fix: show no error when parameters match macro names

src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_missing_impl_members.rs

@@ -2470,4 +2470,39 @@ fn check(&self) -> b::State {
 }"#,
         );
     }
+
+    #[test]
+    fn test_parameter_names_matching_macros_not_qualified() {
+        check_assist(
+            add_missing_impl_members,
+            r#"
+trait Foo {
+    fn foo(&self, vec: usize);
+    fn bar(&self, format: String, panic: bool);
+}
+
+struct Bar;
+
+impl Foo for Bar {$0}
+"#,
+            r#"
+trait Foo {
+    fn foo(&self, vec: usize);
+    fn bar(&self, format: String, panic: bool);
+}
+
+struct Bar;
+
+impl Foo for Bar {
+    fn foo(&self, vec: usize) {
+        ${0:todo!()}
+    }
+
+    fn bar(&self, format: String, panic: bool) {
+        todo!()
+    }
+}
+"#,
+        );
+    }
 }

src/tools/rust-analyzer/crates/ide-db/src/path_transform.rs

@@ -538,6 +538,14 @@ fn transform_ident_pat(
         editor: &mut SyntaxEditor,
         ident_pat: &ast::IdentPat,
     ) -> Option<()> {
+        // Check if IdentPat is inside a function parameter.
+        // Parameter names are bindings, not references, thus should not be qualified.
+        for ancestor in ident_pat.syntax().ancestors() {
+            if ast::Param::can_cast(ancestor.kind()) {
+                return None;
+            }
+        }
+
         let name = ident_pat.name()?;
 
         let temp_path = make::path_from_text(&name.text());
@@ -546,6 +554,11 @@ fn transform_ident_pat(
 
         match resolution {
             hir::PathResolution::Def(def) if def.as_assoc_item(self.source_scope.db).is_none() => {
+                // Don't qualify macros - they can't be used in pattern position
+                if matches!(def, hir::ModuleDef::Macro(_)) {
+                    return None;
+                }
+
                 let cfg = FindPathConfig {
                     prefer_no_std: false,
                     prefer_prelude: true,