539925 - fix a few reftest fragility issues

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[Jonathan Kew [:jfkthame]]

I've been seeing some reftests consistently fail locally on OS X, even though they're passing on Tinderbox. This is caused by subpixel antialiasing and painting issues; I found that if I disable the "Use LCD font smoothing" option in System Preferences / Appearance, the failures go away. But it would be good to make the tests less sensitive to such settings, which are not relevant to the specific issues being tested.

(1) with-first-letter-2 can fail because an antialiased pixel from one of the Hebrew glyphs overlaps the adjacent text run. To avoid this, I've changed the Hebrew letters used so as to avoid the Gimel glyph with its tip that extends very close to the nominal edge of the bounding box.

(2) bugs/296361-1 fails because of antialiasing from the serifs of the first letter projecting to the left of the text origin. To avoid this, I've specified the use of sans-serif. (Also removed CRLF line endings from the test files.)

(3) the text/line-editing-* tests fail similarly because of an antialiasing pixel that doesn't get refreshed properly when the text changes; solved by adding a couple of pixels of padding.

Cases (2) and (3) should be resolved properly when we handle ink overflow properly, and fix bugs 475968 and 476927.

Comment 1

[Jonathan Kew [:jfkthame]]

Attachment: make reftests more robust, as per description

Comment 2

[Jonathan Kew [:jfkthame]]

Pushed http://hg.mozilla.org/mozilla-central/rev/c45600325135