Update PyUnicode_DecodeUTF8 from RFC 2279 to RFC 3629.
1) #8271: when a byte sequence is invalid, only the start byte and all the
valid continuation bytes are now replaced by U+FFFD, instead of replacing
the number of bytes specified by the start byte.
See http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf (pages 94-95);
2) 5- and 6-bytes-long UTF-8 sequences are now considered invalid (no changes
in behavior);
3) Add code and tests to reject surrogates (U+D800-U+DFFF) as defined in
RFC 3629, but leave it commented out since it's not backward compatible;
4) Change the error messages "unexpected code byte" to "invalid start byte"
and "invalid data" to "invalid continuation byte";
5) Add an extensive set of tests in test_unicode;
6) Fix test_codeccallbacks because it was failing after this change.
diff --git a/Lib/test/test_codeccallbacks.py b/Lib/test/test_codeccallbacks.py
index dfd12e5..635a15f 100644
--- a/Lib/test/test_codeccallbacks.py
+++ b/Lib/test/test_codeccallbacks.py
@@ -153,28 +153,30 @@
sout += "\\U%08x" % sys.maxunicode
self.assertEqual(sin.encode("iso-8859-15", "backslashreplace"), sout)
- def test_decoderelaxedutf8(self):
- # This is the test for a decoding callback handler,
- # that relaxes the UTF-8 minimal encoding restriction.
- # A null byte that is encoded as "\xc0\x80" will be
- # decoded as a null byte. All other illegal sequences
- # will be handled strictly.
+ def test_decoding_callbacks(self):
+ # This is a test for a decoding callback handler
+ # that allows the decoding of the invalid sequence
+ # "\xc0\x80" and returns "\x00" instead of raising an error.
+ # All other illegal sequences will be handled strictly.
def relaxedutf8(exc):
if not isinstance(exc, UnicodeDecodeError):
raise TypeError("don't know how to handle %r" % exc)
- if exc.object[exc.start:exc.end].startswith("\xc0\x80"):
+ if exc.object[exc.start:exc.start+2] == "\xc0\x80":
return (u"\x00", exc.start+2) # retry after two bytes
else:
raise exc
- codecs.register_error(
- "test.relaxedutf8", relaxedutf8)
+ codecs.register_error("test.relaxedutf8", relaxedutf8)
+ # all the "\xc0\x80" will be decoded to "\x00"
sin = "a\x00b\xc0\x80c\xc3\xbc\xc0\x80\xc0\x80"
sout = u"a\x00b\x00c\xfc\x00\x00"
self.assertEqual(sin.decode("utf-8", "test.relaxedutf8"), sout)
+
+ # "\xc0\x81" is not valid and a UnicodeDecodeError will be raised
sin = "\xc0\x80\xc0\x81"
- self.assertRaises(UnicodeError, sin.decode, "utf-8", "test.relaxedutf8")
+ self.assertRaises(UnicodeDecodeError, sin.decode,
+ "utf-8", "test.relaxedutf8")
def test_charmapencode(self):
# For charmap encodings the replacement string will be
diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py
index b9c062d..3171379 100644
--- a/Lib/test/test_unicode.py
+++ b/Lib/test/test_unicode.py
@@ -600,6 +600,164 @@
# * strict decoding testing for all of the
# UTF8_ERROR cases in PyUnicode_DecodeUTF8
+ def test_utf8_decode_valid_sequences(self):
+ sequences = [
+ # single byte
+ ('\x00', u'\x00'), ('a', u'a'), ('\x7f', u'\x7f'),
+ # 2 bytes
+ ('\xc2\x80', u'\x80'), ('\xdf\xbf', u'\u07ff'),
+ # 3 bytes
+ ('\xe0\xa0\x80', u'\u0800'), ('\xed\x9f\xbf', u'\ud7ff'),
+ ('\xee\x80\x80', u'\uE000'), ('\xef\xbf\xbf', u'\uffff'),
+ # 4 bytes
+ ('\xF0\x90\x80\x80', u'\U00010000'),
+ ('\xf4\x8f\xbf\xbf', u'\U0010FFFF')
+ ]
+ for seq, res in sequences:
+ self.assertEqual(seq.decode('utf-8'), res)
+
+ for ch in map(unichr, range(0, sys.maxunicode)):
+ self.assertEqual(ch, ch.encode('utf-8').decode('utf-8'))
+
+ def test_utf8_decode_invalid_sequences(self):
+ # continuation bytes in a sequence of 2, 3, or 4 bytes
+ continuation_bytes = map(chr, range(0x80, 0xC0))
+ # start bytes of a 2-byte sequence equivalent to codepoints < 0x7F
+ invalid_2B_seq_start_bytes = map(chr, range(0xC0, 0xC2))
+ # start bytes of a 4-byte sequence equivalent to codepoints > 0x10FFFF
+ invalid_4B_seq_start_bytes = map(chr, range(0xF5, 0xF8))
+ invalid_start_bytes = (
+ continuation_bytes + invalid_2B_seq_start_bytes +
+ invalid_4B_seq_start_bytes + map(chr, range(0xF7, 0x100))
+ )
+
+ for byte in invalid_start_bytes:
+ self.assertRaises(UnicodeDecodeError, byte.decode, 'utf-8')
+
+ for sb in invalid_2B_seq_start_bytes:
+ for cb in continuation_bytes:
+ self.assertRaises(UnicodeDecodeError, (sb+cb).decode, 'utf-8')
+
+ for sb in invalid_4B_seq_start_bytes:
+ for cb1 in continuation_bytes[:3]:
+ for cb3 in continuation_bytes[:3]:
+ self.assertRaises(UnicodeDecodeError,
+ (sb+cb1+'\x80'+cb3).decode, 'utf-8')
+
+ for cb in map(chr, range(0x80, 0xA0)):
+ self.assertRaises(UnicodeDecodeError,
+ ('\xE0'+cb+'\x80').decode, 'utf-8')
+ self.assertRaises(UnicodeDecodeError,
+ ('\xE0'+cb+'\xBF').decode, 'utf-8')
+ # XXX: surrogates shouldn't be valid UTF-8!
