[webkit-changes] [WebKit/WebKit] 58d1ff: [CSS Math Functions] round() is incorrect when num...

[Tim Nguyen]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 58d1ff825f4e6920efe7fe6a8762d8c84cedf76e
      https://github.com/WebKit/WebKit/commit/58d1ff825f4e6920efe7fe6a8762d8c84cedf76e
  Author: Tim Nguyen <ntim at apple.com>
  Date:   2023-08-01 (Tue, 01 Aug 2023)

  Changed paths:
    M LayoutTests/imported/w3c/web-platform-tests/css/css-values/round-mod-rem-computed-expected.txt
    M LayoutTests/imported/w3c/web-platform-tests/css/css-values/round-mod-rem-computed.html
    M Source/WebCore/platform/calc/CalcOperator.h

  Log Message:
  -----------
  [CSS Math Functions] round() is incorrect when number is a multiple of step
https://bugs.webkit.org/show_bug.cgi?id=259702
rdar://113233588

Reviewed by Simon Fraser.

In Safari 16.6, round(up, 10px, 5px) resolves to 15px instead of 10px as it should.

>From https://drafts.csswg.org/css-values-4/#round-func:
> If A is exactly equal to an integer multiple of B, round() resolves to A exactly

Also add WPT for https://drafts.csswg.org/css-values/#round-infinities

* LayoutTests/imported/w3c/web-platform-tests/css/css-values/round-mod-rem-computed-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/css/css-values/round-mod-rem-computed.html:
* Source/WebCore/platform/calc/CalcOperator.h:
(WebCore::evaluateCalcExpression):

Canonical link: https://commits.webkit.org/266504@main