analyzer: Add a failing test for #38188

Also move tests for illegal_async_return_type

Change-Id: Icd76c1ece456470ce734df2ac6628d5aedcd6e8e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/129940
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Samuel Rawlins <srawlins@google.com>

pkg/analyzer/test/generated/static_type_warning_code_test.dart

@@ -435,52 +435,6 @@ class C {
     ]);
   }
 
-  test_illegalAsyncReturnType_function_nonFuture() async {
-    await assertErrorsInCode('''
-int f() async {}
-''', [
-      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 0, 3),
-      error(HintCode.MISSING_RETURN, 4, 1),
-    ]);
-  }
-
-  test_illegalAsyncReturnType_function_subtypeOfFuture() async {
-    await assertErrorsInCode('''
-import 'dart:async';
-abstract class SubFuture<T> implements Future<T> {}
-SubFuture<int> f() async {
-  return 0;
-}
-''', [
-      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 73, 14),
-    ]);
-  }
-
-  test_illegalAsyncReturnType_method_nonFuture() async {
-    await assertErrorsInCode('''
-class C {
-  int m() async {}
-}
-''', [
-      error(HintCode.MISSING_RETURN, 16, 1),
-      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 12, 3),
-    ]);
-  }
-
-  test_illegalAsyncReturnType_method_subtypeOfFuture() async {
-    await assertErrorsInCode('''
-import 'dart:async';
-abstract class SubFuture<T> implements Future<T> {}
-class C {
-  SubFuture<int> m() async {
-    return 0;
-  }
-}
-''', [
-      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 85, 14),
-    ]);
-  }
-
   test_illegalSyncGeneratorReturnType_function_nonIterator() async {
     await assertErrorsInCode('''
 int f() sync* {}

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

@@ -0,0 +1,74 @@
+// Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file
+// 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/src/error/codes.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import '../dart/resolution/driver_resolution.dart';
+
+main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(IllegalAsyncReturnTypeTest);
+  });
+}
+
+@reflectiveTest
+class IllegalAsyncReturnTypeTest extends DriverResolutionTest {
+  test_function_nonFuture() async {
+    await assertErrorsInCode('''
+int f() async {}
+''', [
+      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 0, 3),
+      error(HintCode.MISSING_RETURN, 4, 1),
+    ]);
+  }
+
+  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/38188')
+  test_function_nonFuture_withReturn() async {
+    await assertErrorsInCode('''
+int f() async {
+  return 2;
+}
+''', [
+      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 0, 3),
+    ]);
+  }
+
+  test_function_subtypeOfFuture() async {
+    await assertErrorsInCode('''
+import 'dart:async';
+abstract class SubFuture<T> implements Future<T> {}
+SubFuture<int> f() async {
+  return 0;
+}
+''', [
+      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 73, 14),
+    ]);
+  }
+
+  test_method_nonFuture() async {
+    await assertErrorsInCode('''
+class C {
+  int m() async {}
+}
+''', [
+      error(HintCode.MISSING_RETURN, 16, 1),
+      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 12, 3),
+    ]);
+  }
+
+  test_method_subtypeOfFuture() async {
+    await assertErrorsInCode('''
+import 'dart:async';
+abstract class SubFuture<T> implements Future<T> {}
+class C {
+  SubFuture<int> m() async {
+    return 0;
+  }
+}
+''', [
+      error(StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE, 85, 14),
+    ]);
+  }
+}

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

@@ -139,6 +139,7 @@ import 'for_in_with_const_variable_test.dart' as for_in_with_const_variable;
 import 'generic_struct_subclass_test.dart' as generic_struct_subclass;
 import 'if_element_condition_from_deferred_library_test.dart'
     as if_element_condition_from_deferred_library;
+import 'illegal_async_return_type_test.dart' as illegal_async_return_type;
 import 'implements_disallowed_class_test.dart' as implements_disallowed_class;
 import 'implements_non_class_test.dart' as implements_non_class;
 import 'implements_super_class_test.dart' as implements_super_class;
@@ -570,6 +571,7 @@ main() {
     for_in_with_const_variable.main();
     generic_struct_subclass.main();
     if_element_condition_from_deferred_library.main();
+    illegal_async_return_type.main();
     implements_disallowed_class.main();
     implements_non_class.main();
     implements_super_class.main();