Fix an oversight in the UTF-32 endian sniffing. (#18)

(I'd commented about the heuristic of characters at the start of the plane
being rare, but failed to actually implement said heuristic, only having
implemented the detection of the high eight bits (which can be expanded
to eleven) having to be false.)
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HarJIT 2021-10-13 09:04:11 +01:00 committed by GitHub
parent caf3c1a227
commit 14db828233
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@ -871,9 +871,14 @@ class Utf32IncrementalDecoder(IncrementalDecoder):
else if i == 0xFFFE0000:
self.state = 1
i = None
else if i & 0xFF000000:
# UTF-32's highest byte will never be used, so if it has a value it's obviously
# the other endian.
else if i & 0xFFE00000:
# UTF-32's highest eleven bits will never be used, so if they have a value it's
# obviously the other endian.
self.state = 1
i = data[offset + 3] | (data[offset + 2] << 8) | (data[offset + 1] << 16) | (data[offset] << 24)
else if not i & 0xFFFF:
# More likely to the the other endian than the first character in a plane (null,
# a Linear B character, two rare Chinese characters and two PUA characters).
self.state = 1
i = data[offset + 3] | (data[offset + 2] << 8) | (data[offset + 1] << 16) | (data[offset] << 24)
else: