Regression in `scalalandio/chimney` - missing span

[WojciechMazur]

Based on OpenCB failure in scalalandio/chimney - OpenCB logs

Compiler version

Last good revision: 3.7.1-RC1-bin-20250411-f4847cc-NIGHTLY
First bad revision: 3.7.1-RC1-bin-20250412-e70ea84-NIGHTLY

Bisect points to either:
d72e5ea
19dcfa2
However these 2 fail with different errors. The exact commit that introduced regression is not yet known

Not yet minimized

Needs minimisation, unfortunately I won't be able to provide one before 28th April

Output (click arrow to expand)

Error:  java.lang.AssertionError: assertion failed
Error:  scala.runtime.Scala3RunTime$.assertFailed(Scala3RunTime.scala:11)
Error:  dotty.tools.dotc.util.Spans$Span$.start$extension(Spans.scala:45)
Error:  dotty.tools.dotc.typer.Migrations.implicitParams(Migrations.scala:137)
Error:  dotty.tools.dotc.typer.Migrations.implicitParams$(Migrations.scala:28)
Error:  dotty.tools.dotc.typer.Typer.implicitParams(Typer.scala:154)
Error:  dotty.tools.dotc.typer.Typer.adaptToArgs$1(Typer.scala:4204)
....

[info] 
[info]   exception occurred while typechecking /build/repo/chimney/src/main/scala/io/scalaland/chimney/internal/compiletime/derivation/patcher/rules/PatchCollectionWithOptionCollectionRuleModule.scala
[info] 
[info]   An unhandled exception was thrown in the compiler.
[info]   Please file a crash report here:
[info]   https://github.com/scala/scala3/issues/new/choose
[info]   For non-enriched exceptions, compile with -Xno-enrich-error-messages.
[info] 
[info] 
[info]      while compiling: /build/repo/chimney/src/main/scala/io/scalaland/chimney/internal/compiletime/derivation/patcher/rules/PatchCollectionWithOptionCollectionRuleModule.scala
[info]         during phase: typer
[info]                 mode: Mode(ImplicitsEnabled)
[info]      library version: version 2.13.16
[info]     compiler version: version 3.7.1-RC1-bin-20250417-05b102a-NIGHTLY-git-05b102a
[info]             settings: -Wconf List(msg=Unreachable case:s, msg=Missing symbol position:s, msg=can be rewritten automatically under:s) -Wnonunit-statement true -Wunused List(privates, locals, explicits, implicits, params) -Wvalue-discard true -Xcheck-macros true -Xkind-projector underscores -classpath /build/repo/chimney/target/jvm-3/classes:/build/repo/chimney-macro-commons/target/jvm-3/classes:/root/.cache/coursier/v1/https/repo1.maven.org/maven2/org/scala-lang/scala3-library_3/3.7.1-RC1-bin-20250417-05b102a-NIGHTLY/scala3-library_3-3.7.1-RC1-bin-20250417-05b102a-NIGHTLY.jar:/root/.cache/coursier/v1/https/repo1.maven.org/maven2/org/scala-lang/modules/scala-collection-compat_3/2.13.0/scala-collection-compat_3-2.13.0.jar:/root/.cache/coursier/v1/https/repo1.maven.org/maven2/org/scala-lang/scala-library/2.13.16/scala-library-2.13.16.jar -d /build/repo/chimney/target/jvm-3/classes -explain true -explain-types true -no-indent true -rewrite Some(dotty.tools.dotc.rewrites.Rewrites@18e19f68) -source 3.3-migration
Error:  ## Exception when compiling 140 sources to /build/repo/chimney/target/jvm-3/classes
Error:  java.lang.AssertionError: assertion failed
Error:  scala.runtime.Scala3RunTime$.assertFailed(Scala3RunTime.scala:11)
Error:  dotty.tools.dotc.util.Spans$Span$.start$extension(Spans.scala:45)
Error:  dotty.tools.dotc.typer.Migrations.implicitParams(Migrations.scala:137)
Error:  dotty.tools.dotc.typer.Migrations.implicitParams$(Migrations.scala:28)
Error:  dotty.tools.dotc.typer.Typer.implicitParams(Typer.scala:154)
Error:  dotty.tools.dotc.typer.Typer.adaptToArgs$1(Typer.scala:4204)
Error:  dotty.tools.dotc.typer.Typer.adapt1(Typer.scala:4872)
Error:  dotty.tools.dotc.typer.Typer.adapt(Typer.scala:4107)
Error:  dotty.tools.dotc.typer.Typer.readapt$1(Typer.scala:4117)
Error:  dotty.tools.dotc.typer.Typer.adapt1(Typer.scala:4865)
Error:  dotty.tools.dotc.typer.Typer.adapt(Typer.scala:4107)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3843)
Error:  dotty.tools.dotc.typer.Applications.tryWithProto$1(Applications.scala:1534)
Error:  dotty.tools.dotc.typer.Applications.tryWithTypeArgs$1$$anonfun$1(Applications.scala:1546)
Error:  dotty.tools.dotc.typer.Typer$.tryEither(Typer.scala:127)
Error:  dotty.tools.dotc.typer.Applications.tryWithTypeArgs$1(Applications.scala:1554)
