mirror of https://github.com/tc39/test262.git
51 lines
1.4 KiB
JavaScript
51 lines
1.4 KiB
JavaScript
// Copyright (C) 2015 the V8 project authors. All rights reserved.
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// This code is governed by the BSD license found in the LICENSE file.
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/*---
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esid: sec-array.from
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es6id: 22.1.2.1
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description: >
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`this` value of mapping function in strict mode (traversed via iterator)
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info: >
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[...]
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2. If mapfn is undefined, let mapping be false.
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3. else
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a. If IsCallable(mapfn) is false, throw a TypeError exception.
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b. If thisArg was supplied, let T be thisArg; else let T be undefined.
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c. Let mapping be true
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[...]
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6. If usingIterator is not undefined, then
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[...]
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g. Repeat
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[...]
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vii. If mapping is true, then
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1. Let mappedValue be Call(mapfn, T, «nextValue, k»).
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features: [Symbol.iterator]
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flags: [onlyStrict]
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---*/
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var thisVals = [];
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var nextResult = { done: false, value: {} };
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var nextNextResult = { done: false, value: {} };
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var mapFn = function() {
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thisVals.push(this);
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};
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var items = {};
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items[Symbol.iterator] = function() {
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return {
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next: function() {
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var result = nextResult;
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nextResult = nextNextResult;
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nextNextResult = { done: true };
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return result;
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}
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};
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};
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Array.from(items, mapFn);
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assert.sameValue(thisVals.length, 2);
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assert.sameValue(thisVals[0], undefined, 'First iteration `this` value');
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assert.sameValue(thisVals[1], undefined, 'Second iteration `this` value');
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