js/src/tests/ecma_6/Math/fround.js@129ffea94266 (annotated)
js/src/tests/ecma_6/Math/fround.js
Sat, 03 Jan 2015 20:18:00 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Sat, 03 Jan 2015 20:18:00 +0100
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
- permissions
- -rw-r--r--
Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.
| michael@0 | 1 | /* |
| michael@0 | 2 | * Any copyright is dedicated to the Public Domain. |
| michael@0 | 3 | * http://creativecommons.org/licenses/publicdomain/ |
| michael@0 | 4 | */ |
| michael@0 | 5 | |
| michael@0 | 6 | // Some tests regarding conversion to Float32 |
| michael@0 | 7 | assertEq(Math.fround(), NaN); |
| michael@0 | 8 | |
| michael@0 | 9 | // Special values |
| michael@0 | 10 | assertEq(Math.fround(NaN), NaN); |
| michael@0 | 11 | assertEq(Math.fround(-Infinity), -Infinity); |
| michael@0 | 12 | assertEq(Math.fround(Infinity), Infinity); |
| michael@0 | 13 | assertEq(Math.fround(-0), -0); |
| michael@0 | 14 | assertEq(Math.fround(+0), +0); |
| michael@0 | 15 | |
| michael@0 | 16 | // Polyfill function for Float32 conversion |
| michael@0 | 17 | var toFloat32 = (function() { |
| michael@0 | 18 | var f32 = new Float32Array(1); |
| michael@0 | 19 | function f(x) { |
| michael@0 | 20 | f32[0] = x; |
| michael@0 | 21 | return f32[0]; |
| michael@0 | 22 | } |
| michael@0 | 23 | return f; |
| michael@0 | 24 | })(); |
| michael@0 | 25 | |
| michael@0 | 26 | // A test on a certain range of numbers, including big numbers, so that |
| michael@0 | 27 | // we get a loss in precision for some of them. |
| michael@0 | 28 | for (var i = 0; i < 64; ++i) { |
| michael@0 | 29 | var p = Math.pow(2, i) + 1; |
| michael@0 | 30 | assertEq(Math.fround(p), toFloat32(p)); |
| michael@0 | 31 | assertEq(Math.fround(-p), toFloat32(-p)); |
| michael@0 | 32 | } |
| michael@0 | 33 | |
| michael@0 | 34 | /******************************************** |
| michael@0 | 35 | /* Tests on maximal Float32 / Double values * |
| michael@0 | 36 | /*******************************************/ |
| michael@0 | 37 | function maxValue(exponentWidth, significandWidth) { |
| michael@0 | 38 | var n = 0; |
| michael@0 | 39 | var maxExp = Math.pow(2, exponentWidth - 1) - 1; |
| michael@0 | 40 | for (var i = significandWidth; i >= 0; i--) |
| michael@0 | 41 | n += Math.pow(2, maxExp - i); |
| michael@0 | 42 | return n; |
| michael@0 | 43 | } |
| michael@0 | 44 | |
| michael@0 | 45 | var DBL_MAX = maxValue(11, 52); |
| michael@0 | 46 | assertEq(DBL_MAX, Number.MAX_VALUE); // sanity check |
| michael@0 | 47 | |
| michael@0 | 48 | // Finite as a double, too big for a float |
| michael@0 | 49 | assertEq(Math.fround(DBL_MAX), Infinity); |
| michael@0 | 50 | |
| michael@0 | 51 | var FLT_MAX = maxValue(8, 23); |
| michael@0 | 52 | assertEq(Math.fround(FLT_MAX), FLT_MAX); |
| michael@0 | 53 | assertEq(Math.fround(FLT_MAX + Math.pow(2, Math.pow(2, 8 - 1) - 1 - 23 - 2)), FLT_MAX); // round-nearest rounds down to FLT_MAX |
| michael@0 | 54 | assertEq(Math.fround(FLT_MAX + Math.pow(2, Math.pow(2, 8 - 1) - 1 - 23 - 1)), Infinity); // no longer rounds down to FLT_MAX |
| michael@0 | 55 | |
| michael@0 | 56 | /********************************************************* |
| michael@0 | 57 | /******* Tests on denormalizations and roundings ********* |
| michael@0 | 58 | /********************************************************/ |
| michael@0 | 59 | |
| michael@0 | 60 | function minValue(exponentWidth, significandWidth) { |
| michael@0 | 61 | return Math.pow(2, -(Math.pow(2, exponentWidth - 1) - 2) - significandWidth); |
| michael@0 | 62 | } |
| michael@0 | 63 | |
| michael@0 | 64 | var DBL_MIN = Math.pow(2, -1074); |
| michael@0 | 65 | assertEq(DBL_MIN, Number.MIN_VALUE); // sanity check |
| michael@0 | 66 | |
| michael@0 | 67 | // Too small for a float |
| michael@0 | 68 | assertEq(Math.fround(DBL_MIN), 0); |
| michael@0 | 69 | |
| michael@0 | 70 | var FLT_MIN = minValue(8, 23); |
| michael@0 | 71 | assertEq(Math.fround(FLT_MIN), FLT_MIN); |
| michael@0 | 72 | |
| michael@0 | 73 | assertEq(Math.fround(FLT_MIN / 2), 0); // halfway, round-nearest rounds down to 0 (even) |
| michael@0 | 74 | assertEq(Math.fround(FLT_MIN / 2 + Math.pow(2, -202)), FLT_MIN); // first double > FLT_MIN / 2, rounds up to FLT_MIN |
| michael@0 | 75 | |
| michael@0 | 76 | assertEq(Math.fround(-FLT_MIN), -FLT_MIN); |
| michael@0 | 77 | |
| michael@0 | 78 | assertEq(Math.fround(-FLT_MIN / 2), -0); // halfway, round-nearest rounds up to -0 (even) |
| michael@0 | 79 | assertEq(Math.fround(-FLT_MIN / 2 - Math.pow(2, -202)), -FLT_MIN); // first double < -FLT_MIN / 2, rounds down to -FLT_MIN |
| michael@0 | 80 | |
| michael@0 | 81 | reportCompare(0, 0, "ok"); |
