401046 - minimum font-size preference should not affect font-size:0 (zero)

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, defect)

Description

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

The minimum font-size preference currently increases font sizes specified as 0 to the minimum.  However, the purpose of this preference is to make text that's too small to be readable for the user readable.  However, designers (and, probably more often, testcase authors) sometimes use font-size:0 as a trick to hide things.  Since, in this case, the text is intended not to be readable, I think the pref should not change font sizes that are zero.

Steps to reproduce:
  1. set minimum font size preference in Preferences/Options -> Content -> Fonts & Colors -> Advanced -> Western
  2. load
http://mxr.mozilla.org/seamonkey/source/layout/reftests/z-index/z-index-1.html

Expected results: all colored boxes have the same top and bottom
Actual results: some colored boxes displaced vertically

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: patch

Here's the trivial patch.  I should write tests for this pref sometime, including this fix.

And the steps to reproduce above aren't accurate -- this alone doesn't fix that test for me.  (Not sure how it's passing on tinderbox, then.)

Comment 2

[Hixie (not reading bugmail)]

I'd also say that the minimum font-size pref shouldn't kick in until there's actual text to render. font-size: 0 is useful as a way to guarantee the placement of a baseline, even in the absence of text (e.g. for placing inline-block boxes, as in Acid3).

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: patch

Here's the same trivial patch, with test.

I really need to file a bug on making the language-sensitivity of our font prefs use something better than the charset...

Comment 4

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 302171 [details] [diff] [review]
patch

Document that the setTimeout(setTimeout,...) thing is being used to handle the async pref changes, and r+sr=bzbarsky

Comment 5

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Comment on attachment 302171 [details] [diff] [review]
patch

Trivial fix that makes it easier to use a bunch of Hixie's tests (and some others), and improves things for authors/users as well.

Comment 6

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Checked in to trunk, 2008-02-09 11:15 -0800.

Comment 7

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

...and filed bug 416581 on better font preference language handling.