+ # see http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf
+ # (table 3-7) and http://www.rfc-editor.org/rfc/rfc3629.txt
+ #for cb in map(chr, range(0xA0, 0xC0)):
+ #sys.__stdout__.write('\\xED\\x%02x\\x80\n' % ord(cb))
+ #self.assertRaises(UnicodeDecodeError,
+ #('\xED'+cb+'\x80').decode, 'utf-8')
+ #self.assertRaises(UnicodeDecodeError,
+ #('\xED'+cb+'\xBF').decode, 'utf-8')
+ for cb in map(chr, range(0x80, 0x90)):
+ self.assertRaises(UnicodeDecodeError,
+ ('\xF0'+cb+'\x80\x80').decode, 'utf-8')
+ self.assertRaises(UnicodeDecodeError,
+ ('\xF0'+cb+'\xBF\xBF').decode, 'utf-8')
+ for cb in map(chr, range(0x90, 0xC0)):
+ self.assertRaises(UnicodeDecodeError,
+ ('\xF4'+cb+'\x80\x80').decode, 'utf-8')
+ self.assertRaises(UnicodeDecodeError,
+ ('\xF4'+cb+'\xBF\xBF').decode, 'utf-8')
+
+ def test_issue8271(self):
+ # Issue #8271: when a byte sequence is invalid, only the start byte
+ # and all the valid continuation bytes should be replaced by U+FFFD,
+ # not the number of bytes specified by the start byte.
+ # See http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf (page 95,
+ # table 3-8, Row 2) for more information about the algorithm used.
+ FFFD = u'\ufffd'
+ sequences = [
+ # invalid start bytes
+ ('\x80', FFFD), # continuation byte
+ ('\x80\x80', FFFD*2), # 2 continuation bytes
+ ('\xc0', FFFD),
+ ('\xc0\xc0', FFFD*2),
+ ('\xc1', FFFD),
+ ('\xc1\xc0', FFFD*2),
+ ('\xc0\xc1', FFFD*2),
+ # with start byte of a 2-byte sequence
+ ('\xc2', FFFD), # only the start byte
+ ('\xc2\xc2', FFFD*2), # 2 start bytes
+ ('\xc2\xc2\xc2', FFFD*3), # 2 start bytes
+ ('\xc2\x41', FFFD+'A'), # invalid continuation byte
+ # with start byte of a 3-byte sequence
+ ('\xe1', FFFD), # only the start byte
+ ('\xe1\xe1', FFFD*2), # 2 start bytes
+ ('\xe1\xe1\xe1', FFFD*3), # 3 start bytes
+ ('\xe1\xe1\xe1\xe1', FFFD*4), # 4 start bytes
+ ('\xe1\x80', FFFD), # only 1 continuation byte
+ ('\xe1\x41', FFFD+'A'), # invalid continuation byte
+ ('\xe1\x41\x80', FFFD+'A'+FFFD), # invalid cb followed by valid cb
+ ('\xe1\x41\x41', FFFD+'AA'), # 2 invalid continuation bytes
+ ('\xe1\x80\x41', FFFD+'A'), # only 1 valid continuation byte
+ ('\xe1\x80\xe1\x41', FFFD*2+'A'), # 1 valid and the other invalid
+ ('\xe1\x41\xe1\x80', FFFD+'A'+FFFD), # 1 invalid and the other valid
+ # with start byte of a 4-byte sequence
+ ('\xf1', FFFD), # only the start byte
+ ('\xf1\xf1', FFFD*2), # 2 start bytes
+ ('\xf1\xf1\xf1', FFFD*3), # 3 start bytes
+ ('\xf1\xf1\xf1\xf1', FFFD*4), # 4 start bytes
+ ('\xf1\xf1\xf1\xf1\xf1', FFFD*5), # 5 start bytes
