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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.fill
description: >
  Fills all the elements from a with a custom start index.
info: |
  22.2.3.8 %TypedArray%.prototype.fill (value [ , start [ , end ] ] )

  %TypedArray%.prototype.fill is a distinct function that implements the same
  algorithm as Array.prototype.fill as defined in 22.1.3.6 except that the this
  object's [[ArrayLength]] internal slot is accessed in place of performing a
  [[Get]] of "length". The implementation of the algorithm may be optimized with
  the knowledge that the this value is an object that has a fixed length and
  whose integer indexed properties are not sparse. However, such optimization
  must not introduce any observable changes in the specified behaviour of the
  algorithm.

  ...

  22.1.3.6 Array.prototype.fill (value [ , start [ , end ] ] )

  ...
  4. If relativeStart < 0, let k be max((len + relativeStart), 0); else let k be
  min(relativeStart, len).
  ...
includes: [compareArray.js, testTypedArray.js]
features: [TypedArray]
---*/

testWithTypedArrayConstructors(function(TA, N) {
  assert(
    compareArray(new TA(N([0, 0, 0])).fill(N(8), 1), N([0, 8, 8])),
    "Fill elements from custom start position"
  );

  assert(
    compareArray(new TA(N([0, 0, 0])).fill(N(8), 4), N([0, 0, 0])),
    "start position is never higher than length"
  );

  assert(
    compareArray(new TA(N([0, 0, 0])).fill(N(8), -1), N([0, 0, 8])),
    "start < 0 sets initial position to max((len + relativeStart), 0)"
  );

  assert(
    compareArray(new TA(N([0, 0, 0])).fill(N(8), -5), N([8, 8, 8])),
    "start position is 0 when (len + relativeStart) < 0"
  );
});