JSTests/test262/test/built-ins/String/prototype/charAt/pos-rounding.js

// 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-string.prototype.charat
es6id: 21.1.3.1
description: Rounding of the provided "pos" number
info: |
  [...]
  3. Let position be ? ToInteger(pos).
  [...]

  7.1.4 ToInteger

  1. Let number be ? ToNumber(argument).
  2. If number is NaN, return +0.
  3. If number is +0, -0, +∞, or -∞, return number.
  4. Return the number value that is the same sign as number and whose
     magnitude is floor(abs(number)). 
---*/

assert.sameValue('abc'.charAt(-0.99999), 'a', '-0.99999');
assert.sameValue('abc'.charAt(-0.00001), 'a', '-0.00001');
assert.sameValue('abc'.charAt(0.00001), 'a', '0.00001');
assert.sameValue('abc'.charAt(0.99999), 'a', '0.99999');
assert.sameValue('abc'.charAt(1.00001), 'b', '1.00001');
assert.sameValue('abc'.charAt(1.99999), 'b', '1.99999');