[webkit-qt] About the fonts used for QtWebKit tests

[Caio Marcelo de Oliveira Filho]

Hello folks,

Disclaimer: I'm not a font expert, I just want to make an editing
layout test to pass in Qt port, and it happens to depend on monospace
fonts. :]

Last week I've hacked a bit our font infrastructure in testing. I've
found out that the current state is not good: we have two odd
configuration files with a lot of indirection and unused information,
and we also have with problems like not getting monospace font when
tests asks for those fonts. This naturally cause some tests that
depend the fixed size of the characters to fail, for example
https://bugs.webkit.org/show_bug.cgi?id=50144.

After talking to elproxy and bbandix, I made a new configuration file
(and corresponding changes for QtWebKit), tested by me in Qt 4.8, 5.0
and 5.0-wk2 and also some tests by bbandix, that seems to do the right
thing. The patches are here
https://bugs.webkit.org/show_bug.cgi?id=85203 for you guys to take a
look and review.

The problem is: this change means we need to do a big rebaseline of
~5000 tests (also listed in the previous patch). Not only monospace
fonts changed but also some fonts that previously were wrongly
assigned to our sans-serif, are now properly assigned to our serif
font. Note that even though we have some pixel tests, not all of them
matches the actual results even without the patch.

Brings me to question

1) How we handle such a big rebaseline? How you guys did before?

- One person do it in a big rebaseline (I'm not very enthusiastic with
this approach, although the rebasilne server tool seems very good).
- Skip all those tests (in a separated section in the Skipped file)
and "crowdsource" the work of rebaselining.
- Another way?


And since we are doing this rebaseline, another question...

2) Given that we have a huge rebaseline ahead, what about changing our
Nimbus family of fonts to the Liberation family of fonts
(http://en.wikipedia.org/wiki/Liberation_fonts). I see two benefits:

- They share the metrics with the Arial/TimesNewRoman/CourierNew
fonts, so we could _potentially_ share some expected results with
other ports.
- And even if we don't, the results at least will look similar, making
our and other port developer life easier when assessing a patch and
doing a rebaseline.

Note that these fonts are not to be distributed with Qt, just used by
developers and robots. We can keep our version of them in
testfonts.git.


Long story short:
(1) How we do this rebaseline?
(2) Let's use the opportunity to migrate to Liberation family?


Cheers,

-- 
Caio Marcelo de Oliveira Filho
openBossa @ INdT - Instituto Nokia de Tecnologia