quoted-printable fix_leading_dot() no longer cuts the line in the mid…

…dle of a quoted character

flanker/mime/message/part.py

@@ -730,8 +730,8 @@ def _quote_and_cut(ln):
 
         # Should be a quoted character
         if c == b'=':
-            # Peak ahead, do the next 2 chars appear to be a hex values?
-            if quopri.ishex(ln[pos+1:pos+3]):
+            # Peak ahead, does the next char appear to be a hex value?
+            if quopri.ishex(ln[pos+1:pos+2]):
                 in_quote = 1
             continue
 

tests/mime/message/headers/part_test.py

@@ -136,6 +136,13 @@
      '=2Equick brown fox, quick brown cat    =09=\n' +
      '                 quick read dog, quic=\n' +
      'k white bird'),
+    # Should avoid cutting in the middle of multiple quoted characters near the cut point
+    (b'zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz' +
+     b'.foo. 🙂 also there is 🙂 more in 🙂 this 🙂 message</body></html>',
+     'zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz=\n' +
+     '=2Efoo. =F0=9F=99=82 also there is =F0=9F=\n' +
+     '=99=82 more in =F0=9F=99=82 this =F0=\n'
+     '=9F=99=82 message</body></html>'),
 )