Merge #5417

5417: Mismatched arg count works for lambdas r=jonas-schievink a=matklad



Co-authored-by: Aleksey Kladov <[email protected]>

2 files changed, 37 insertions, 2 deletions

diff --git a/crates/ra_ide/src/call_info.rs b/crates/ra_ide/src/call_info.rs
index 35a8a0dc5..14980afdd 100644
--- a/crates/ra_ide/src/call_info.rs
+++ b/crates/ra_ide/src/call_info.rs
@@ -70,6 +70,7 @@ pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<Cal
                 variant.name(db)
             );
         }
+        hir::CallableKind::Closure => (),
     }
 
     res.signature.push('(');
@@ -93,7 +94,7 @@ pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<Cal
     res.signature.push(')');
 
     match callable.kind() {
-        hir::CallableKind::Function(_) => {
+        hir::CallableKind::Function(_) | hir::CallableKind::Closure => {
             let ret_type = callable.return_type();
             if !ret_type.is_unit() {
                 format_to!(res.signature, " -> {}", ret_type.display(db));
@@ -702,4 +703,36 @@ id! {
             "#]],
         );
     }
+
+    #[test]
+    fn call_info_for_lambdas() {
+        check(
+            r#"
+struct S;
+fn foo(s: S) -> i32 { 92 }
+fn main() {
+    (|s| foo(s))(<|>)
+}
+        "#,
+            expect![[r#"
+                (S) -> i32
+                (<S>)
+            "#]],
+        )
+    }
+
+    #[test]
+    fn call_info_for_fn_ptr() {
+        check(
+            r#"
+fn main(f: fn(i32, f64) -> char) {
+    f(0, <|>)
+}
+        "#,
+            expect![[r#"
+                (i32, f64) -> char
+                (i32, <f64>)
+            "#]],
+        )
+    }
 }
diff --git a/crates/ra_ide/src/inlay_hints.rs b/crates/ra_ide/src/inlay_hints.rs
index cec3b04e8..43a5e29b5 100644
--- a/crates/ra_ide/src/inlay_hints.rs
+++ b/crates/ra_ide/src/inlay_hints.rs
@@ -262,7 +262,9 @@ fn should_show_param_name_hint(
     let param_name = param_name.trim_start_matches('_');
     let fn_name = match callable.kind() {
         hir::CallableKind::Function(it) => Some(it.name(sema.db).to_string()),
-        hir::CallableKind::TupleStruct(_) | hir::CallableKind::TupleEnumVariant(_) => None,
+        hir::CallableKind::TupleStruct(_)
+        | hir::CallableKind::TupleEnumVariant(_)
+        | hir::CallableKind::Closure => None,
     };
     if param_name.is_empty()
         || Some(param_name) == fn_name.as_ref().map(|s| s.trim_start_matches('_'))