#8271: the utf-8 decoder now outputs the correct number of U+FFFD characters when used with the "replace" error handler on invalid utf-8 sequences. Patch by Serhiy Storchaka, tests by Ezio Melotti.
diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py
index 46c98bd..a811c4c 100644
--- a/Lib/test/test_unicode.py
+++ b/Lib/test/test_unicode.py
@@ -1349,7 +1349,7 @@
# with start byte of a 2-byte sequence
(b'\xc2', FFFD), # only the start byte
(b'\xc2\xc2', FFFD*2), # 2 start bytes
- (b'\xc2\xc2\xc2', FFFD*3), # 2 start bytes
+ (b'\xc2\xc2\xc2', FFFD*3), # 3 start bytes
(b'\xc2\x41', FFFD+'A'), # invalid continuation byte
# with start byte of a 3-byte sequence
(b'\xe1', FFFD), # only the start byte
@@ -1419,6 +1419,226 @@
self.assertEqual(seq.decode('utf-8', 'ignore'),
res.replace('\uFFFD', ''))
+ def to_bytestring(self, seq):
+ return bytes(int(c, 16) for c in seq.split())
+
+ def assertCorrectUTF8Decoding(self, seq, res, err):
+ """
+ Check that an invalid UTF-8 sequence raises an UnicodeDecodeError when
+ 'strict' is used, returns res when 'replace' is used, and that doesn't
+ return anything when 'ignore' is used.
+ """
+ with self.assertRaises(UnicodeDecodeError) as cm:
+ seq.decode('utf-8')
+ exc = cm.exception
+
+ self.assertIn(err, str(exc))
+ self.assertEqual(seq.decode('utf-8', 'replace'), res)
+ self.assertEqual((b'aaaa' + seq + b'bbbb').decode('utf-8', 'replace'),
+ 'aaaa' + res + 'bbbb')
+ res = res.replace('\ufffd', '')
+ self.assertEqual(seq.decode('utf-8', 'ignore'), res)
+ self.assertEqual((b'aaaa' + seq + b'bbbb').decode('utf-8', 'ignore'),
+ 'aaaa' + res + 'bbbb')
+
+ def test_invalid_start_byte(self):
+ """
+ Test that an 'invalid start byte' error is raised when the first byte
+ is not in the ASCII range or is not a valid start byte of a 2-, 3-, or
+ 4-bytes sequence. The invalid start byte is replaced with a single
+ U+FFFD when errors='replace'.
+ E.g. <80> is a continuation byte and can appear only after a start byte.
+ """
+ FFFD = '\ufffd'
+ for byte in b'\x80\xA0\x9F\xBF\xC0\xC1\xF5\xFF':
+ self.assertCorrectUTF8Decoding(bytes([byte]), '\ufffd',
+ 'invalid start byte')
+
+ def test_unexpected_end_of_data(self):
+ """
+ Test that an 'unexpected end of data' error is raised when the string
+ ends after a start byte of a 2-, 3-, or 4-bytes sequence without having
+ enough continuation bytes. The incomplete sequence is replaced with a
+ single U+FFFD when errors='replace'.
+ E.g. in the sequence <F3 80 80>, F3 is the start byte of a 4-bytes
+ sequence, but it's followed by only 2 valid continuation bytes and the
+ last continuation bytes is missing.
+ Note: the continuation bytes must be all valid, if one of them is
+ invalid another error will be raised.
+ """
+ sequences = [
+ 'C2', 'DF',
+ 'E0 A0', 'E0 BF', 'E1 80', 'E1 BF', 'EC 80', 'EC BF',
+ 'ED 80', 'ED 9F', 'EE 80', 'EE BF', 'EF 80', 'EF BF',
+ 'F0 90', 'F0 BF', 'F0 90 80', 'F0 90 BF', 'F0 BF 80', 'F0 BF BF',
+ 'F1 80', 'F1 BF', 'F1 80 80', 'F1 80 BF', 'F1 BF 80', 'F1 BF BF',
+ 'F3 80', 'F3 BF', 'F3 80 80', 'F3 80 BF', 'F3 BF 80', 'F3 BF BF',
+ 'F4 80', 'F4 8F', 'F4 80 80', 'F4 80 BF', 'F4 8F 80', 'F4 8F BF'
+ ]
+ FFFD = '\ufffd'
+ for seq in sequences:
+ self.assertCorrectUTF8Decoding(self.to_bytestring(seq), '\ufffd',
+ 'unexpected end of data')
+
+ def test_invalid_cb_for_2bytes_seq(self):
+ """
+ Test that an 'invalid continuation byte' error is raised when the
+ continuation byte of a 2-bytes sequence is invalid. The start byte
+ is replaced by a single U+FFFD and the second byte is handled
+ separately when errors='replace'.
