#3180. Add isA tests. Part 1. (#3263)

Add `isA` tests. Part 1.

Author: sgrekhov

LibTest/js_interop/JSAnyUtilityExtension/isA_A01_t01.dart

@@ -0,0 +1,29 @@
+// 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 bool isA<T extends JSAny?>()
+/// Whether this [JSAny?] is an instance of the JavaScript type that is declared
+/// by `T`.
+///
+/// Since the type-check this function emits is determined at compile-time, `T`
+/// needs to be an interop extension type that can also be determined at
+/// compile-time. In particular, `isA` can't be provided a generic type variable
+/// as a type argument.
+///
+/// @description Checks that it is a compile-time error id `T` is a type
+/// variable.
+/// @author [email protected]
+
+import 'dart:js_interop';
+
+test<T extends JSAny?>(JSAny? v) {
+  v.isA<T>();
+//      ^
+// [analyzer] unspecified
+// [web] unspecified
+}
+
+main() {
+  test<JSObject>(JSObject());
+}

LibTest/js_interop/JSAnyUtilityExtension/isA_A02_t01.dart

@@ -0,0 +1,77 @@
+// 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 bool isA<T extends JSAny?>()
+/// Whether this [JSAny?] is an instance of the JavaScript type that is declared
+/// by `T`.
+/// ...
+/// If `T` is a primitive JS type like [JSString], this uses a `typeof` check
+/// that corresponds to that primitive type like `typeofEquals('string')`.
+///
+/// @description Checks that `isA` works as expected for JS non-nullable
+/// primitive types.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../../Utils/expect.dart';
+import '../js_utils.dart';
+
+main() {
+  eval(r'''
+    globalThis.s = "JS string";
+    globalThis.b = false;
+    globalThis.n1 = 42;
+    globalThis.n2 = 3.14;
+    globalThis.bi = 123456789n;
+    globalThis.smb = Symbol();
+  ''');
+  Expect.isTrue(globalContext["s"].isA<JSString>());
+  Expect.isTrue(globalContext["s"].isA<JSAny>());
+  Expect.isFalse(globalContext["s"].isA<JSObject>());
+  Expect.isFalse(globalContext["s"].isA<JSNumber>());
+  Expect.isFalse(globalContext["s"].isA<JSBoolean>());
+  Expect.isFalse(globalContext["s"].isA<JSSymbol>());
+  Expect.isFalse(globalContext["s"].isA<JSBigInt>());
+
+  Expect.isTrue(globalContext["b"].isA<JSBoolean>());
+  Expect.isTrue(globalContext["b"].isA<JSAny>());
+  Expect.isFalse(globalContext["b"].isA<JSObject>());
+  Expect.isFalse(globalContext["b"].isA<JSNumber>());
+  Expect.isFalse(globalContext["b"].isA<JSString>());
+  Expect.isFalse(globalContext["b"].isA<JSSymbol>());
+  Expect.isFalse(globalContext["b"].isA<JSBigInt>());
+
+  Expect.isTrue(globalContext["n1"].isA<JSNumber>());
+  Expect.isTrue(globalContext["n1"].isA<JSAny>());
+  Expect.isFalse(globalContext["n1"].isA<JSObject>());
+  Expect.isFalse(globalContext["n1"].isA<JSBoolean>());
+  Expect.isFalse(globalContext["n1"].isA<JSString>());
+  Expect.isFalse(globalContext["n1"].isA<JSSymbol>());
+  Expect.isFalse(globalContext["n1"].isA<JSBigInt>());
+
+  Expect.isTrue(globalContext["n2"].isA<JSNumber>());
+  Expect.isTrue(globalContext["n2"].isA<JSAny>());
+  Expect.isFalse(globalContext["n2"].isA<JSObject>());
+  Expect.isFalse(globalContext["n2"].isA<JSBoolean>());
+  Expect.isFalse(globalContext["n2"].isA<JSString>());
+  Expect.isFalse(globalContext["n2"].isA<JSSymbol>());
+  Expect.isFalse(globalContext["n2"].isA<JSBigInt>());
+
+  Expect.isTrue(globalContext["bi"].isA<JSBigInt>());
+  Expect.isTrue(globalContext["bi"].isA<JSAny>());
+  Expect.isFalse(globalContext["bi"].isA<JSObject>());
+  Expect.isFalse(globalContext["bi"].isA<JSNumber>());
+  Expect.isFalse(globalContext["bi"].isA<JSBoolean>());
+  Expect.isFalse(globalContext["bi"].isA<JSSymbol>());
+  Expect.isFalse(globalContext["bi"].isA<JSString>());
+
+  Expect.isTrue(globalContext["smb"].isA<JSSymbol>());
+  Expect.isTrue(globalContext["smb"].isA<JSAny>());
+  Expect.isFalse(globalContext["smb"].isA<JSObject>());
+  Expect.isFalse(globalContext["smb"].isA<JSNumber>());
+  Expect.isFalse(globalContext["smb"].isA<JSBoolean>());
+  Expect.isFalse(globalContext["smb"].isA<JSBigInt>());
+  Expect.isFalse(globalContext["smb"].isA<JSString>());
+}

