This was added by 9ff76c27b9 on
the basis that it signifies a shaping error and would later assert
or crash.
But the line is easily reachable by user code. If Harfbuzz returns
0 glyphs, it just means it is unable to shape the string, for instance
if the input string only contains default ignorables (like a ZWJ)
and does not have any appropriate glyph to use for replacement.
Qt expects there to always be at least one glyph in the output
(num_glyphs == 0 is used to indicate shaping is not yet done), so
to avoid asserts later on, we simply populate the output with a
single 0 token, which is a required entry in the font that is
reserved for representing unrepresentable characters.
This also adds a test and therefore a zero-width joiner to the test
font to reproduce the issue.
[ChangeLog][QtGui][Text] Fixed a possible crash with certain fonts
when shaping strings consisting only of control characters.
Fixes: QTBUG-89155
Pick-to: 5.15
Pick-to: 6.0
Change-Id: Ia0dd6a04844c9be90dcab6c464bebe339a3dab11
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
The sample lineedit in Qt's own font dialog shouldn't have its font
affected by stylesheets.
Not only does this hampers the ability to preview the font, it actually
overrides the font selection as that one is taken directly from the
widget.
Task-number: QTBUG-41513
Change-Id: I11d0bef8c7bf7bdae4cc08b6b9276d0fc14a75fb
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@theqtcompany.com>
Eskil Abrahamsen Blomfeldt
Pierre Rossi