Error:  dotty.tools.dotc.typer.Applications.tryWithName$1(Applications.scala:1561)
Error:  dotty.tools.dotc.typer.Applications.trySelectUnapply$1(Applications.scala:1575)
Error:  dotty.tools.dotc.typer.Applications.typedUnApply(Applications.scala:1583)
Error:  dotty.tools.dotc.typer.Applications.typedUnApply$(Applications.scala:465)
Error:  dotty.tools.dotc.typer.Typer.typedUnApply(Typer.scala:154)
Error:  dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3562)
Error:  dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3650)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Applications$UnapplyArgs.typedPatterns$$anonfun$2(Applications.scala:289)
Error:  scala.collection.LazyZip2$$anon$1$$anon$2.next(LazyZipOps.scala:42)
Error:  scala.collection.immutable.List.prependedAll(List.scala:153)
Error:  scala.collection.immutable.List$.from(List.scala:685)
Error:  scala.collection.immutable.List$.from(List.scala:682)
Error:  scala.collection.BuildFromLowPriority2$$anon$11.fromSpecific(BuildFrom.scala:115)
Error:  scala.collection.BuildFromLowPriority2$$anon$11.fromSpecific(BuildFrom.scala:112)
Error:  scala.collection.LazyZip2.map(LazyZipOps.scala:37)
Error:  dotty.tools.dotc.typer.Applications$UnapplyArgs.typedPatterns(Applications.scala:289)
Error:  dotty.tools.dotc.typer.Applications.typedUnApply(Applications.scala:1680)
Error:  dotty.tools.dotc.typer.Applications.typedUnApply$(Applications.scala:465)
Error:  dotty.tools.dotc.typer.Typer.typedUnApply(Typer.scala:154)
Error:  dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3562)
Error:  dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3650)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Typer.typedTuple(Typer.scala:3461)
Error:  dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3600)
Error:  dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3650)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Typer.typedPattern(Typer.scala:3864)
Error:  dotty.tools.dotc.typer.Typer.typedCase(Typer.scala:2286)
Error:  dotty.tools.dotc.typer.Typer.typedCases$$anonfun$1(Typer.scala:2212)
Error:  dotty.tools.dotc.core.Decorators$.loop$1(Decorators.scala:99)
Error:  dotty.tools.dotc.core.Decorators$.mapconserve(Decorators.scala:115)
Error:  dotty.tools.dotc.typer.Typer.typedCases(Typer.scala:2211)
Error:  dotty.tools.dotc.typer.Typer.$anonfun$39(Typer.scala:2194)
Error:  dotty.tools.dotc.typer.Applications.harmonic(Applications.scala:2663)
Error:  dotty.tools.dotc.typer.Applications.harmonic$(Applications.scala:465)
Error:  dotty.tools.dotc.typer.Typer.harmonic(Typer.scala:154)
Error:  dotty.tools.dotc.typer.Typer.typedMatchFinish(Typer.scala:2194)
Error:  dotty.tools.dotc.typer.Typer.typedMatch(Typer.scala:2122)
Error:  dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3577)
Error:  dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3650)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3843)
Error:  dotty.tools.dotc.typer.Typer.$anonfun$66(Typer.scala:2954)
Error:  dotty.tools.dotc.inlines.PrepareInlineable$.dropInlineIfError(PrepareInlineable.scala:256)
Error:  dotty.tools.dotc.typer.Typer.typedDefDef(Typer.scala:2954)
Error:  dotty.tools.dotc.typer.Typer.typedNamed$1(Typer.scala:3544)
Error:  dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3649)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Typer.traverse$1(Typer.scala:3754)
Error:  dotty.tools.dotc.typer.Typer.typedStats(Typer.scala:3800)
Error:  dotty.tools.dotc.typer.Typer.typedClassDef(Typer.scala:3222)
Error:  dotty.tools.dotc.typer.Typer.typedTypeOrClassDef$1(Typer.scala:3550)
Error:  dotty.tools.dotc.typer.Typer.typedNamed$1(Typer.scala:3554)
Error:  dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3649)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Typer.traverse$1(Typer.scala:3754)
Error:  dotty.tools.dotc.typer.Typer.typedStats(Typer.scala:3800)
Error:  dotty.tools.dotc.typer.Typer.typedClassDef(Typer.scala:3222)
Error:  dotty.tools.dotc.typer.Typer.typedTypeOrClassDef$1(Typer.scala:3550)
Error:  dotty.tools.dotc.typer.Typer.typedNamed$1(Typer.scala:3554)
Error:  dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3649)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Typer.traverse$1(Typer.scala:3754)
