perf: memoize derived path/query projections on Uri and Url#52
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Uri and Url are immutable value objects, yet several derived projections were recomputed on every access while their siblings (canonicalUri / canonicalHref, decodedPath, decodedPathSegments) were already memoized with `by lazy`: - Uri.queryParameters() re-parsed the raw query on each call. - Uri.encodedPath re-joined every path segment on each access. - Url.pathSegments percent-decoded every segment on each access, so fileName() / fileExtension() decoded the path twice. - Url.encodedPath and Url.queryParameters recomputed likewise. Back each with a private `by lazy` field, mirroring the existing canonical/decoded caches. Public signatures are unchanged and every cached value is immutable (a String, a read-only segment list, or the QueryParameters snapshot whose entries are copied), so the change is behavior-preserving and observable only as fewer allocations on repeated reads of the same value.
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Summary
UriandUrlare immutable value objects, but a handful of their derived path/query projections were recomputed on every access, while their siblings on the same types (canonicalUri/canonicalHref,decodedPath,decodedPathSegments) were already memoized withby lazy. This backs the remaining projections with the same lazy caching.Changes
Uri.queryParameters()re-parsed the raw query (QueryParameters.parseOrEmpty) on every call — soget, thengetAll, thenhasre-parsed three times. Now reads a lazy backing snapshot.Uri.encodedPathrebuilt the path string via aStringBuilderjoin over every segment on each access. Now lazy.Url.pathSegmentspercent-decoded every segment on each access. BecausefileName()readspathSegmentsandfileExtension()callsfileName(), reading both decoded the path twice. Now lazy, so both share one decode.Url.encodedPathandUrl.queryParametersrecomputed on each access as well, and are cached here too so both value types are consistent.Each projection is now a private
by lazyfield, mirroring the existingcanonicalUri/canonicalHrefcaches. Public signatures are unchanged.Why it's safe
Every cached value is immutable: a
String, a read-only segmentList, or aQueryParameterssnapshot whose entries are copied on construction. The types are immutable value objects, so caching a derived value cannot go stale — the change is behavior-preserving and observable only as fewer allocations and less CPU on repeated reads of the same value.Verification
./gradlew :kuri:jvmTest :kuri:ktlintCheck :kuri:detekt :kuri:apiCheck— all green. No public API change, so the binary-compatibility snapshot is untouched.Closes #35