#3180. Add more tests for JS interop (#3273)

Add more tests for JS interop

Author: sgrekhov

LibTest/js_interop/interop_A01_t06.dart

@@ -0,0 +1,66 @@
+// 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.
+
+/// @assertion Within an interop type, you can declare several different types
+/// of external interop members:
+/// - Constructors. When called, constructors with only positional parameters
+///   create a new JS object whose constructor is defined by the name of the
+///   extension type using `new`.
+///
+/// @description Check that a constructor of a JS interop type with positional
+/// parameters when called creates a new JS object whose constructor is defined
+/// by the name of the extension type using `new`. Test redirecting constructor.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import '../../Utils/expect.dart';
+import 'js_utils.dart';
+
+extension type ET._(JSObject _) implements JSObject {
+  external ET(int id, String? name);
+  ET.fromId(int id) : this(id, "default");
+
+  external int get id;
+  external String? get name;
+}
+
+@JS("ET")
+extension type ET2._(JSObject _) implements JSObject {
+  external factory ET2(int id, String? name);
+  factory ET2.f(int id) => ET2(id, "default");
+  factory ET2.fromId(int id) = ET2.f;
+
+  external int get id;
+  external String? get name;
+}
+
+main() {
+  eval(r'''
+    class ET {
+      constructor(id, name) {
+        this._id = id;
+        this._name = name;
+      }
+      get id() {
+        return this._id;
+      }
+      get name() {
+        return this._name;
+      }
+    }
+    globalThis.ET = ET;
+  ''');
+
+  ET et1 = ET.fromId(1);
+  Expect.equals(1, et1.id);
+  Expect.equals("default", et1.name);
+
+  ET2 et2 = ET2.f(2);
+  Expect.equals(2, et2.id);
+  Expect.equals("default", et2.name);
+
+  ET2 et3 = ET2.fromId(3);
+  Expect.equals(3, et3.id);
+  Expect.equals("default", et3.name);
+}

LibTest/js_interop/interop_A01_t07.dart

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+// 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.
+
+/// @assertion Within an interop type, you can declare several different types
+/// of external interop members:
+/// - Constructors. When called, constructors with only positional parameters
+///   create a new JS object whose constructor is defined by the name of the
+///   extension type using `new`.
+///
+/// @description Check that a primary constructor of a JS interop type is not
+/// external and therefore its invocation does not call a JS constructor.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import '../../Utils/expect.dart';
+import 'js_utils.dart';
+
+extension type ET(JSAny v) implements JSAny {
+  external ET.create(int id, String? name);
+
+  external int? get id;
+  external String? get name;
+}
+
+main() {
+  eval(r'''
+    class ET {
+      constructor(id, name) {
+        this._id = id;
+        this._name = name;
+      }
+      get id() {
+        return this._id;
+      }
+      get name() {
+        return this._name;
+      }
+    }
+    globalThis.ET = ET;
+  ''');
+
+  ET et1 = ET(42.toJS);
+  Expect.isNull(et1.id);
+  Expect.isNull(et1.name);
+}

LibTest/js_interop/interop_A01_t08.dart

@@ -0,0 +1,52 @@
+// 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.
+
+/// @assertion Within an interop type, you can declare several different types
+/// of external interop members:
+/// - Constructors. When called, constructors with only positional parameters
+///   create a new JS object whose constructor is defined by the name of the
+///   extension type using `new`.
+///
+/// @description Check that it is not an error if a JS interop type declares a
+/// constructor but the appropriate interop object in JS doesn't declare a
+/// constructor.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../Utils/expect.dart';
+import 'js_utils.dart';
+
+extension type ET._(JSObject _) implements JSObject {
+  external ET(int id, String? name);
+
+  external int? get id;
+  external String? get name;
+}
+
+@JS("ET")
+extension type ET2._(JSObject _) implements JSObject {
+  external factory ET2(int id, String? name);
+
+  external int? get id;
+  external String? get name;
+}
+
+main() {
+  eval(r'''
+    class ET {}
+    globalThis.ET = ET;
+  ''');
+  ET et1 = ET(1, "one");
+  Expect.isNull(et1.id);
+  Expect.isNull(et1.name);
+  globalContext["et1"] = et1;
+  Expect.isNotNull(globalContext["et1"]);
+
+  ET2 et2 = ET2(2, "two");
+  Expect.isNull(et2.id);
+  Expect.isNull(et2.name);
+  globalContext["et2"] = et2;
+  Expect.isNotNull(globalContext["et2"]);
+}