+ E.g. in the sequence <C2 41>, C2 is the start byte of a 2-bytes
+ sequence, but 41 is not a valid continuation byte because it's the
+ ASCII letter 'A'.
+ """
+ FFFD = '\ufffd'
+ FFFDx2 = FFFD * 2
+ sequences = [
+ ('C2 00', FFFD+'\x00'), ('C2 7F', FFFD+'\x7f'),
+ ('C2 C0', FFFDx2), ('C2 FF', FFFDx2),
+ ('DF 00', FFFD+'\x00'), ('DF 7F', FFFD+'\x7f'),
+ ('DF C0', FFFDx2), ('DF FF', FFFDx2),
+ ]
+ for seq, res in sequences:
+ self.assertCorrectUTF8Decoding(self.to_bytestring(seq), res,
+ 'invalid continuation byte')
+
+ def test_invalid_cb_for_3bytes_seq(self):
+ """
+ Test that an 'invalid continuation byte' error is raised when the
+ continuation byte(s) of a 3-bytes sequence are invalid. When
+ errors='replace', if the first continuation byte is valid, the first
+ two bytes (start byte + 1st cb) are replaced by a single U+FFFD and the
+ third byte is handled separately, otherwise only the start byte is
+ replaced with a U+FFFD and the other continuation bytes are handled
+ separately.
+ E.g. in the sequence <E1 80 41>, E1 is the start byte of a 3-bytes
+ sequence, 80 is a valid continuation byte, but 41 is not a valid cb
+ because it's the ASCII letter 'A'.
+ Note: when the start byte is E0 or ED, the valid ranges for the first
+ continuation byte are limited to A0..BF and 80..9F respectively.
+ Python 2 used to consider all the bytes in range 80..BF valid when the
+ start byte was ED. This is fixed in Python 3.
+ """
+ FFFD = '\ufffd'
+ FFFDx2 = FFFD * 2
+ sequences = [
+ ('E0 00', FFFD+'\x00'), ('E0 7F', FFFD+'\x7f'), ('E0 80', FFFDx2),
+ ('E0 9F', FFFDx2), ('E0 C0', FFFDx2), ('E0 FF', FFFDx2),
+ ('E0 A0 00', FFFD+'\x00'), ('E0 A0 7F', FFFD+'\x7f'),
+ ('E0 A0 C0', FFFDx2), ('E0 A0 FF', FFFDx2),
+ ('E0 BF 00', FFFD+'\x00'), ('E0 BF 7F', FFFD+'\x7f'),
+ ('E0 BF C0', FFFDx2), ('E0 BF FF', FFFDx2), ('E1 00', FFFD+'\x00'),
+ ('E1 7F', FFFD+'\x7f'), ('E1 C0', FFFDx2), ('E1 FF', FFFDx2),
+ ('E1 80 00', FFFD+'\x00'), ('E1 80 7F', FFFD+'\x7f'),
+ ('E1 80 C0', FFFDx2), ('E1 80 FF', FFFDx2),
+ ('E1 BF 00', FFFD+'\x00'), ('E1 BF 7F', FFFD+'\x7f'),
+ ('E1 BF C0', FFFDx2), ('E1 BF FF', FFFDx2), ('EC 00', FFFD+'\x00'),
+ ('EC 7F', FFFD+'\x7f'), ('EC C0', FFFDx2), ('EC FF', FFFDx2),
+ ('EC 80 00', FFFD+'\x00'), ('EC 80 7F', FFFD+'\x7f'),
+ ('EC 80 C0', FFFDx2), ('EC 80 FF', FFFDx2),
+ ('EC BF 00', FFFD+'\x00'), ('EC BF 7F', FFFD+'\x7f'),
+ ('EC BF C0', FFFDx2), ('EC BF FF', FFFDx2), ('ED 00', FFFD+'\x00'),
+ ('ED 7F', FFFD+'\x7f'),
+ ('ED A0', FFFDx2), ('ED BF', FFFDx2), # see note ^
+ ('ED C0', FFFDx2), ('ED FF', FFFDx2), ('ED 80 00', FFFD+'\x00'),
