com.google.fonts/check/mac_style: Skip if font.style is None

If font.style is None, the test currently errors/

Related to #4349, but not
a complete fix.

CHANGELOG.md

@@ -11,6 +11,7 @@ A more detailed list of changes is available in the corresponding milestones for
 ### Changes to existing checks
 #### On the Open Type Profile
   - **[com.google.fonts/check/layout_valid_feature_tags]:** Updated the check to allow valid private-use feature tags. (issue #4544)
+  - **[com.google.fonts/check/mac_style]:** Skip if font style can not be determined. (issue #4349)
 
 
 ## 0.12.0a2 (2024-Feb-21)

Lib/fontbakery/checks/opentype/head.py

@@ -1,7 +1,7 @@
 import fractions
 
 from fontbakery.callable import check
-from fontbakery.status import FAIL, PASS, WARN
+from fontbakery.status import FAIL, PASS, WARN, SKIP
 from fontbakery.message import Message
 from fontbakery.constants import NameID
 
@@ -191,6 +191,10 @@ def com_google_fonts_check_mac_style(font):
     from fontbakery.utils import check_bit_entry
     from fontbakery.constants import MacStyle
 
+    if font.style is None:
+        yield SKIP, "Font style could not be determined."
+        return
+
     # Checking macStyle ITALIC bit:
     expected = "Italic" in font.style
     yield check_bit_entry(

tests/checks/opentype/head_test.py

@@ -1,9 +1,10 @@
 from fontTools.ttLib import TTFont
 import pytest
 
-from fontbakery.status import WARN, FAIL, PASS
+from fontbakery.status import WARN, FAIL, PASS, SKIP
 from fontbakery.codetesting import (
     assert_PASS,
+    assert_SKIP,
     assert_results_contain,
     CheckTester,
     TEST_FILE,
@@ -194,6 +195,7 @@ def test_check_mac_style():
         [MacStyle.BOLD, "Bold", PASS],
         [MacStyle.BOLD, "Thin", "bad-BOLD"],
         [MacStyle.BOLD | MacStyle.ITALIC, "BoldItalic", PASS],
+        [0, None, SKIP],
     ]
 
     for macStyle_value, style, expected in test_cases:
@@ -204,6 +206,11 @@ def test_check_mac_style():
                 check(MockFont(ttFont=ttFont, style=style)),
                 "with macStyle:{macStyle_value} style:{style}...",
             )
+        elif expected == SKIP:
+            assert_SKIP(
+                check(MockFont(ttFont=ttFont, style=style)),
+                "with macStyle:{macStyle_value} style:{style}...",
+            )
         else:
             assert_results_contain(
                 check(MockFont(ttFont=ttFont, style=style)),