1 files changed, 28 insertions, 0 deletions
diff --git a/Lib/fontTools/misc/testTools.py b/Lib/fontTools/misc/testTools.py
index db316a82..871a9951 100644
--- a/Lib/fontTools/misc/testTools.py
+++ b/Lib/fontTools/misc/testTools.py
@@ -3,10 +3,12 @@
 from collections.abc import Iterable
 from io import BytesIO
 import os
+import re
 import shutil
 import sys
 import tempfile
 from unittest import TestCase as _TestCase
+from fontTools.config import Config
 from fontTools.misc.textTools import tobytes
 from fontTools.misc.xmlWriter import XMLWriter
 
@@ -52,6 +54,7 @@ class FakeFont:
         self.reverseGlyphOrderDict_ = {g: i for i, g in enumerate(glyphs)}
         self.lazy = False
         self.tables = {}
+        self.cfg = Config()
 
     def __getitem__(self, tag):
         return self.tables[tag]
@@ -133,6 +136,31 @@ def getXML(func, ttFont=None):
     return xml.splitlines()
 
 
+def stripVariableItemsFromTTX(
+    string: str,
+    ttLibVersion: bool = True,
+    checkSumAdjustment: bool = True,
+    modified: bool = True,
+    created: bool = True,
+    sfntVersion: bool = False,  # opt-in only
+) -> str:
+    """Strip stuff like ttLibVersion, checksums, timestamps, etc. from TTX dumps."""
+    # ttlib changes with the fontTools version
+    if ttLibVersion:
+        string = re.sub(' ttLibVersion="[^"]+"', "", string)
+    # sometimes (e.g. some subsetter tests) we don't care whether it's OTF or TTF
+    if sfntVersion:
+        string = re.sub(' sfntVersion="[^"]+"', "", string)
+    # head table checksum and creation and mod date changes with each save.
+    if checkSumAdjustment:
+        string = re.sub('<checkSumAdjustment value="[^"]+"/>', "", string)
+    if modified:
+        string = re.sub('<modified value="[^"]+"/>', "", string)
+    if created:
+        string = re.sub('<created value="[^"]+"/>', "", string)
+    return string
+
+
 class MockFont(object):
     """A font-like object that automatically adds any looked up glyphname
     to its glyphOrder."""