Don't insert !() if there's already some

crates/ra_ide/src/completion/completion_context.rs

@@ -50,6 +50,8 @@ pub(crate) struct CompletionContext<'a> {
     pub(super) dot_receiver_is_ambiguous_float_literal: bool,
     /// If this is a call (method or function) in particular, i.e. the () are already there.
     pub(super) is_call: bool,
+    /// If this is a macro call, i.e. the () are already there.
+    pub(super) is_macro_call: bool,
     pub(super) is_path_type: bool,
     pub(super) has_type_args: bool,
 }
@@ -102,6 +104,7 @@ impl<'a> CompletionContext<'a> {
             is_new_item: false,
             dot_receiver: None,
             is_call: false,
+            is_macro_call: false,
             is_path_type: false,
             has_type_args: false,
             dot_receiver_is_ambiguous_float_literal: false,
@@ -269,6 +272,7 @@ impl<'a> CompletionContext<'a> {
                 .and_then(ast::PathExpr::cast)
                 .and_then(|it| it.syntax().parent().and_then(ast::CallExpr::cast))
                 .is_some();
+            self.is_macro_call = path.syntax().parent().and_then(ast::MacroCall::cast).is_some();
 
             self.is_path_type = path.syntax().parent().and_then(ast::PathType::cast).is_some();
             self.has_type_args = segment.type_arg_list().is_some();

crates/ra_ide/src/completion/presentation.rs

@@ -174,7 +174,8 @@ impl Completions {
                 .set_deprecated(is_deprecated(macro_, ctx.db))
                 .detail(detail);
 
-        builder = if ctx.use_item_syntax.is_some() {
+        builder = if ctx.use_item_syntax.is_some() || ctx.is_macro_call {
+            tested_by!(dont_insert_macro_call_parens_unncessary);
             builder.insert_text(name)
         } else {
             let macro_braces_to_insert =
@@ -960,7 +961,8 @@ mod tests {
     }
 
     #[test]
-    fn dont_insert_macro_call_braces_in_use() {
+    fn dont_insert_macro_call_parens_unncessary() {
+        covers!(dont_insert_macro_call_parens_unncessary);
         assert_debug_snapshot!(
             do_reference_completion(
                 r"
@@ -986,6 +988,41 @@ mod tests {
             },
         ]
         "###
-        )
+        );
+
+        assert_debug_snapshot!(
+            do_reference_completion(
+                r"
+                //- /main.rs
+                macro_rules frobnicate {
+                    () => ()
+                }
+                fn main() {
+                    frob<|>!();
+                }
+                "
+            ),
+            @r###"
+        [
+            CompletionItem {
+                label: "frobnicate!",
+                source_range: [56; 60),
+                delete: [56; 60),
+                insert: "frobnicate",
+                kind: Macro,
+                detail: "macro_rules! frobnicate",
+            },
+            CompletionItem {
+                label: "main()",
+                source_range: [56; 60),
+                delete: [56; 60),
+                insert: "main()$0",
+                kind: Function,
+                lookup: "main",
+                detail: "fn main()",
+            },
+        ]
+        "###
+        );
     }
 }

crates/ra_ide/src/marks.rs

@@ -7,4 +7,5 @@ test_utils::marks!(
     dont_complete_current_use
     test_resolve_parent_module_on_module_decl
     search_filters_by_range
+    dont_insert_macro_call_parens_unncessary
 );