bug#16721: 24.3.50; can not use ext font anymore

[K. Handa]

In article <87eh37f0qy.fsf@tao.kanis.fr>, Ivan Kanis <ivan@kanis.fr> writes:

> "-unknown-Symbola-normal-normal-semi-condensed-*-20-*-*-*-0-iso10646-1"

> Gives me a Font Error. I count 14 elements.

Emacs' XLFD parser is stricter than the spec of XLFD.  For
instance, the possible value of SETWIDTH_NAME field (the 5th
one) is one of:
  undefined ultracondensed extracondensed condensed
  semicondensed medium semiexpanded expanded extraexpanded
  ultraexpanded
which are "english translation"s of defined reference value
for RELATIVE_SETWIDTH property.  See:
  
http://www.x.org/releases/X11R7.6/doc/xorg-docs/specs/XLFD/xlfd.html#font_properties

So, in the above case, Emacs thinks "semi" is not a valid
SETWIDTH_NAME of a font.

This strictness is to handle a wildcard "*" matching with
multiple fields efficently.  For instance, to find a font
matching with "*-bold-*", Emacs assumes that "bold" is for
WEIGHT_NAME field, and lists fonts whose WEIGHT_NAME field
is "bold".  This is far faster than getting all font names
and check each of them whether it contains "bold" or not.

> The font
> "xft:-unknown-Symbola-normal-normal-semi-condensed-*-20-*-*-*-*-0-iso10646-1"
> Is a copy & paste of what emacs 24.3 report after doing a C-u C-x =

Yes, it's a bug, and should be fixed already.

---
Kenichi Handa
handa@gnu.org