src: fix two encodeInto() bugs that reject input that fits - #65998
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src: fix two encodeInto() bugs that reject input that fits#65998agape1225 wants to merge 1 commit into
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TextEncoder.encodeInto() could report that a code point does not fit in the destination Uint8Array even when it does. 1. simpleUtfEncodingLength() used 0x400 as the boundary between 2-byte and 3-byte UTF-8 encodings, but the correct boundary is 0x800: code points in [0x80, 0x800) need 2 bytes in UTF-8, and only code points >= 0x800 need 3. 2. The same function is called with a raw `char` from the Latin1 (one-byte string) code path. `char` is signed on some platforms, so a byte >= 0x80 gets sign-extended to a large uint16_t value instead of the intended code point, which also made encodeInto() behave differently for the same prefix depending on whether the rest of the source string forced V8 to represent it as one-byte (Latin1) or two-byte (UTF-16) internally. Fixes: nodejs#65994 Signed-off-by: agape1225 <49804691+agape1225@users.noreply.github.com>
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TextEncoder.encodeInto() could report that a code point does not fit in the destination Uint8Array even when it does.
simpleUtfEncodingLength() used 0x400 as the boundary between 2-byte and 3-byte UTF-8 encodings, but the correct boundary is 0x800: code points in [0x80, 0x800) need 2 bytes in UTF-8, and only code points
The same function is called with a raw
charfrom the Latin1 (one-byte string) code path.charis signed on some platforms, so a byte >= 0x80 gets sign-extended to a large uint16_t value instead of the intended code point, which also made encodeInto() behave differently for the same prefix depending on whether the rest of the source string forced V8 to represent it as one-byte (Latin1) or two-byte (UTF-16) internally.Fixes: #65994