fix: Scala 3.9 compatibility fixes#1074
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Motivation: sbt lint reported 45 unused keys across sub-projects. Modification: Add projectInfoVersion, mimaReportSignatureProblems, autoAPIMappings, and unidocProjectFilter to excludeLintKeys in project/Common.scala globalSettings. Result: sbt lint warnings resolved. Tests: - sbt "http-core / compile; http / compile; parsing / compile" - sbt lint warnings resolved - sbt "http-caching / compile; http-cors / compile; http-testkit / compile" - sbt lint warnings resolved References: None - build configuration cleanup
Motivation: Scala 3.9.0-RC1 introduces several breaking changes: 1. -language:_ wildcard option is no longer accepted 2. -Yfuture-lazy-vals option removed (now default behavior) 3. -Ywarn-dead-code is Scala 2 only 4. Context bound desugaring changes, breaking explicit ClassTag/Tuple/ LogSource passing patterns Modification: - build.sbt: make -language:_ conditional on Scala 3 < 3.9 - project/Common.scala: move -Ywarn-dead-code to Scala 2 only, conditionally include -Yfuture-lazy-vals for Scala 3 < 3.9 - HttpMessage.scala, RejectionHandler.scala, PredefinedToResponseMarshallers.scala: use implicit val ClassTag instead of context bound [T: ClassTag] - Directive.scala, BasicDirectives.scala, PathMatcher.scala: use implicit val Tuple instead of context bound [L: Tuple] - PoolInterface.scala, StageLoggingWithOverride.scala: use implicit val LogSource instead of explicit passing Result: pekko-http parsing, http-core, http, and http-testkit modules compile cleanly with Scala 3.9.0-RC1. Tests: - sbt "++3.9.0-RC1!; parsing/compile; http-core/compile; http/compile; http-testkit/compile" passes References: None - Scala 3.9 forward compatibility
pjfanning
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Jun 19, 2026
Motivation: The same scalacOptions block for `-language:_` (excluded on Scala 3.9+) was repeated inline in 3 places in build.sbt. Modification: Add `Common.notOnScala39Plus` helper and replace all 3 inline blocks. Result: Single source of truth for the Scala 3.9+ language option exclusion. Tests: Not run - build config only References: Refs apache#1074
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Jun 19, 2026
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Done. Extracted notOnScala39Plus helper in Common.scala and replaced all 3 inline blocks.
Motivation: The previous commit used unqualified `notOnScala39Plus` which is not in scope in build.sbt, causing compilation failure. Modification: Prefix all 3 call sites with `Common.` and run scalafmt. Result: build.sbt compiles successfully with the shared helper. Tests: Not run - build config fix References: Refs apache#1074
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Motivation
Scala 3.9.0-RC1 introduces several breaking changes:
-language:_wildcard option is no longer accepted-Yfuture-lazy-valsoption removed (behavior is now default)-Ywarn-dead-codeis Scala 2 onlyClassTag/Tuple/LogSourcepassing patternsModification
-language:_conditional on Scala 3 minor < 9-Ywarn-dead-codeto Scala 2 only, conditionally include-Yfuture-lazy-valsfor Scala 3 < 3.9implicit val ClassTaginstead of context bound[T: ClassTag]implicit val Tupleinstead of context bound[L: Tuple]implicit val LogSourceinstead of explicit passingResult
pekko-http
parsing,http-core,http, andhttp-testkitmodules compile cleanly with Scala 3.9.0-RC1.Tests
sbt "++3.9.0-RC1!; parsing/compile; http-core/compile; http/compile; http-testkit/compile"passesReferences
None - Scala 3.9 forward compatibility