fix contextj joiner short-circuiting bidi check in is_label_valid - #90
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Arawoof06 wants to merge 1 commit into
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fix contextj joiner short-circuiting bidi check in is_label_valid#90Arawoof06 wants to merge 1 commit into
Arawoof06 wants to merge 1 commit into
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lemire
approved these changes
Aug 27, 2026
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is_label_valid returns a whole-label verdict as soon as it validates the first U+200C/U+200D against the ContextJ rules, so a joiner that is valid in context (say, preceded by a virama) skips the RFC 5893 Bidi checks for the rest of the label and any later joiner goes unchecked. That accepts labels it should reject: U+0915 U+094D U+200C U+0627 is an LTR label with a trailing AL, which Bidi rule 5 forbids, yet to_ascii returns xn--mgb31m2ew90g. Continue the scan on a contextually valid joiner so the Bidi rules still run and every joiner is validated.