[wildcards] UNUSED_CATCH_CLAUSE tests

Fixes: https://github.com/dart-lang/sdk/issues/55721
Change-Id: I5e675c61a7d1eb0f6192f98146fd2dbd5dd0e2e5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/366407
Commit-Queue: Phil Quitslund <pquitslund@google.com>
Reviewed-by: Kallen Tu <kallentu@google.com>

pkg/analyzer/test/src/diagnostics/unused_catch_clause_test.dart

@@ -2,6 +2,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/src/error/codes.g.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -10,6 +11,7 @@ import '../dart/resolution/context_collection_resolution.dart';
 main() {
   defineReflectiveSuite(() {
     defineReflectiveTests(UnusedCatchClauseTest);
+    defineReflectiveTests(UnusedCatchClauseTestWildCardVariablesTest);
   });
 }
 
@@ -27,6 +29,16 @@ main() {
     ]);
   }
 
+  test_on_unusedStack_wildcard() async {
+    await assertNoErrorsInCode(r'''
+main() {
+  try {
+  } on String catch (exception, _) {
+  }
+}
+''');
+  }
+
   test_on_usedException() async {
     await assertNoErrorsInCode(r'''
 main() {
@@ -48,6 +60,26 @@ main() {
 ''');
   }
 
+  test_unusedException_underscores() async {
+    await assertNoErrorsInCode(r'''
+main() {
+  try {
+  } catch (__) {
+  }
+}
+''');
+  }
+
+  test_unusedException_wildcard() async {
+    await assertNoErrorsInCode(r'''
+main() {
+  try {
+  } catch (_) {
+  }
+}
+''');
+  }
+
   test_usedException() async {
     await assertNoErrorsInCode(r'''
 main() {
@@ -59,3 +91,24 @@ main() {
 ''');
   }
 }
+
+@reflectiveTest
+class UnusedCatchClauseTestWildCardVariablesTest extends UnusedCatchClauseTest {
+  @override
+  List<String> get experiments => [
+        ...super.experiments,
+        Feature.wildcard_variables.enableString,
+      ];
+
+  test_on_unusedStack_underscores() async {
+    await assertErrorsInCode(r'''
+main() {
+  try {
+  } on String catch (exception, __) {
+  }
+}
+''', [
+      error(WarningCode.UNUSED_CATCH_STACK, 49, 2),
+    ]);
+  }
+}