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fix: lazy quantifiers matched greedily (#175) - #181
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The char class searcher and the composite searcher scan greedily, so `\d+?` on "11" returned [0 2] instead of [0 1]. Patterns with a lazy quantifier now use another strategy there. Co-authored-by: Andrey Kolkov <3740898+kolkov@users.noreply.github.com>
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Covers the cases in #175 that go through the char class and composite searchers, building on the ones @kolkov posted there (the first five rows of the new test).
The char class searcher and the composite searcher scan greedily, so they ignored lazy quantifiers.
\d+?on"11"returned[0 2]where the stdlib returns[0 1] [1 2], and\w+?\s??\w?on"1A\nc"returned[0 4]where the stdlib returns[0 2] [3 4]. Patterns with a lazy quantifier now skip those two searchers. That's slower on those paths:\d+?over 100 KB goes from about 75 to 371 microseconds.Two related cases aren't fixed here. The submatch of
(\d+?)on"11"is still[0 2 0 2]because the OnePass DFA never stops at a lazy match..*?aon"xaax"still returns[0 3]because the reverse suffix search takes.*?for.*.Added
TestIssue175_LazyQuantifier, run withgo test ./....Assisted by Claude/Codex.
Co-authored-by: Andrey Kolkov 3740898+kolkov@users.noreply.github.com