Merge pull request #3525 from fonttools/cff-converters-fixes

CFF converters fixes

Lib/fontTools/cffLib/CFF2ToCFF.py

@@ -2,7 +2,13 @@
 
 from fontTools.ttLib import TTFont, newTable
 from fontTools.misc.cliTools import makeOutputFileName
-from fontTools.cffLib import TopDictIndex, buildOrder, topDictOperators
+from fontTools.cffLib import (
+    TopDictIndex,
+    buildOrder,
+    buildDefaults,
+    topDictOperators,
+    privateDictOperators,
+)
 from .width import optimizeWidths
 from collections import defaultdict
 import logging
@@ -36,16 +42,32 @@ def _convertCFF2ToCFF(cff, otFont):
     if hasattr(topDict, "VarStore"):
         raise ValueError("Variable CFF2 font cannot be converted to CFF format.")
 
-    if hasattr(topDict, "Private"):
-        privateDict = topDict.Private
-    else:
-        privateDict = None
     opOrder = buildOrder(topDictOperators)
     topDict.order = opOrder
+    for key in topDict.rawDict.keys():
+        if key not in opOrder:
+            del topDict.rawDict[key]
+            if hasattr(topDict, key):
+                delattr(topDict, key)
 
     fdArray = topDict.FDArray
     charStrings = topDict.CharStrings
 
+    defaults = buildDefaults(privateDictOperators)
+    order = buildOrder(privateDictOperators)
+    for fd in fdArray:
+        fd.setCFF2(False)
+        privateDict = fd.Private
+        privateDict.order = order
+        for key in order:
+            if key not in privateDict.rawDict and key in defaults:
+                privateDict.rawDict[key] = defaults[key]
+        for key in privateDict.rawDict.keys():
+            if key not in order:
+                del privateDict.rawDict[key]
+                if hasattr(privateDict, key):
+                    delattr(privateDict, key)
+
     for cs in charStrings.values():
         cs.decompile()
         cs.program.append("endchar")

Lib/fontTools/cffLib/CFFToCFF2.py

@@ -43,7 +43,15 @@ def _convertCFFToCFF2(cff, otFont):
     fdArray = topDict.FDArray if hasattr(topDict, "FDArray") else None
     charStrings = topDict.CharStrings
     globalSubrs = cff.GlobalSubrs
-    localSubrs = [getattr(fd.Private, "Subrs", []) for fd in fdArray] if fdArray else []
+    localSubrs = (
+        [getattr(fd.Private, "Subrs", []) for fd in fdArray]
+        if fdArray
+        else (
+            [topDict.Private.Subrs]
+            if hasattr(topDict, "Private") and hasattr(topDict.Private, "Subrs")
+            else []
+        )
+    )
 
     for glyphName in charStrings.keys():
         cs, fdIndex = charStrings.getItemAndSelector(glyphName)
@@ -70,13 +78,21 @@ def _convertCFFToCFF2(cff, otFont):
     for glyphName in charStrings.keys():
         cs, fdIndex = charStrings.getItemAndSelector(glyphName)
         program = cs.program
-        if fdIndex == None:
-            fdIndex = 0
+
+        thisLocalSubrs = (
+            localSubrs[fdIndex]
+            if fdIndex
+            else (
+                getattr(topDict.Private, "Subrs", [])
+                if hasattr(topDict, "Private")
+                else []
+            )
+        )
 
         # Intentionally use custom type for nominalWidthX, such that any
         # CharString that has an explicit width encoded will throw back to us.
         extractor = T2WidthExtractor(
-            localSubrs[fdIndex] if localSubrs else [],
+            thisLocalSubrs,
             globalSubrs,
             nominalWidthXError,
             0,
@@ -94,7 +110,7 @@ def _convertCFFToCFF2(cff, otFont):
                 op = program.pop(0)
                 bias = extractor.localBias if op == "callsubr" else extractor.globalBias
                 subrNumber += bias
-                subrSet = localSubrs[fdIndex] if op == "callsubr" else globalSubrs
+                subrSet = thisLocalSubrs if op == "callsubr" else globalSubrs
                 subrProgram = subrSet[subrNumber].program
                 program[:0] = subrProgram
             # Now pop the actual width

Lib/fontTools/cffLib/__init__.py

@@ -1470,7 +1470,7 @@ class CharsetConverter(SimpleConverter):
         else:  # offset == 0 -> no charset data.
             if isCID or "CharStrings" not in parent.rawDict:
                 # We get here only when processing fontDicts from the FDArray of
-                # CFF-CID fonts. Only the real topDict references the chrset.
+                # CFF-CID fonts. Only the real topDict references the charset.
                 assert value == 0
                 charset = None
             elif value == 0:

Lib/fontTools/cffLib/transforms.py

@@ -342,7 +342,7 @@ def _cs_drop_hints(charstring):
     del charstring._hints
 
 
-def remove_hints(cff):
+def remove_hints(cff, *, removeUnusedSubrs: bool = True):
     for fontname in cff.keys():
         font = cff[fontname]
         cs = font.CharStrings
@@ -404,6 +404,7 @@ def remove_hints(cff):
             ]:
                 if hasattr(priv, k):
                     setattr(priv, k, None)
+    if removeUnusedSubrs:
         remove_unused_subroutines(cff)
 
 

Tests/cffLib/cffLib_test.py

@@ -5,6 +5,7 @@ import copy
 import os
 import sys
 import unittest
+from io import BytesIO
 
 
 class CffLibTest(DataFilesHandler):
@@ -119,5 +120,17 @@ class CffLibTest(DataFilesHandler):
         self.assertEqual(len(glyphOrder), len(set(glyphOrder)))
 
 
+class CFFToCFF2Test(DataFilesHandler):
+
+    def test_conversion(self):
+        font_path = self.getpath("CFFToCFF2-1.otf")
+        font = TTFont(font_path)
+        from fontTools.cffLib.CFFToCFF2 import convertCFFToCFF2
+
+        convertCFFToCFF2(font)
+        f = BytesIO()
+        font.save(f)
+
+
 if __name__ == "__main__":
     sys.exit(unittest.main())