This patch ensures that feaLib always produces a name table with entries
sorted in the order proscribed by the spec: platform id, encoding id,
language id, name id.
This breaks some tests, and so I have manually updated the test data to
match the new outputs.
* add test that fails for #2293
* fixing #2293: rewrite of contextual positioning logic, ensure len(suffix) > 1 yields the correct result; checking more edge cases and raising errors inspired by makeotf
* test error cases
* only check when we actually have a value
* catch one more case that makeotf errors on and we didn't
* Replaced all from ...py23 import * with explicit name imports, or removed completely when possible.
* Replaced tounicode() with tostr()
* Changed all BytesIO ans StringIO imports to from io import ..., replaced all UnicodeIO with StringIO.
* Replaced all unichr() with chr()
* Misc minor tweaks and fixes
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
