GSUnicode: stop converting at the first unrepresentable character - #123
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GSUnicode: stop converting at the first unrepresentable character#123DTW-Thalion wants to merge 2 commits into
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When encoding to ASCII or ISO Latin 1 with no loss byte, GSUnicodeToEncoding substituted a NUL byte for characters outside the target range and kept going. Stop at the first unrepresentable character instead so the caller sees how many characters were actually converted.
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When CFStringGetBytes encodes to ASCII or ISO Latin 1 and no loss byte is supplied, GSUnicodeToEncoding substituted a NUL byte (the zero loss byte) for every character outside the target range and continued, so an unconvertible string reported a full conversion made of NUL bytes.
Stop at the first unrepresentable character when no loss byte is given, leaving the source position there. The representable prefix is still converted and the returned count reflects only the characters that fit, matching Apple.
Tests/CFString/getbytes_lossless.m covers U+00E9 to ASCII, U+0100 to ISO Latin 1 and a mixed string that converts its ASCII prefix and stops. Verified against Apple CoreFoundation.