LibRegex: Prevent empty matches in optional quantifiers #7367
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alimpfard
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Jan 7, 2026
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Looks nice, not too sure if I love a FailIfEmpty op since we have Fail + JumpNonEmpty, but I don't see a reason to not have one so it's all good.
| // CHECKPOINT _C | ||
| // REGEXP | ||
| // FAILIFEMPTY _C | ||
| // JUMP_NONEMPTY _C _START JUMP |
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Will change! Yeah, I also wasn't sure about the new op, but I've had multiple attempts at trying to do that cleanly without it and couldn't make it work nicely. Oh, and I forgot to rebaseline WPT...
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Eh, we have the opcode space, might as well use it.
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Ok, updated WPT expectations, should be good now
Step 2.b of the RepeatMatcher states that once minimum repetitions are satisfied, empty matches should not be considered for further repetitions. This was not being enforced for optional quantifiers like `?`, so we had extra capture group matches.
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Step 2.b of the RepeatMatcher states that once minimum repetitions are satisfied, empty matches should not be considered for further repetitions. This was not being enforced for quantifiers that allow 0 matches, like
?, so we had extra capture group matches.Fixes #7332
Fixes #7117
Test 262: