[tests] Porting misc hot reload tests.

Change-Id: Ib77f447954049315a6a4812cf1d6066529fd9057
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/406683
Reviewed-by: Nate Biggs <natebiggs@google.com>
Commit-Queue: Mark Zhou <markzipan@google.com>

tests/hot_reload/enum_values_to_string/main.0.dart

@@ -0,0 +1,26 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L3546
+
+enum Fruit { Apple, Banana }
+
+helper() {
+  String r = '';
+  r += Fruit.Apple.toString();
+  r += ' ';
+  r += Fruit.Banana.toString();
+  return r;
+}
+
+Future<void> main() async {
+  Expect.equals('Fruit.Apple Fruit.Banana', helper());
+  await hotReload();
+
+  Expect.equals('Fruit.Apple Fruit.Cantaloupe Fruit.Banana', helper());
+}

tests/hot_reload/enum_values_to_string/main.1.dart

@@ -0,0 +1,47 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L3546
+
+enum Fruit { Apple, Cantaloupe, Banana }
+
+helper() {
+  String r = '';
+  r += Fruit.Apple.toString();
+  r += ' ';
+  r += Fruit.Cantaloupe.toString();
+  r += ' ';
+  r += Fruit.Banana.toString();
+  return r;
+}
+
+Future<void> main() async {
+  Expect.equals('Fruit.Apple Fruit.Banana', helper());
+  await hotReload();
+
+  Expect.equals('Fruit.Apple Fruit.Cantaloupe Fruit.Banana', helper());
+}
+
+/** DIFF **/
+/*
+ // Adapted from:
+ // https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L3546
+ 
+-enum Fruit { Apple, Banana }
++enum Fruit { Apple, Cantaloupe, Banana }
+ 
+ helper() {
+   String r = '';
+   r += Fruit.Apple.toString();
+   r += ' ';
++  r += Fruit.Cantaloupe.toString();
++  r += ' ';
+   r += Fruit.Banana.toString();
+   return r;
+ }
+*/

tests/hot_reload/function_replacement/main.0.dart

@@ -0,0 +1,20 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L47
+
+helper() {
+  return 4;
+}
+
+Future<void> main() async {
+  Expect.equals(4, helper());
+  await hotReload();
+
+  Expect.equals(10, helper());
+}

tests/hot_reload/function_replacement/main.1.dart

@@ -0,0 +1,32 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L47
+
+helper() {
+  return 10;
+}
+
+Future<void> main() async {
+  Expect.equals(4, helper());
+  await hotReload();
+
+  Expect.equals(10, helper());
+}
+
+/** DIFF **/
+/*
+ // https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L47
+ 
+ helper() {
+-  return 4;
++  return 10;
+ }
+ 
+ Future<void> main() async {
+*/

tests/hot_reload/patch_static_initializer_with_closure/main.0.dart

@@ -0,0 +1,20 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/174ce4005f34bc860d1a4189ff21292b0796c94b/runtime/vm/isolate_reload_test.cc#L6091
+
+dynamic field = (a) => 'a$a';
+
+Future<void> main() async {
+  dynamic f = field;
+  Expect.equals('ab', f('b'));
+  await hotReload();
+
+  dynamic g = field;
+  Expect.equals('ac', g('c'));
+}

tests/hot_reload/patch_static_initializer_with_closure/main.1.dart

@@ -0,0 +1,32 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/174ce4005f34bc860d1a4189ff21292b0796c94b/runtime/vm/isolate_reload_test.cc#L6091
+
+dynamic field = (_, __) => 'Not executed';
+
+Future<void> main() async {
+  dynamic f = field;
+  Expect.equals('ab', f('b'));
+  await hotReload();
+
+  dynamic g = field;
+  Expect.equals('ac', g('c'));
+}
+
+/** DIFF **/
+/*
+ // Adapted from:
+ // https://github.com/dart-lang/sdk/blob/174ce4005f34bc860d1a4189ff21292b0796c94b/runtime/vm/isolate_reload_test.cc#L6091
+ 
+-dynamic field = (a) => 'a$a';
++dynamic field = (_, __) => 'Not executed';
+ 
+ Future<void> main() async {
+   dynamic f = field;
+*/

tests/hot_reload/run_new_field_initializers_syntax_error/config.json

@@ -0,0 +1,5 @@
+{
+  "expectedErrors": {
+    "1": "Error: Expected an identifier, but got '...'"
+  }
+}

tests/hot_reload/run_new_field_initializers_syntax_error/main.0.dart

@@ -0,0 +1,30 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L5209
+
+// When an initializer expression has a syntax error, we detect it at reload
+// time.
+
+class Foo {
+  int x = 4;
+}
+
+late Foo value;
+helper() {
+  value = Foo();
+  return value.x;
+}
+
+Future<void> main() async {
+  Expect.equals(4, helper());
+  // Add the field y with a syntax error in the initializing expression.
+  // The reload fails because the initializing expression is parsed at
+  // class finalization time.
+  await hotReload(expectRejection: true);
+}

