpandError::ConversionError)?;
 
         self.rules.expand(&invocation_tt).result()
     }
@@ -1517,6 +1539,16 @@ pub(crate) fn parse_macro(ra_fixture: &str) -> MacroFixture {
     MacroFixture { rules }
 }
 
+pub(crate) fn parse_to_token_tree_by_syntax(ra_fixture: &str) -> tt::Subtree {
+    let source_file = ast::SourceFile::parse(ra_fixture).ok().unwrap();
+    let tt = syntax_node_to_token_tree(source_file.syntax()).unwrap().0;
+
+    let parsed = parse_to_token_tree(ra_fixture).unwrap().0;
+    assert_eq!(tt, parsed);
+
+    parsed
+}
+
 fn debug_dump_ignore_spaces(node: &ra_syntax::SyntaxNode) -> String {
     let mut level = 0;
     let mut buf = String::new();
@@ -1662,5 +1694,5 @@ fn test_expand_bad_literal() {
         macro_rules! foo { ($i:literal) => {}; }
     "#,
     )
-    .assert_expand_err(r#"foo!(&k");"#, &ExpandError::BindingError("".to_string()));
+    .assert_expand_err(r#"foo!(&k");"#, &ExpandError::BindingError("".into()));
 }