tooling: Adds glyphs script which assigns private-use Unicode codepoint to glyphs which are not mapped to a codepoint

misc/glyphs-scripts/assign-fallback-codepoints.py

@@ -0,0 +1,63 @@
+#
+# Assigns private-use codepoints to glyphs which are not mapped
+# to any Unicode codepoints.
+#
+# This script will ignore glyphs which name starts with "." as well as
+# empty glyphs and glyphs which are not exported.
+#
+import sys
+from collections import OrderedDict
+
+DRY_RUN = True
+
+font = Glyphs.font
+font.disableUpdateInterface()
+
+def isEmpty(g):
+  for master in g.parent.masters:
+    layer = g.layers[master.id]
+    if layer.bounds is not None and layer.bounds.size.width > 0:
+      return False
+  return True
+
+try:
+  # find next unallocated private-use codepoint
+  nextcp = 0xE000
+  for g in font.glyphs:
+    if g.unicodes is not None:
+      for c in [int(c, 16) for c in g.unicodes]:
+        if c <= 0xEFFF and c > nextcp:
+          nextcp = c + 1
+  
+  print('nextcp: %X' % nextcp)
+  if DRY_RUN:
+    print('DRY_RUN mode (no actual changes will be made)')
+  print('————————————————')
+  
+  # for printing
+  mappings = OrderedDict()
+  longest_gname = 0
+
+  # assign private-use codepoints to glyphs that have no existing unicode mapping
+  for g in font.glyphs:
+    # only care for glyphs which are being exported (also ignore "special" glyphs)
+    if g.export and g.name[0] != '.' and (g.unicodes is None or len(g.unicodes) == 0):
+      # error on empty glyphs -- there should be no unmapped empty glyphs
+      if isEmpty(g):
+        sys.stderr.write('ERR: glyph %r is empty but has no unicode mapping (skipping)\n' % g.name)
+        continue
+      unicodes = [hex(nextcp).upper()[2:]]
+      mappings[g.name] = unicodes[0]
+      if len(g.name) > longest_gname:
+        longest_gname = len(g.name)
+      if not DRY_RUN:
+        g.unicodes = unicodes
+      nextcp += 1
+
+  # print mappings made
+  for gname, cp in mappings.iteritems():
+    print('%s  %s' % (gname.ljust(longest_gname), cp))
+
+finally:
+  font.enableUpdateInterface()
+