The current argument parser in subset.py must strip out spaces in values,
in order to allow specifying comma- or whitespace-separated lists (for
example, cf. [line 2289](https://github.com/behdad/fonttools/blob/master/Lib/fontTools/subset.py#L2289))
Because of that, users cannot correctly specify table tags whose length
is less than 4 by enclosing the space in quotes.
For example, 'SVG ' table will be alwyas dropped even if I pass
`--drop-tables-='SVG '` and `--no-subset-tables+='SVG '`.
As a workaround, this patch removes the spaces from the 'SVG ' and 'cvt '
tags in the constant lists of the Option class, and it only tests that
`tag.strip()` is contained in those list.
Of course, this also means `--drop-tables-='SVG '` is now the same as
`--drop-tables-='SVG' as far as the subsetter is concerned.
Fixes https://github.com/behdad/fonttools/issues/376
Related https://github.com/behdad/fonttools/issues/265
This should make the unit tests more readable, and it also prevents
failures where a changed fromXML() implementation fails to ignore
interspersed whitespace. This has recently caused some developer
nuisance; see https://github.com/behdad/fonttools/pull/367.
Instead of having a custom parser implementation, it would be nicer
to call the actual XMLReader. However, XMLReader has a deeply built-in
assumption that it is processing an entire TTX file. Changing this
assumption would certainly be possible, but it would need a re-write
of the XMLReader code; having a custom parser just for unit tests
seems less involved.
Resolves https://github.com/behdad/fonttools/issues/355
For making sure that `pyftsubset` still works after this change,
I have done the following steps:
* invoked Adobe's `makeotf` tool to build a custom font with a
MultipleSubst lookup. This lookup decomposes two two ligatures,
`c_t` and `f_f_i`, into their respective components.
* invoked the `pyftsubset` tool to produce a subset font with just
the `c_t` ligature;
* checked with `ttx` that the newly produced subset font contains
the requested `c_t` ligature and its components `c` and `t`,
but does not contain not any of `f_f_i`, `f`, or `i`.
Before this change, TTX (when running in Python 2.7) would fail
to compile a font if the input contained an `ltag` section.
With Python 3, it worked perfectly fine even before this change.
Resolves https://github.com/behdad/fonttools/issues/357
The list of subtables should go in the 'SubTable' attribute of Lookup object.
This also sets the 'LookupType', 'LookupFlag' and 'SubTableCount' attributes.
Using TTFont.getGlyphOrder() would also require to decompile post and cmap tables.
But we don't need the actual glyph names in order to apply the WOFF2 glyf transform.
An earlier change made sure that language tags would always be
four characters in length, even when ending in whitespace.
This made a few test cases in parser_test.py fail. By accident,
I had only run builder_test (instead of all unittest in fonttools)
before committing that change.
Currently, the compiler uses them to figure out which set of
languagesystems would apply for the current scope. However, this
information is not yet used for anything.
Also add ';' to some langaugesystem test cases. This makes the
snippets syntactically valid. The parser is still expected to
reject them for other reasons, just as before this change.
This simplifies the public API to the library. For clients, it does
not matter which exact component was detecting an error. And we will
soon have more components; there would be little point in declaring
CompilerError, TableBuilderError, and so forth.
Before this change, the XML output for GSUB lookups of type 3
was not deterministic; multiple runs of TTX on the same font
could therefore emit the alternates in a different order.
Since alternate glyphs are sets, this change makes no semantic
difference to the output. However, a deterministic ordering
is needed for tests that compare GSUB tables in TTX format.
