49 lines
1.1 KiB
JavaScript
49 lines
1.1 KiB
JavaScript
function shouldBe(actual, expected) {
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if (actual !== expected)
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throw new Error('bad value: ' + actual);
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}
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class DerivedArray extends Array {
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get 2() {
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this.called = true;
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return 42;
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}
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}
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{
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let array = [];
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array.__proto__ = DerivedArray.prototype;
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array.length = 42;
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shouldBe(array.lastIndexOf(42), 2);
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shouldBe(array.called, true);
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}
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{
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let array = [20, 20];
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array.__proto__ = DerivedArray.prototype;
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array.length = 42;
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shouldBe(array.lastIndexOf(42), 2);
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shouldBe(array.called, true);
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}
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{
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let array = ["Hello"];
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array.__proto__ = DerivedArray.prototype;
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array.length = 42;
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shouldBe(array.lastIndexOf(42), 2);
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shouldBe(array.called, true);
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}
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{
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let array = [42.195];
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array.__proto__ = DerivedArray.prototype;
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array.length = 42;
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shouldBe(array.lastIndexOf(42), 2);
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shouldBe(array.called, true);
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}
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{
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let array = ["Hello"];
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array.__proto__ = DerivedArray.prototype;
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array.length = 42;
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ensureArrayStorage(array);
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shouldBe(array.lastIndexOf(42), 2);
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shouldBe(array.called, true);
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}
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