+ ('ED 80 7F', FFFD+'\x7f'), ('ED 80 C0', FFFDx2),
+ ('ED 80 FF', FFFDx2), ('ED 9F 00', FFFD+'\x00'),
+ ('ED 9F 7F', FFFD+'\x7f'), ('ED 9F C0', FFFDx2),
+ ('ED 9F FF', FFFDx2), ('EE 00', FFFD+'\x00'),
+ ('EE 7F', FFFD+'\x7f'), ('EE C0', FFFDx2), ('EE FF', FFFDx2),
+ ('EE 80 00', FFFD+'\x00'), ('EE 80 7F', FFFD+'\x7f'),
+ ('EE 80 C0', FFFDx2), ('EE 80 FF', FFFDx2),
+ ('EE BF 00', FFFD+'\x00'), ('EE BF 7F', FFFD+'\x7f'),
+ ('EE BF C0', FFFDx2), ('EE BF FF', FFFDx2), ('EF 00', FFFD+'\x00'),
+ ('EF 7F', FFFD+'\x7f'), ('EF C0', FFFDx2), ('EF FF', FFFDx2),
+ ('EF 80 00', FFFD+'\x00'), ('EF 80 7F', FFFD+'\x7f'),
+ ('EF 80 C0', FFFDx2), ('EF 80 FF', FFFDx2),
+ ('EF BF 00', FFFD+'\x00'), ('EF BF 7F', FFFD+'\x7f'),
+ ('EF BF C0', FFFDx2), ('EF BF FF', FFFDx2),
+ ]
+ for seq, res in sequences:
+ self.assertCorrectUTF8Decoding(self.to_bytestring(seq), res,
+ 'invalid continuation byte')
+
+ def test_invalid_cb_for_4bytes_seq(self):
+ """
+ Test that an 'invalid continuation byte' error is raised when the
+ continuation byte(s) of a 4-bytes sequence are invalid. When
+ errors='replace',the start byte and all the following valid
+ continuation bytes are replaced with a single U+FFFD, and all the bytes
+ starting from the first invalid continuation bytes (included) are
+ handled separately.
+ E.g. in the sequence <E1 80 41>, E1 is the start byte of a 3-bytes
+ sequence, 80 is a valid continuation byte, but 41 is not a valid cb
+ because it's the ASCII letter 'A'.
+ Note: when the start byte is E0 or ED, the valid ranges for the first
+ continuation byte are limited to A0..BF and 80..9F respectively.
+ However, when the start byte is ED, Python 2 considers all the bytes
+ in range 80..BF valid. This is fixed in Python 3.
+ """
+ FFFD = '\ufffd'
+ FFFDx2 = FFFD * 2
+ sequences = [
+ ('F0 00', FFFD+'\x00'), ('F0 7F', FFFD+'\x7f'), ('F0 80', FFFDx2),
+ ('F0 8F', FFFDx2), ('F0 C0', FFFDx2), ('F0 FF', FFFDx2),
+ ('F0 90 00', FFFD+'\x00'), ('F0 90 7F', FFFD+'\x7f'),
+ ('F0 90 C0', FFFDx2), ('F0 90 FF', FFFDx2),
+ ('F0 BF 00', FFFD+'\x00'), ('F0 BF 7F', FFFD+'\x7f'),
+ ('F0 BF C0', FFFDx2), ('F0 BF FF', FFFDx2),
+ ('F0 90 80 00', FFFD+'\x00'), ('F0 90 80 7F', FFFD+'\x7f'),
+ ('F0 90 80 C0', FFFDx2), ('F0 90 80 FF', FFFDx2),
+ ('F0 90 BF 00', FFFD+'\x00'), ('F0 90 BF 7F', FFFD+'\x7f'),
+ ('F0 90 BF C0', FFFDx2), ('F0 90 BF FF', FFFDx2),
+ ('F0 BF 80 00', FFFD+'\x00'), ('F0 BF 80 7F', FFFD+'\x7f'),
+ ('F0 BF 80 C0', FFFDx2), ('F0 BF 80 FF', FFFDx2),
+ ('F0 BF BF 00', FFFD+'\x00'), ('F0 BF BF 7F', FFFD+'\x7f'),
+ ('F0 BF BF C0', FFFDx2), ('F0 BF BF FF', FFFDx2),
