Refactors feaLib, moving code which builds OpenType lookups into otlLib. Note that this changes feaLib's concept of `location` from a tuple to an object.
This makes the directory to search for included files explicit.
Also use Python 3's FileNotFoundError to catch non-existant files instead of a workaround for Python 2.
This allows for more than one "lookup ..." chaining statements at each glyph position in a chaining contextual substitution or positioning rule: e.g.
sub a b c' lookup lookup1 lookup lookup2 d;
The corresponding change in the Adobe OpenType Feature File Specification (and implementation in makeotf) happened in adobe-type-tools/afdko#1132.
Support was added in db49f20d6b2629e1ba25c4afd3fb60817387f3d6, but there
was only a parser test and no builder test, fix the build and add a
builder test based on the existing parser one.
Fixes https://github.com/fonttools/fonttools/issues/1901
Raise if lookup_index is None, which would happen only of the lookup
referenced belongs to the wrong table. The error message needs to be less
cryptic, though.
Fixes https://github.com/fonttools/fonttools/issues/1896
Setting script that is the same as current language system should make
no effect. This is not documented in the spec, but it is what makeotf
does. This as the effect of preserving lookupflag when set before such a
script statement.
Fixes https://github.com/fonttools/fonttools/issues/1824
This checks that glyph names that appear in a feature file are actually
in the glyph set provided in glyphNames. If the set is empty, no check
is done. This preempts a KeyError later during saving of a TTFont object
and makes this case much more easily catchable.
Closes#1723.
On Windows, tests may be run in the user's temp directory, so the previous code
may compare C:\Users\nikolaus.waxweiler\ against C:\Users\NIKOLA~1.WAX\.
If the single substitution involved a glyph class, we were incorrectly
using only the first glyph in the class.
Broken since ec6ff821f0e72022d7aec8794b6bb589d8f81808, apparently no one
else uses this feature!
The code tries to write the short format when some values as None, but
when writing the long format it would write any None value as is which
is invalid, use 0 for None values instead.
Allow for making more lookups support subtabe breaks. Although AFDKO’s
makeotf supports subtable breaks only in pair pos lookups, I believe
that is an implementation limit that we don’t have to follow; all
OpenType lookups has subtables and it should be possible to code that in
the feature files.
