src/v8/test/mjsunit/compiler/typedarray-prototype-tostringtag.js

// Copyright 2017 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Flags: --allow-natives-syntax

const Classes = [
  Uint8Array,
  Int8Array,
  Uint16Array,
  Int16Array,
  Uint32Array,
  Int32Array,
  Uint8ClampedArray,
  Float32Array,
  Float64Array
];
const TypedArrayPrototype_toStringTag =
    Object.getOwnPropertyDescriptor(
        Object.getPrototypeOf(Uint8Array.prototype),
        Symbol.toStringTag).get;

(function() {
  function foo(o) {
    return TypedArrayPrototype_toStringTag.call(o);
  }
  assertEquals(undefined, foo(1));
  assertEquals(undefined, foo({}));
  assertEquals(undefined, foo([]));
  Classes.forEach(C => assertEquals(C.name, foo(new C(1))));
  %OptimizeFunctionOnNextCall(foo);
  assertEquals(undefined, foo(1));
  assertEquals(undefined, foo({}));
  assertEquals(undefined, foo([]));
  Classes.forEach(C => assertEquals(C.name, foo(new C(1))));
})();

(function() {
  const ReflectApply = Reflect.apply;
  const uncurryThis = func => (thisArg, ...args) =>
      ReflectApply(func, thisArg, args);
  const TypedArrayProto_toStringTag =
      uncurryThis(TypedArrayPrototype_toStringTag);

  function isTypedArray(value) {
    return TypedArrayProto_toStringTag(value) !== undefined;
  }

  assertFalse(isTypedArray(1));
  assertFalse(isTypedArray({}));
  assertFalse(isTypedArray([]));
  assertFalse(isTypedArray('Lorem ipsum'));
  Classes.forEach(C => assertTrue(isTypedArray(new C(1))));
  %OptimizeFunctionOnNextCall(isTypedArray);
  assertFalse(isTypedArray(1));
  assertFalse(isTypedArray({}));
  assertFalse(isTypedArray([]));
  assertFalse(isTypedArray('Lorem ipsum'));
  Classes.forEach(C => assertTrue(isTypedArray(new C(1))));
})();

(function() {
  const ReflectApply = Reflect.apply;
  const uncurryThis = func => (thisArg, ...args) =>
      ReflectApply(func, thisArg, args);
  const TypedArrayProto_toStringTag =
      uncurryThis(TypedArrayPrototype_toStringTag);

  function isUint8Array(value) {
    return TypedArrayProto_toStringTag(value) === 'Uint8Array';
  }

  assertFalse(isUint8Array(1));
  assertFalse(isUint8Array({}));
  assertFalse(isUint8Array([]));
  assertFalse(isUint8Array('Lorem ipsum'));
  Classes.forEach(C => assertEquals(C === Uint8Array, isUint8Array(new C(1))));
  %OptimizeFunctionOnNextCall(isUint8Array);
  assertFalse(isUint8Array(1));
  assertFalse(isUint8Array({}));
  assertFalse(isUint8Array([]));
  assertFalse(isUint8Array('Lorem ipsum'));
  Classes.forEach(C => assertEquals(C === Uint8Array, isUint8Array(new C(1))));
})();