LibTest/js_interop/JSAnyUtilityExtension/isA_A02_t02.dart

@@ -0,0 +1,43 @@
+// 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 bool isA<T extends JSAny?>()
+/// Whether this [JSAny?] is an instance of the JavaScript type that is declared
+/// by `T`.
+/// ...
+/// If `T` is a primitive JS type like [JSString], this uses a `typeof` check
+/// that corresponds to that primitive type like `typeofEquals('string')`.
+///
+/// @description Checks that `isA` works as expected for JS `null` and
+/// `undefined` values.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../../Utils/expect.dart';
+import '../js_utils.dart';
+
+main() {
+  eval(r'''
+    globalThis.n = null;
+    globalThis.u = undefined;
+  ''');
+  Expect.isFalse(globalContext["n"].isA<JSString>());
+  Expect.isFalse(globalContext["n"].isA<JSObject>());
+  Expect.isFalse(globalContext["n"].isA<JSAny>());
+  Expect.isFalse(globalContext["n"].isA<JSNumber>());
+  Expect.isFalse(globalContext["n"].isA<JSBoolean>());
+  Expect.isFalse(globalContext["n"].isA<JSSymbol>());
+  Expect.isFalse(globalContext["n"].isA<JSBigInt>());
+  Expect.isTrue(globalContext["n"].isA<JSAny?>());
+
+  Expect.isFalse(globalContext["u"].isA<JSString>());
+  Expect.isFalse(globalContext["u"].isA<JSObject>());
+  Expect.isFalse(globalContext["u"].isA<JSAny>());
+  Expect.isFalse(globalContext["u"].isA<JSNumber>());
+  Expect.isFalse(globalContext["u"].isA<JSBoolean>());
+  Expect.isFalse(globalContext["u"].isA<JSSymbol>());
+  Expect.isFalse(globalContext["u"].isA<JSBigInt>());
+  Expect.isTrue(globalContext["u"].isA<JSAny?>());
+}

