[Fontconfig] FcPatternGet always gives font weight of '0'

[Lawrence D'Oliveiro]

On Mon, 9 Sep 2019 18:11:03 +0200, Lucien Gentis wrote:

>      const char * newFont="Liberation Sans:style=Bold Italic";

...

I think what you are seeing is the difference in the way Fontconfig
interprets different pattern specs. Using my Python binding
<https://github.com/ldo/python_fontconfig>, and recreating what you are
doing:

    >>> f = fc.Pattern.name_parse("Liberation Sans:style=Bold Italic")
    >>> f.get("family", 0)
    ('Liberation Sans', 0)
    >>> f.get("style", 0)
    ('Bold Italic', 0)
    >>> f.get("weight", 0)
    (None, 1)
    >>> f.get("slant", 0)
    (None, 1)

The second number in the result tuples is the status code; the nonzero
value is FcResultNoMatch for the weight and slant. But if I write the
pattern this way:

    >>> f = fc.Pattern.name_parse("Liberation Sans:weight=bold:slant=italic")
    >>> f.get("family", 0)
    ('Liberation Sans', 0)
    >>> f.get("style", 0)
    (None, 1)
    >>> f.get("weight", 0)
    (200.0, 0)
    >>> f.get("slant", 0)
    (100, 0)

Now you see that the pattern has no style property, but it does have a
weight and slant. Because that is what I specified. The first variant
has a style, but no weight or slant, again because that is what I
specified.

Remember, this is just the search pattern. Once you use this to find an
actual font, you should get a lot more info back from the matching
instance pattern.