diff options
Diffstat (limited to 'Lib/fontTools/varLib/featureVars.py')
| -rw-r--r-- | Lib/fontTools/varLib/featureVars.py | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/Lib/fontTools/varLib/featureVars.py b/Lib/fontTools/varLib/featureVars.py index 76e8cc4a..45f3d839 100644 --- a/Lib/fontTools/varLib/featureVars.py +++ b/Lib/fontTools/varLib/featureVars.py @@ -10,7 +10,7 @@ from fontTools.ttLib.tables import otTables as ot from fontTools.otlLib.builder import buildLookup, buildSingleSubstSubtable from collections import OrderedDict -from .errors import VarLibValidationError +from .errors import VarLibError, VarLibValidationError def addFeatureVariations(font, conditionalSubstitutions, featureTag='rvrn'): @@ -298,6 +298,11 @@ def addFeatureVariationsRaw(font, conditionalSubstitutions, featureTag='rvrn'): varFeatureIndex = gsub.FeatureList.FeatureRecord.index(varFeature) for scriptRecord in gsub.ScriptList.ScriptRecord: + if scriptRecord.Script.DefaultLangSys is None: + raise VarLibError( + "Feature variations require that the script " + f"'{scriptRecord.ScriptTag}' defines a default language system." + ) langSystems = [lsr.LangSys for lsr in scriptRecord.Script.LangSysRecord] for langSys in [scriptRecord.Script.DefaultLangSys] + langSystems: langSys.FeatureIndex.append(varFeatureIndex) |