The code that is being removed is untested and does not seem to make
fixing an overflow any easier. The fixer code just needs to know
which subtable caused the overflow and does not care about the item
within. As such, no point in trying to find a "right" item.
In fact, leaving item as is, is more useful in debugging overflows
as it reflects which item's offset actually overflowed.
Part of fixing https://github.com/behdad/fonttools/issues/537
According to the spec:
> The lookupflag attribute defaults to 0 at the start of a feature
> block.
>
> The lookupflag attribute stays the same until explicitly changed, until
> a lookup reference statement is encountered that changes it, until the
> script is changed, or until the end of the feature.
This is an attempt to fix this by resetting the lookupflag at the start
and end of feature/lookup blacks. I’m not sure if resetting it in lookup
blocks is correct (my reading of the spec suggests it is not), but one
needs to test this against makeotf and see how it behaves here.
otherwise `not NotImplemented` (always False) is returned from __ne__ when `type(self) != type(other)`, leading to illogic results like:
>>> from fontTools.ttLib.tables.DefaultTable import DefaultTable
>>> t = DefaultTable('test')
>>> t == 0
False
>>> t != 0
False
The latter of course should return True.
previously assertEqual would fail, despite the `program` attributes where both empty, as the object have different id(). The Program.__eq__ method now compares self.__dict__ == other.__dict__, hence the test pass.
Unlike simple glyphs (with contours) which must always have `instructionLength`, the field is optional in composite glyphs and depends on whether `WE_HAVE_INSTR` flag is set:
https://www.microsoft.com/typography/otspec/glyf.htm
In the previous code, the TTGlyphPen was adding an empty `program` attribute to any new glyph, including composite glyphs. It should only do it for simple glyphs.
For example, if you take Roboto-Regular.ttf from here:
https://github.com/google/roboto/releases/tag/v2.129
The font (unhinted) was compiled using the ttGlyphPen. It has 1434 composite glyphs. For each of them, a USHORT value for the number of instructions (0) is written, so the binary ttf is 2.868 KB greater than
what it should be.
Apparently string slices are not as smart as I was hoping for.
Slicing a looong (say, 1MB) string and holding onto it is not a
good idea if done thousands of times. So, do fewer slicings and
decompile subtables immediately instead of holding onto data.
This makes me want to rethink the kind of data structures we use
for lazy processing.
Fixes https://github.com/behdad/fonttools/issues/317
In the long term, we might want to make a different low-level API
for building ChainContextPos lookups; for now, this should fix the
current bug with SequenceIndex.
Resolves https://github.com/behdad/fonttools/issues/517.
There should be no semantic difference from this change,
since dependent lookups (the chain targets) are never directly
invoked by a feature. But the output of feaLib becomes more
similar to the output of makeotf, which helps debugging.
Before this change, we had only emitted a SinglePos (GPOS type 1) lookup
for a statement like `pos A' B' 20`; after this change, we always emit a
chain rule even if there is no context. There is a semantic difference if
the rule is preceded by a `ignore pos` statement. Omitting context-free
contextual chains was actually not a (premature) optimization, but an
artifact that came from the representation of glyph patterns.
https://github.com/behdad/fonttools/issues/516
After this change, feaLib generates the exact same output as makeotf
for the test case in `bug453.fea`. Before this change, feaLib had
rejected the input as malformed.
Our new behavior is in blatant violation of the OpenType Feature File
Syntax specification, which writes: "NOTE! If a GDEF table is not
explicitly defined in the feature file, [...] all mark glyph classes
must be disjoint". However:
1. makeotf does not enforce this constraint;
2. existing feature files happily define non-disjoint markClasses;
3. existing tools such as the Glyphs font editor generate feature files
with non-disjoint markClasses;
4. it is not obvious what the intention of this constraint would be.
Therefore, fewLib now follows the makeotf implementation, intentionally
ignoring what is mandated by the specification. I've proposed a spec change
at https://github.com/adobe-type-tools/afdko/issues/106.
Resolves https://github.com/behdad/fonttools/issues/453.
The glob pattern determines which classes are considered for test collection by pytest.
We already follow this pattern for the unittest.TestCase derived subclasses
(which are collected regardless of this option).
