test/built-ins/TypedArray/prototype/reverse/get-length-uses-internal-arraylength.js


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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-%typedarray%.prototype.reverse
description: Get "length" uses internal ArrayLength
info: |
  22.2.3.22 %TypedArray%.prototype.reverse ( )

  %TypedArray%.prototype.reverse is a distinct function that implements the same
  algorithm as Array.prototype.reverse as defined in 22.1.3.21 except that the
  this object's [[ArrayLength]] internal slot is accessed in place of performing
  a [[Get]] of "length".

  22.1.3.21 Array.prototype.reverse ( )

  1. Let O be ? ToObject(this value).
  2. Let len be ? ToLength(? Get(O, "length")).
  ...
includes: [testTypedArray.js]
features: [TypedArray]
---*/

var getCalls = 0;
var desc = {
  get: function getLen() {
    getCalls++;
    return 0;
  }
};

Object.defineProperty(TypedArray.prototype, "length", desc);

testWithTypedArrayConstructors(function(TA, N) {
  var sample = new TA(N([42, 43]));

  Object.defineProperty(TA.prototype, "length", desc);
  Object.defineProperty(sample, "length", desc);

  sample.reverse();

  assert.sameValue(getCalls, 0, "ignores length properties");
});