+ ('\xf1\x80', FFFD), # only 1 continuation bytes
+ ('\xf1\x80\x80', FFFD), # only 2 continuation bytes
+ ('\xf1\x80\x41', FFFD+'A'), # 1 valid cb and 1 invalid
+ ('\xf1\x80\x41\x41', FFFD+'AA'), # 1 valid cb and 1 invalid
+ ('\xf1\x80\x80\x41', FFFD+'A'), # 2 valid cb and 1 invalid
+ ('\xf1\x41\x80', FFFD+'A'+FFFD), # 1 invalid cv and 1 valid
+ ('\xf1\x41\x80\x80', FFFD+'A'+FFFD*2), # 1 invalid cb and 2 invalid
+ ('\xf1\x41\x80\x41', FFFD+'A'+FFFD+'A'), # 2 invalid cb and 1 invalid
+ ('\xf1\x41\x41\x80', FFFD+'AA'+FFFD), # 1 valid cb and 1 invalid
+ ('\xf1\x41\xf1\x80', FFFD+'A'+FFFD),
+ ('\xf1\x41\x80\xf1', FFFD+'A'+FFFD*2),
+ ('\xf1\xf1\x80\x41', FFFD*2+'A'),
+ ('\xf1\x41\xf1\xf1', FFFD+'A'+FFFD*2),
+ # with invalid start byte of a 4-byte sequence (rfc2279)
+ ('\xf5', FFFD), # only the start byte
+ ('\xf5\xf5', FFFD*2), # 2 start bytes
+ ('\xf5\x80', FFFD*2), # only 1 continuation byte
+ ('\xf5\x80\x80', FFFD*3), # only 2 continuation byte
+ ('\xf5\x80\x80\x80', FFFD*4), # 3 continuation bytes
+ ('\xf5\x80\x41', FFFD*2+'A'), # 1 valid cb and 1 invalid
+ ('\xf5\x80\x41\xf5', FFFD*2+'A'+FFFD),
+ ('\xf5\x41\x80\x80\x41', FFFD+'A'+FFFD*2+'A'),
+ # with invalid start byte of a 5-byte sequence (rfc2279)
+ ('\xf8', FFFD), # only the start byte
+ ('\xf8\xf8', FFFD*2), # 2 start bytes
+ ('\xf8\x80', FFFD*2), # only one continuation byte
+ ('\xf8\x80\x41', FFFD*2 + 'A'), # 1 valid cb and 1 invalid
+ ('\xf8\x80\x80\x80\x80', FFFD*5), # invalid 5 bytes seq with 5 bytes
+ # with invalid start byte of a 6-byte sequence (rfc2279)
+ ('\xfc', FFFD), # only the start byte
+ ('\xfc\xfc', FFFD*2), # 2 start bytes
+ ('\xfc\x80\x80', FFFD*3), # only 2 continuation bytes
+ ('\xfc\x80\x80\x80\x80\x80', FFFD*6), # 6 continuation bytes
+ # invalid start byte
+ ('\xfe', FFFD),
+ ('\xfe\x80\x80', FFFD*3),
+ # other sequences
+ ('\xf1\x80\x41\x42\x43', u'\ufffd\x41\x42\x43'),
+ ('\xf1\x80\xff\x42\x43', u'\ufffd\ufffd\x42\x43'),
+ ('\xf1\x80\xc2\x81\x43', u'\ufffd\x81\x43'),
+ ('\x61\xF1\x80\x80\xE1\x80\xC2\x62\x80\x63\x80\xBF\x64',
+ u'\x61\uFFFD\uFFFD\uFFFD\x62\uFFFD\x63\uFFFD\uFFFD\x64'),
+ ]
+ for n, (seq, res) in enumerate(sequences):
+ self.assertRaises(UnicodeDecodeError, seq.decode, 'utf-8', 'strict')
+ self.assertEqual(seq.decode('utf-8', 'replace'), res)
+ self.assertEqual((seq+'b').decode('utf-8', 'replace'), res+'b')
+ self.assertEqual(seq.decode('utf-8', 'ignore'),
+ res.replace(u'\uFFFD', ''))
+
def test_codecs_idna(self):
# Test whether trailing dot is preserved
self.assertEqual(u"www.python.org.".encode("idna"), "www.python.org.")