subset: remove FeatureVariations table and downgrade to version 0x100…

…00 when empty fonttools#1881 (comment)
anthrotype · Apr 28, 2020 · c8f591e · c8f591e
1 parent 3f7b042
commit c8f591e
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Showing 2 changed files with 6 additions and 5 deletions.
diff --git a/Lib/fontTools/subset/__init__.py b/Lib/fontTools/subset/__init__.py
@@ -1631,11 +1631,11 @@ def prune_post_subset(self, font, options):
 	#if table.ScriptList and not table.ScriptList.ScriptRecord:
 	#	table.ScriptList = None
 
-	if not table.FeatureList and hasattr(table, 'FeatureVariations'):
-		table.FeatureVariations = None
+	if hasattr(table, 'FeatureVariations'):
+		if not (table.FeatureList and table.FeatureVariations.FeatureVariationRecord):
+			table.FeatureVariations = None
 
-	if hasattr(table, 'FeatureVariations') and not table.FeatureVariations:
-		if table.Version == 0x00010001:
+		if not table.FeatureVariations and table.Version == 0x00010001:
 			table.Version = 0x00010000
 
 	return True

diff --git a/Tests/subset/subset_test.py b/Tests/subset/subset_test.py
@@ -793,7 +793,8 @@ def test_subset_feature_variations_drop_all(featureVarsTestFont):
     assert "rvrn" not in featureTags
     assert glyphs == {".notdef", "f", "dollar"}
     # all FeatureVariationRecords were dropped
-    assert not font["GSUB"].table.FeatureVariations.FeatureVariationRecord
+    assert font["GSUB"].table.FeatureVariations is None
+    assert font["GSUB"].table.Version == 0x00010000
 
 
 # TODO test_subset_feature_variations_drop_from_end_empty_records