Check for existing swap by oldName instead of checking for the pair

googlefonts · Sep 26, 2023 · fdc9643 · fdc9643
1 parent 10af377
commit fdc9643
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/Lib/fontmake/instantiator.py b/Lib/fontmake/instantiator.py
@@ -168,7 +168,8 @@ def process_rules_swaps(rules, location, glyphNames):
                 # I guess it should be, so that we can swap, and if it isn't,
                 # then it's better to error out later when we try to swap,
                 # instead of silently ignoring the rule here.
-                if oldName in glyphNames and (oldName, newName) not in swaps:
+                # Also checking for duplication of rules by oldName here:
+                if oldName in glyphNames and oldName not in [swap[0] for swap in swaps]:
                     swaps.append((oldName, newName))
     return swaps