tests/hot_reload/run_new_field_initializers_syntax_error/main.1.reject.dart

@@ -0,0 +1,48 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L5209
+
+// When an initializer expression has a syntax error, we detect it at reload
+// time.
+
+class Foo {
+  int x = 4;
+  int y = ......;
+}
+
+late Foo value;
+helper() {
+  return value.y;
+}
+
+Future<void> main() async {
+  Expect.equals(4, helper());
+  // Add the field y with a syntax error in the initializing expression.
+  // The reload fails because the initializing expression is parsed at
+  // class finalization time.
+  await hotReload(expectRejection: true);
+}
+
+/** DIFF **/
+/*
+ 
+ class Foo {
+   int x = 4;
++  int y = ......;
+ }
+ 
+ late Foo value;
+ helper() {
+-  value = Foo();
+-  return value.x;
++  return value.y;
+ }
+ 
+ Future<void> main() async {
+*/

tests/hot_reload/run_new_field_initializers_syntax_error2/config.json

@@ -0,0 +1,5 @@
+{
+  "expectedErrors": {
+    "1": "Error: Expected an identifier, but got '...'"
+  }
+}

tests/hot_reload/run_new_field_initializers_syntax_error2/main.0.dart

@@ -0,0 +1,31 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L5247
+
+// When an initializer expression has a syntax error, we detect it at reload
+// time.
+
+class Foo {
+  Foo() { /* default constructor */ }
+  int x = 4;
+}
+
+late Foo value;
+helper() {
+  value = Foo();
+  return value.x;
+}
+
+Future<void> main() async {
+  Expect.equals(4, helper());
+  // Add the field y with a syntax error in the initializing expression.
+  // The reload fails because the initializing expression is parsed at
+  // class finalization time.
+  await hotReload(expectRejection: true);
+}

tests/hot_reload/run_new_field_initializers_syntax_error2/main.1.reject.dart

@@ -0,0 +1,49 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L5247
+
+// When an initializer expression has a syntax error, we detect it at reload
+// time.
+
+class Foo {
+  Foo() { /* default constructor */ }
+  int x = 4;
+  int y = ......;
+}
+
+late Foo value;
+helper() {
+  return value.y;
+}
+
+Future<void> main() async {
+  Expect.equals(4, helper());
+  // Add the field y with a syntax error in the initializing expression.
+  // The reload fails because the initializing expression is parsed at
+  // class finalization time.
+  await hotReload(expectRejection: true);
+}
+
+/** DIFF **/
+/*
+ class Foo {
+   Foo() { /* default constructor */ }
+   int x = 4;
++  int y = ......;
+ }
+ 
+ late Foo value;
+ helper() {
+-  value = Foo();
+-  return value.x;
++  return value.y;
+ }
+ 
+ Future<void> main() async {
+*/

tests/hot_reload/shape_change_mutual_reference/main.0.dart

@@ -0,0 +1,28 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L4140
+
+class A {
+  var x;
+  get yourself => this;
+}
+
+var retained1;
+var retained2;
+
+Future<void> main() async {
+  retained1 = new A();
+  retained2 = new A();
+  retained1.x = retained2;
+  retained2.x = retained1;
+  Expect.identical(retained1.x.yourself, retained2);
+  Expect.identical(retained2.x.yourself, retained1);
+
+  await hotReload();
+}

tests/hot_reload/shape_change_mutual_reference/main.1.dart

@@ -0,0 +1,55 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L4140
+
+class A {
+  var x;
+  var y;
+  var z;
+  var w;
+  get yourself => this;
+}
+
+var retained1;
+var retained2;
+
+Future<void> main() async {
+  retained1 = new A();
+  retained2 = new A();
+  retained1.x = retained2;
+  retained2.x = retained1;
+  Expect.identical(retained1.x.yourself, retained2);
+  Expect.identical(retained2.x.yourself, retained1);
+
+  await hotReload();
+
+  Expect.identical(retained1.x.yourself, retained2);
+  Expect.identical(retained2.x.yourself, retained1);
+}
+
+/** DIFF **/
+/*
+ 
+ class A {
+   var x;
++  var y;
++  var z;
++  var w;
+   get yourself => this;
+ }
+ 
+@@ -25,4 +28,7 @@ Future<void> main() async {
+   Expect.identical(retained2.x.yourself, retained1);
+ 
+   await hotReload();
++
++  Expect.identical(retained1.x.yourself, retained2);
++  Expect.identical(retained2.x.yourself, retained1);
+ }
+*/

tests/hot_reload/top_level_parse_error/config.json

@@ -0,0 +1,5 @@
+{
+  "expectedErrors": {
+    "1": "Variables must be declared using the keywords 'const', 'final', 'var' or a type name"
+  }
+}

tests/hot_reload/top_level_parse_error/main.0.dart

@@ -0,0 +1,18 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L1257
+
+helper() {
+  return 4;
+}
+
+Future<void> main() async {
+  Expect.equals(4, helper());
+  await hotReload(expectRejection: true);
+}

tests/hot_reload/top_level_parse_error/main.1.reject.dart

@@ -0,0 +1,30 @@
+// Copyright (c) 2025, 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:expect/expect.dart';
+import 'package:reload_test/reload_test_utils.dart';
+
+// Adapted from:
+// https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L1257
+
+kjsadkfjaksldfjklsadf;
+helper() {
+  return 4;
+}
+
+Future<void> main() async {
+  Expect.equals(4, helper());
+  await hotReload(expectRejection: true);
+}
+
+/** DIFF **/
+/*
+ // Adapted from:
+ // https://github.com/dart-lang/sdk/blob/13f5fc6b168d8b6e5843d17fb9ba77f1343a7dfe/runtime/vm/isolate_reload_test.cc#L1257
+ 
++kjsadkfjaksldfjklsadf;
+ helper() {
+   return 4;
+ }
+*/