LibTest/js_interop/interop_A02_t03.dart

@@ -0,0 +1,71 @@
+// 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.
+
+/// @assertion Within an interop type, you can declare several different types
+/// of external interop members:
+/// ...
+/// - Object literal constructors. It's sometimes useful to create a JS object
+///   literal that simply contains a number of properties and their values. In
+///   order to do this, declare a constructor with only named parameters, where
+///   the names of the parameters match the property names.
+///
+/// @description Check that a constructor of a JS interop type with named
+/// parameters creates a new JS object with all properties defined by the
+/// constructor. Test required named parameters.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../Utils/expect.dart';
+import 'js_utils.dart';
+
+extension type ET1._(JSObject _) implements JSObject {
+  external ET1({required int id, required String? name});
+  external ET1.fromId({required int id});
+
+  external int get id;
+  external String? get name;
+}
+
+extension type ET2._(JSObject _) implements JSObject {
+  external factory ET2({required int id, required String? name});
+  external factory ET2.fromId({required int id});
+
+  external int get id;
+  external String? get name;
+}
+
+main() {
+  globalContext["et1"] = ET1(id: 1, name: "one");
+  eval(r'''
+    globalThis.v1 = globalThis.et1.id;
+    globalThis.v2 = globalThis.et1.name;
+  ''');
+  Expect.equals(1, (globalContext["v1"] as JSNumber).toDartInt);
+  Expect.equals("one", (globalContext["v2"] as JSString).toDart);
+
+  globalContext["et2"] = ET1.fromId(id: 2);
+  eval(r'''
+    globalThis.v3 = globalThis.et2.id;
+    globalThis.v4 = globalThis.et2.name;
+  ''');
+  Expect.equals(2, (globalContext["v3"] as JSNumber).toDartInt);
+  Expect.isNull(globalContext["v4"]);
+
+  globalContext["et3"] = ET2(id: 3, name: "three");
+  eval(r'''
+    globalThis.v5 = globalThis.et3.id;
+    globalThis.v6 = globalThis.et3.name;
+  ''');
+  Expect.equals(3, (globalContext["v5"] as JSNumber).toDartInt);
+  Expect.equals("three", (globalContext["v6"] as JSString).toDart);
+
+  globalContext["et4"] = ET2.fromId(id: 4);
+  eval(r'''
+    globalThis.v7 = globalThis.et4.id;
+    globalThis.v8 = globalThis.et4.name;
+  ''');
+  Expect.equals(4, (globalContext["v7"] as JSNumber).toDartInt);
+  Expect.isNull(globalContext["v8"]);
+}

LibTest/js_interop/interop_A02_t04.dart

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+// 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.
+
+/// @assertion Within an interop type, you can declare several different types
+/// of external interop members:
+/// ...
+/// - Object literal constructors. It's sometimes useful to create a JS object
+///   literal that simply contains a number of properties and their values. In
+///   order to do this, declare a constructor with only named parameters, where
+///   the names of the parameters match the property names.
+///
+/// @description Check that a constructor of a JS interop type with named
+/// parameters creates a new JS object with all properties defined by the
+/// constructor. Test redirecting constructors.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../Utils/expect.dart';
+import 'js_utils.dart';
+
+extension type ET1._(JSObject _) implements JSObject {
+  external ET1({int id, String? name});
+  ET1.fromId({int id = 0}) : this(id: id, name: "default");
+
+  external int get id;
+  external String? get name;
+}
+
+extension type ET2._(JSObject _) implements JSObject {
+  external factory ET2({int id, String? name});
+  factory ET2.f({int id = 0}) => ET2(id: id, name: "default");
+  factory ET2.fromId({int id}) = ET2.f;
+
+  external int get id;
+  external String? get name;
+}
+
+main() {
+  globalContext["et1"] = ET1.fromId(id: 1);
+  eval(r'''
+    globalThis.v1 = globalThis.et1.id;
+    globalThis.v2 = globalThis.et1.name;
+  ''');
+  Expect.equals(1, (globalContext["v1"] as JSNumber).toDartInt);
+  Expect.equals("default", (globalContext["v2"] as JSString).toDart);
+
+  globalContext["et2"] = ET2.f(id: 2);
+  eval(r'''
+    globalThis.v3 = globalThis.et2.id;
+    globalThis.v4 = globalThis.et2.name;
+  ''');
+  Expect.equals(2, (globalContext["v3"] as JSNumber).toDartInt);
+  Expect.equals("default", (globalContext["v4"] as JSString).toDart);
+
+  globalContext["et3"] = ET2.fromId(id: 3);
+  eval(r'''
+    globalThis.v5 = globalThis.et3.id;
+    globalThis.v6 = globalThis.et3.name;
+  ''');
+  Expect.equals(3, (globalContext["v5"] as JSNumber).toDartInt);
+  Expect.equals("default", (globalContext["v6"] as JSString).toDart);
+}

LibTest/js_interop/interop_A03_t01.dart

@@ -0,0 +1,60 @@
+// 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.
+
+/// @assertion Within an interop type, you can declare several different types
+/// of external interop members:
+/// ...
+/// - static members. Like constructors, static members use the name of the
+///   extension type to generate the JS code.
+///
+/// @description Check that static members use the name of the extension type to
+/// generate the JS code.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import '../../Utils/expect.dart';
+import 'js_utils.dart';
+
+extension type ET._(JSObject _) implements JSObject {
+  external static int variable;
+  external static int get getter;
+  external static String method();
+  external static void set setter(int value);
+}
+
+@JS("ET")
+extension type ET2._(JSObject _) implements JSObject {
+  external static int variable;
+  external static int get getter;
+  external static String method();
+  external static void set setter(int value);
+}
+
+main() {
+  eval(r'''
+    class ET {
+      static variable = 42;
+      static get getter() {
+        return ET.variable;
+      }
+      static method() {
+        return "static method";
+      }
+      static set setter(value) {
+        ET.variable = value;
+      }
+    }
+    globalThis.ET = ET;
+  ''');
+
+  Expect.equals(42, ET.variable);
+  Expect.equals("static method", ET.method());
+  ET.setter = -1;
+  Expect.equals(-1, ET.getter);
+
+  Expect.equals(-1, ET2.variable);
+  Expect.equals("static method", ET2.method());
+  ET2.setter = 42;
+  Expect.equals(42, ET2.getter);
+}