RegexArrayShapeMatcher - (\d*) can be empty-string
#3257
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//cc @Seldaek |
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| function (string $s): void { | ||
| preg_match('/%a(\d*)?/', $s, $matches, PREG_UNMATCHED_AS_NULL); | ||
| assertType("array{0?: string, 1?: ''|numeric-string|null}", $matches); // could be array{0?: string, 1?: ''|numeric-string} |
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Good catch! What's the matter here tho?
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in this case php-src does not return NULL for the unmatched group even if PREG_UNMATCHED_AS_NULL.
that would be another special case we need to hardcode - therefore I went with leaving it less precise and have this unnecessary null in here.
I have a feeling that the ArrayShapeMatcher will get enough special cases with preg_match_all support ;)
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Yes ok, it should be ''|numeric-string, or unset if outside the true-match-arm.
PREG_UNMATCHED_AS_NULL has no impact here because (\d*) matches an empty string too, so it always matches. It's technically not optional despite the ? that follows, as long as it is not wrapped in something that contains some content.. e.g. the third example here https://3v4l.org/92geX
So I guess one rule could be that if the inside of a match group resolves to MAYBE empty string, then the match group should never be nullable as long as its parents are also not nullable.
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Thank you! |
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