LibTest/js_interop/JSAnyUtilityExtension/isA_A02_t03.dart

@@ -0,0 +1,94 @@
+// 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 bool isA<T extends JSAny?>()
+/// Whether this [JSAny?] is an instance of the JavaScript type that is declared
+/// by `T`.
+/// ...
+/// If `T` is a primitive JS type like [JSString], this uses a `typeof` check
+/// that corresponds to that primitive type like `typeofEquals('string')`.
+///
+/// @description Checks that `isA` works as expected for JS nullable primitive
+/// types.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../../Utils/expect.dart';
+import '../js_utils.dart';
+
+main() {
+  eval(r'''
+    globalThis.s = "JS string";
+    globalThis.b = false;
+    globalThis.n1 = 42;
+    globalThis.n2 = 3.14;
+    globalThis.bi = 123456789n;
+    globalThis.smb = Symbol();
+    globalThis.n = null;
+  ''');
+  Expect.isTrue(globalContext["s"].isA<JSString?>());
+  Expect.isTrue(globalContext["s"].isA<JSAny?>());
+  Expect.isFalse(globalContext["s"].isA<JSObject?>());
+  Expect.isFalse(globalContext["s"].isA<JSNumber?>());
+  Expect.isFalse(globalContext["s"].isA<JSBoolean?>());
+  Expect.isFalse(globalContext["s"].isA<JSSymbol?>());
+  Expect.isFalse(globalContext["s"].isA<JSBigInt?>());
+
+  Expect.isTrue(globalContext["b"].isA<JSBoolean?>());
+  Expect.isTrue(globalContext["b"].isA<JSAny?>());
+  Expect.isFalse(globalContext["b"].isA<JSObject?>());
+  Expect.isFalse(globalContext["b"].isA<JSNumber?>());
+  Expect.isFalse(globalContext["b"].isA<JSString?>());
+  Expect.isFalse(globalContext["b"].isA<JSSymbol?>());
+  Expect.isFalse(globalContext["b"].isA<JSBigInt?>());
+
+  Expect.isTrue(globalContext["n1"].isA<JSNumber?>());
+  Expect.isTrue(globalContext["n1"].isA<JSAny?>());
+  Expect.isFalse(globalContext["n1"].isA<JSObject?>());
+  Expect.isFalse(globalContext["n1"].isA<JSBoolean?>());
+  Expect.isFalse(globalContext["n1"].isA<JSString?>());
+  Expect.isFalse(globalContext["n1"].isA<JSSymbol?>());
+  Expect.isFalse(globalContext["n1"].isA<JSBigInt?>());
+
+  Expect.isTrue(globalContext["n2"].isA<JSNumber?>());
+  Expect.isTrue(globalContext["n2"].isA<JSAny?>());
+  Expect.isFalse(globalContext["n2"].isA<JSObject?>());
+  Expect.isFalse(globalContext["n2"].isA<JSBoolean?>());
+  Expect.isFalse(globalContext["n2"].isA<JSString?>());
+  Expect.isFalse(globalContext["n2"].isA<JSSymbol?>());
+  Expect.isFalse(globalContext["n2"].isA<JSBigInt?>());
+
+  Expect.isTrue(globalContext["bi"].isA<JSBigInt?>());
+  Expect.isTrue(globalContext["bi"].isA<JSAny?>());
+  Expect.isFalse(globalContext["bi"].isA<JSObject?>());
+  Expect.isFalse(globalContext["bi"].isA<JSNumber?>());
+  Expect.isFalse(globalContext["bi"].isA<JSBoolean?>());
+  Expect.isFalse(globalContext["bi"].isA<JSSymbol?>());
+  Expect.isFalse(globalContext["bi"].isA<JSString?>());
+
+  Expect.isTrue(globalContext["smb"].isA<JSSymbol?>());
+  Expect.isTrue(globalContext["smb"].isA<JSAny?>());
+  Expect.isFalse(globalContext["smb"].isA<JSObject?>());
+  Expect.isFalse(globalContext["smb"].isA<JSNumber?>());
+  Expect.isFalse(globalContext["smb"].isA<JSBoolean?>());
+  Expect.isFalse(globalContext["smb"].isA<JSBigInt?>());
+  Expect.isFalse(globalContext["smb"].isA<JSString?>());
+
+  Expect.isTrue(globalContext["n"].isA<JSSymbol?>());
+  Expect.isTrue(globalContext["n"].isA<JSAny?>());
+  Expect.isTrue(globalContext["n"].isA<JSObject?>());
+  Expect.isTrue(globalContext["n"].isA<JSNumber?>());
+  Expect.isTrue(globalContext["n"].isA<JSBoolean?>());
+  Expect.isTrue(globalContext["n"].isA<JSBigInt?>());
+  Expect.isTrue(globalContext["n"].isA<JSString?>());
+
+  Expect.isTrue(globalContext["u"].isA<JSSymbol?>());
+  Expect.isTrue(globalContext["u"].isA<JSAny?>());
+  Expect.isTrue(globalContext["u"].isA<JSObject?>());
+  Expect.isTrue(globalContext["u"].isA<JSNumber?>());
+  Expect.isTrue(globalContext["u"].isA<JSBoolean?>());
+  Expect.isTrue(globalContext["u"].isA<JSBigInt?>());
+  Expect.isTrue(globalContext["u"].isA<JSString?>());
+}

LibTest/js_interop/JSAnyUtilityExtension/isA_A03_t01.dart

@@ -0,0 +1,43 @@
+// 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 bool isA<T extends JSAny?>()
+/// Whether this [JSAny?] is an instance of the JavaScript type that is declared
+/// by `T`.
+/// ...
+/// If T is a non-primitive JS type like [JSArray] or an interop extension type
+/// on one, this uses an instanceof check using the name or the `@JS` rename of
+/// the given type like `instanceOfString('Array')`. Note that if you rename the
+/// library using the `@JS` annotation, this uses the rename in the instanceof
+/// check like `instanceOfString('library1.JSClass')`.
+///
+/// @description Checks that `isA<JSArray>` returns `true` for `JSArray` type.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../../Utils/expect.dart';
+import '../js_utils.dart';
+
+main() {
+  eval(r'''
+    globalThis.ar1 = Array();
+    globalThis.ar2 = [];
+    globalThis.ar3 = [1, 2, 3];
+  ''');
+  test(globalContext["ar1"]);
+  test(globalContext["ar2"]);
+  test(globalContext["ar3"]);
+}
+
+test(JSAny? value) {
+  Expect.isTrue(value.isA<JSArray>());
+  Expect.isTrue(value.isA<JSAny>());
+  Expect.isTrue(value.isA<JSObject>());
+  Expect.isFalse(value.isA<JSNumber>());
+  Expect.isFalse(value.isA<JSBoolean>());
+  Expect.isFalse(value.isA<JSBigInt>());
+  Expect.isFalse(value.isA<JSString>());
+  Expect.isFalse(value.isA<JSSymbol>());
+}

LibTest/js_interop/JSAnyUtilityExtension/isA_A03_t02.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 bool isA<T extends JSAny?>()
+/// Whether this [JSAny?] is an instance of the JavaScript type that is declared
+/// by `T`.
+/// ...
+/// If T is a non-primitive JS type like [JSArray] or an interop extension type
+/// on one, this uses an instanceof check using the name or the `@JS` rename of
+/// the given type like `instanceOfString('Array')`. Note that if you rename the
+/// library using the `@JS` annotation, this uses the rename in the instanceof
+/// check like `instanceOfString('library1.JSClass')`.
+///
+/// @description Checks that `isA<JSArray>` returns `true` for `JSArray` type.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../../Utils/expect.dart';
+import '../js_utils.dart';
+
+main() {
+  eval(r'''
+    globalThis.ar1 = Array("");
+    globalThis.ar2 = ["one", "two", "three"];
+    globalThis.ar3 = [1, 2, 3];
+  ''');
+  Expect.isTrue(globalContext["ar1"].isA<JSArray<JSString>>());
+  Expect.isTrue(globalContext["ar1"].isA<JSArray<JSObject>>());
+
+  Expect.isTrue(globalContext["ar2"].isA<JSArray<JSString>>());
+  Expect.isTrue(globalContext["ar2"].isA<JSArray<JSNumber>>());
+
+  Expect.isTrue(globalContext["ar3"].isA<JSArray<JSNumber>>());
+  Expect.isTrue(globalContext["ar3"].isA<JSArray<JSString>>());
+}

LibTest/js_interop/JSAnyUtilityExtension/isA_A03_t03.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.
+
+/// @assertion bool isA<T extends JSAny?>()
+/// Whether this [JSAny?] is an instance of the JavaScript type that is declared
+/// by `T`.
+/// ...
+/// If T is a non-primitive JS type like [JSArray] or an interop extension type
+/// on one, this uses an instanceof check using the name or the `@JS` rename of
+/// the given type like `instanceOfString('Array')`. Note that if you rename the
+/// library using the `@JS` annotation, this uses the rename in the instanceof
+/// check like `instanceOfString('library1.JSClass')`.
+///
+/// @description Checks that `isA<JSArray>` returns `true` for an extension type
+/// on `JSArray`.
+/// @author [email protected]
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+import '../../../Utils/expect.dart';
+import '../js_utils.dart';
+
+@JS()
+extension type MyArray1(JSArray ar) implements JSArray {}
+
+@JS()
+extension type MyArray2<T extends JSAny?>(JSArray<T> ar) implements JSArray<T> {
+}
+
+main() {
+  MyArray1 ma1 = MyArray1(JSArray());
+  globalContext["ma1"] = ma1;
+  Expect.isTrue(globalContext["ma1"].isA<JSArray>());
+  Expect.isFalse(globalContext["ma1"].isA<JSNumber>());
+  Expect.isFalse(globalContext["ma1"].isA<MyArray1>());
+
+  eval("globalThis.s = 'JS String';");
+  JSString jsS = globalContext["s"] as JSString;
+  JSArray<JSString> jsArr = JSArray<JSString>.withLength(1);
+  jsArr[0] = jsS;
+  MyArray2<JSString> ma2 = MyArray2(jsArr);
+  globalContext["ma2"] = ma2;
+  Expect.isTrue(globalContext["ma2"].isA<JSArray<JSString>>());
+  Expect.isTrue(globalContext["ma2"].isA<JSArray<JSNumber>>());
+  Expect.isFalse(globalContext["ma2"].isA<MyArray2>());
+}