- From: Håkon Wium Lie <howcome@opera.com>
- Date: Wed, 3 Jul 2013 02:01:52 +0200
- To: =?iso-8859-1?Q?"G\=E9rard\?\= Talbot" <css21testsuite@gtalbot.org>
- Cc: "Public CSS Testsuite mailing list" <public-css-testsuite@w3.org>
Hello Gérard, > [nightly-unstable] > http://test.csswg.org/suites/css3-multicol/nightly-unstable/html4/multicol-margin-001.htm > > [src] > http://test.csswg.org/source/contributors/opera/submitted/multicol/multicol-margin-001.xht > > As far as I can understand, this test is supposed to be verifying that > the top margin of the first block child element of a multicol element > does not collapse with the top margin of the multicol element. Correct. > line 11: body { > margin: 0; > } > line 14: p { > border-bottom: 2em solid white; > margin-bottom: 1em; > } > > These rules are not part of the test itself. The <p> has no content > anyway in this non-self-describing test. > We usually prefer to use/rely on browser defaults for body margins and p > margins. This way, tests can be shorter and more straightforward and > they also will work on browsers with different body margins and p > margins. > There is no need in such tests for resetting those (body and p) margins. Agree, they should be removed. > line 19: font-family: ahem; > line 20: font-size: 1em; > > Whenever the Ahem font is used, we need to set a font-size whose > computed value will be dividable by 5px without a remainer. We do this > to avoid rounding issues and to ensure accurate vertical positioning of > content on the baseline, mostly for the Linux platform. > > " > If the test uses the Ahem font, make sure its computed font-size is a > multiple of 5px, otherwise baseline alignment may be rendered > inconsistently (due to rounding errors introduced by certain platforms' > font APIs). We suggest to use a minimum computed font-size of 20px. > " > http://wiki.csswg.org/test/format#acceptable-test-formats > > And so its current associated reftest would need to be updated to > reflect this too. So, you suggest setting?: div { font-size: 20px } I still seee vertical lime stripes on my Linux screen. But that may be something else? > All the multi-column tests submitted by Opera will need to be adjusted > on this font-size of Ahem font issue. Noted. Thanks for pointing this out. I'll try go through them. > line 26: position: relative; > line 37: div::after { > content: ""; > background: white; > height: 1em; > width: 2em; > position: absolute; > right: 0; > bottom: 0; > display: block; > line 46: } > > I do not see the reason for the generated 2x1 white rectangle in the > test. If margin-top of first child collapses with the margin-top of the > multi-column element, then we will see a bright green > 32px-wide-by-16px-tall rectangle at the bottom right corner. If > margin-top of first child does *not* collapse with the margin-top of the > multi-column element, then we should see such bright green > 32px-wide-by-16px-tall rectangle at the top left corner. And so, the > comparison with the reftest should work by itself; the lime stripes > position and dimension would need to be identical. > > So, I think that the div::after rule is not needed, not required in the > test and that line 26 is also not needed, not necessary. Your analysis seems right to me; I don't know why the white rectangle was there. > As is, the test is still a correct one but it's imprecise, not > straightforward, streamlined. Thanks for your detailed analysis. I'll update the test in the repository once I hear back about the font size. BTW, I'm also working my way through the tests -- here are my sketchy notes on conformance: http://people.opera.com/howcome/2013/tests/multicol-table.html There are two good implemenetations that should help us through to PR. I'll need help in having the tests reviewed, though -- I can't review tests submitted by Opera, I believe. Cheers, -h&kon Håkon Wium Lie CTO °þe®ª howcome@opera.com http://people.opera.com/howcome
Received on Wednesday, 3 July 2013 00:02:40 UTC