From 5777c2e057ee906642d45f9ecb734da293c4b61d Mon Sep 17 00:00:00 2001 From: Cosimo Lupo Date: Fri, 17 Apr 2020 17:22:45 +0100 Subject: [PATCH] feaLib.builder: skip getAlternateGlyphs if lookup is None in ChainContextSubstBuilder Fixes https://github.com/googlefonts/fontmake/issues/648 --- Lib/fontTools/feaLib/builder.py | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/Lib/fontTools/feaLib/builder.py b/Lib/fontTools/feaLib/builder.py index 6e654374a..51d57c792 100644 --- a/Lib/fontTools/feaLib/builder.py +++ b/Lib/fontTools/feaLib/builder.py @@ -1311,9 +1311,10 @@ class ChainContextSubstBuilder(LookupBuilder): if lookups == self.SUBTABLE_BREAK_: continue for lookup in lookups: - alts = lookup.getAlternateGlyphs() - for glyph, replacements in alts.items(): - result.setdefault(glyph, set()).update(replacements) + if lookup is not None: + alts = lookup.getAlternateGlyphs() + for glyph, replacements in alts.items(): + result.setdefault(glyph, set()).update(replacements) return result def find_chainable_single_subst(self, glyphs):