fix(match): AnyOf.Len keeps variable length when first alt is variable - #72
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fix(match): AnyOf.Len keeps variable length when first alt is variable#72Solaris-star wants to merge 1 commit into
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AnyOf.Len used l == -1 both as "unset" and as the variable-length
sentinel. A first alternative with Len() == -1 (e.g. Suffix from "**/x")
was therefore overwritten by a later fixed-length alternative, so
patterns like "{**/daxing,daxing}/..." reported a fixed length, got
glued into a Row, and failed to match.
Fixes gobwas#66
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Summary
Brace patterns with exactly two alternatives failed when the first alternative had variable length (e.g.
**/…→Suffix) and the second had fixed length.Root cause
AnyOf.Len()initializedl = -1and treatedl == -1as “not set yet”.-1is also the variable-length sentinel from matchers likeSuffix/Super.So a leading variable-length alt was overwritten by a later fixed-length alt,
Len()returned a fixed size, andglueMatchersAsRowbuilt aRowthat cannot match longer prefixes.Fix
Initialize length from the first matcher explicitly and return
-1as soon as any alternative is variable-length or lengths disagree.Test plan
go test ./match ./compiler .TestAnyOfLen(leading variable-length regression)TestBraceTwoAlternativesWithSuper(issue repro)Fixes #66