+ ('F1 00', FFFD+'\x00'), ('F1 7F', FFFD+'\x7f'), ('F1 C0', FFFDx2),
+ ('F1 FF', FFFDx2), ('F1 80 00', FFFD+'\x00'),
+ ('F1 80 7F', FFFD+'\x7f'), ('F1 80 C0', FFFDx2),
+ ('F1 80 FF', FFFDx2), ('F1 BF 00', FFFD+'\x00'),
+ ('F1 BF 7F', FFFD+'\x7f'), ('F1 BF C0', FFFDx2),
+ ('F1 BF FF', FFFDx2), ('F1 80 80 00', FFFD+'\x00'),
+ ('F1 80 80 7F', FFFD+'\x7f'), ('F1 80 80 C0', FFFDx2),
+ ('F1 80 80 FF', FFFDx2), ('F1 80 BF 00', FFFD+'\x00'),
+ ('F1 80 BF 7F', FFFD+'\x7f'), ('F1 80 BF C0', FFFDx2),
+ ('F1 80 BF FF', FFFDx2), ('F1 BF 80 00', FFFD+'\x00'),
+ ('F1 BF 80 7F', FFFD+'\x7f'), ('F1 BF 80 C0', FFFDx2),
+ ('F1 BF 80 FF', FFFDx2), ('F1 BF BF 00', FFFD+'\x00'),
+ ('F1 BF BF 7F', FFFD+'\x7f'), ('F1 BF BF C0', FFFDx2),
+ ('F1 BF BF FF', FFFDx2), ('F3 00', FFFD+'\x00'),
+ ('F3 7F', FFFD+'\x7f'), ('F3 C0', FFFDx2), ('F3 FF', FFFDx2),
+ ('F3 80 00', FFFD+'\x00'), ('F3 80 7F', FFFD+'\x7f'),
+ ('F3 80 C0', FFFDx2), ('F3 80 FF', FFFDx2),
+ ('F3 BF 00', FFFD+'\x00'), ('F3 BF 7F', FFFD+'\x7f'),
+ ('F3 BF C0', FFFDx2), ('F3 BF FF', FFFDx2),
+ ('F3 80 80 00', FFFD+'\x00'), ('F3 80 80 7F', FFFD+'\x7f'),
+ ('F3 80 80 C0', FFFDx2), ('F3 80 80 FF', FFFDx2),
+ ('F3 80 BF 00', FFFD+'\x00'), ('F3 80 BF 7F', FFFD+'\x7f'),
+ ('F3 80 BF C0', FFFDx2), ('F3 80 BF FF', FFFDx2),
+ ('F3 BF 80 00', FFFD+'\x00'), ('F3 BF 80 7F', FFFD+'\x7f'),
+ ('F3 BF 80 C0', FFFDx2), ('F3 BF 80 FF', FFFDx2),
+ ('F3 BF BF 00', FFFD+'\x00'), ('F3 BF BF 7F', FFFD+'\x7f'),
+ ('F3 BF BF C0', FFFDx2), ('F3 BF BF FF', FFFDx2),
+ ('F4 00', FFFD+'\x00'), ('F4 7F', FFFD+'\x7f'), ('F4 90', FFFDx2),
+ ('F4 BF', FFFDx2), ('F4 C0', FFFDx2), ('F4 FF', FFFDx2),
+ ('F4 80 00', FFFD+'\x00'), ('F4 80 7F', FFFD+'\x7f'),
+ ('F4 80 C0', FFFDx2), ('F4 80 FF', FFFDx2),
+ ('F4 8F 00', FFFD+'\x00'), ('F4 8F 7F', FFFD+'\x7f'),
+ ('F4 8F C0', FFFDx2), ('F4 8F FF', FFFDx2),
+ ('F4 80 80 00', FFFD+'\x00'), ('F4 80 80 7F', FFFD+'\x7f'),
+ ('F4 80 80 C0', FFFDx2), ('F4 80 80 FF', FFFDx2),
+ ('F4 80 BF 00', FFFD+'\x00'), ('F4 80 BF 7F', FFFD+'\x7f'),
+ ('F4 80 BF C0', FFFDx2), ('F4 80 BF FF', FFFDx2),
+ ('F4 8F 80 00', FFFD+'\x00'), ('F4 8F 80 7F', FFFD+'\x7f'),
+ ('F4 8F 80 C0', FFFDx2), ('F4 8F 80 FF', FFFDx2),
+ ('F4 8F BF 00', FFFD+'\x00'), ('F4 8F BF 7F', FFFD+'\x7f'),
+ ('F4 8F BF C0', FFFDx2), ('F4 8F BF FF', FFFDx2)
+ ]
+ for seq, res in sequences:
+ self.assertCorrectUTF8Decoding(self.to_bytestring(seq), res,
+ 'invalid continuation byte')
+
def test_codecs_idna(self):
# Test whether trailing dot is preserved
self.assertEqual("www.python.org.".encode("idna"), b"www.python.org.")