208479 - Add Unicode 'char' to langGroup mapping

Status: NEW

(Core :: Internationalization, defect)

Description

[Jungshik Shin]

Currently, GFX:GTK (both X11core, Xft) used  fonts configured for the langGroup
of the current locale when rendering Unicode documents without lang (html) and
xml:lang (xml) specified. For instance, Tamil pages in UTF-8 without
lang/xml:lang specified are rendered with fonts configured for Tamil (x-tamil
langgroup) under 'ta-IN' locale. However, under 'en-US' locale, Tamil pages in
UTF-8 are rendered with fonts configured for x-western langgroup. 

GFX:Win infers langGroup from the code range so that regardless of the current
locale, Tamil pages are always rendered with fonts configured for Tamil
(x-tamil) langGroup. (see bug 206123).

We need to move up a couple of related files[1] in gfx/src/win to gfx/src/shared
(or perhaps intl/locale [2] ) to share the code in GFX:Win used to map the code
range to langGroup. (bug 206123)

[1]
http://lxr.mozilla.org/seamonkey/source/gfx/src/windows/nsUnicodeRange.cpp

[2] If mapping code points to langGroup turns out to be useful outside GFX, we'd
better put this somewhere in intl. In that case, platform should be 'All'.

Comment 1

[rbs]

I vote for [2].

This mapping is pretty generic and has little to do with platform specific stuff.

Comment 2

[Jungshik Shin]

I agree with rbs and am changing the summary line. It seems like we have to add
a method to nsILanguageAtomService [1] that returns 'langGroup' given a Unicode
character (and possibly a Unicode range).

[1]
http://lxr.mozilla.org/seamonkey/source/intl/locale/idl/nsILanguageAtomService.idl

Comment 3

[Jungshik Shin]

This is also useful when NCRs are used to represent characters not covered by
the current document encoding. For instance, an ISO-8859-1 document can be used
to represent any Unicode character. So, our fallback of inferring 'langGroup'
from the page encoding completely breaks down in that case.

Comment 4

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee didn't login in Bugzilla in the last 7 months, so the assignee is being reset.