Error:  dotty.tools.dotc.typer.Typer.typedStats(Typer.scala:3800)
Error:  dotty.tools.dotc.typer.Typer.typedPackageDef(Typer.scala:3355)
Error:  dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3596)
Error:  dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3650)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3727)
Error:  dotty.tools.dotc.typer.Typer.typed(Typer.scala:3732)
Error:  dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3843)
Error:  dotty.tools.dotc.typer.TyperPhase.typeCheck$$anonfun$1(TyperPhase.scala:47)
Error:  scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
Error:  scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
Error:  dotty.tools.dotc.core.Phases$Phase.monitor(Phases.scala:510)
Error:  dotty.tools.dotc.typer.TyperPhase.typeCheck(TyperPhase.scala:53)
Error:  dotty.tools.dotc.typer.TyperPhase.$anonfun$4(TyperPhase.scala:99)
Error:  scala.collection.Iterator$$anon$6.hasNext(Iterator.scala:479)
Error:  scala.collection.Iterator$$anon$9.hasNext(Iterator.scala:583)
Error:  scala.collection.immutable.List.prependedAll(List.scala:155)
Error:  scala.collection.immutable.List$.from(List.scala:685)
Error:  scala.collection.immutable.List$.from(List.scala:682)
Error:  scala.collection.IterableOps$WithFilter.map(Iterable.scala:900)
Error:  dotty.tools.dotc.typer.TyperPhase.runOn(TyperPhase.scala:98)
Error:  dotty.tools.dotc.Run.runPhases$1$$anonfun$1(Run.scala:368)
Error:  scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
Error:  scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
Error:  scala.collection.ArrayOps$.foreach$extension(ArrayOps.scala:1324)
Error:  dotty.tools.dotc.Run.runPhases$1(Run.scala:361)
Error:  dotty.tools.dotc.Run.compileUnits$$anonfun$1$$anonfun$2(Run.scala:408)
Error:  dotty.tools.dotc.Run.compileUnits$$anonfun$1$$anonfun$adapted$1(Run.scala:408)
Error:  scala.Function0.apply$mcV$sp(Function0.scala:42)
Error:  dotty.tools.dotc.Run.showProgress(Run.scala:470)
Error:  dotty.tools.dotc.Run.compileUnits$$anonfun$1(Run.scala:408)
Error:  dotty.tools.dotc.Run.compileUnits$$anonfun$adapted$1(Run.scala:420)
Error:  dotty.tools.dotc.util.Stats$.maybeMonitored(Stats.scala:69)
Error:  dotty.tools.dotc.Run.compileUnits(Run.scala:420)
Error:  dotty.tools.dotc.Run.compileSources(Run.scala:307)
Error:  dotty.tools.dotc.Run.compile(Run.scala:292)
Error:  dotty.tools.dotc.Driver.doCompile(Driver.scala:37)
Error:  dotty.tools.xsbt.CompilerBridgeDriver.run(CompilerBridgeDriver.java:141)
Error:  dotty.tools.xsbt.CompilerBridge.run(CompilerBridge.java:22)
Error:  sbt.internal.inc.AnalyzingCompiler.compile(AnalyzingCompiler.scala:91)
Error:  sbt.internal.inc.MixedAnalyzingCompiler.$anonfun$compile$7(MixedAnalyzingCompiler.scala:196)
Error:  scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:23)
Error:  sbt.internal.inc.MixedAnalyzingCompiler.timed(MixedAnalyzingCompiler.scala:252)
Error:  sbt.internal.inc.MixedAnalyzingCompiler.$anonfun$compile$4(MixedAnalyzingCompiler.scala:186)
Error:  sbt.internal.inc.MixedAnalyzingCompiler.$anonfun$compile$4$adapted(MixedAnalyzingCompiler.scala:166)
Error:  sbt.internal.inc.JarUtils$.withPreviousJar(JarUtils.scala:241)
Error:  sbt.internal.inc.MixedAnalyzingCompiler.compileScala$1(MixedAnalyzingCompiler.scala:166)
Error:  sbt.internal.inc.MixedAnalyzingCompiler.compile(MixedAnalyzingCompiler.scala:214)
Error:  sbt.internal.inc.IncrementalCompilerImpl.$anonfun$compileInternal$1(IncrementalCompilerImpl.scala:542)
Error:  sbt.internal.inc.IncrementalCompilerImpl.$anonfun$compileInternal$1$adapted(IncrementalCompilerImpl.scala:542)
Error:  sbt.internal.inc.Incremental$.$anonfun$apply$3(Incremental.scala:182)
Error:  sbt.internal.inc.Incremental$.$anonfun$apply$3$adapted(Incremental.scala:180)
Error:  sbt.internal.inc.Incremental$$anon$2.run(Incremental.scala:458)
Error:  sbt.internal.inc.IncrementalCommon$CycleState.next(IncrementalCommon.scala:117)
Error:  sbt.internal.inc.IncrementalCommon$$anon$1.next(IncrementalCommon.scala:56)
Error:  sbt.internal.inc.IncrementalCommon$$anon$1.next(IncrementalCommon.scala:52)
Error:  sbt.internal.inc.IncrementalCommon.cycle(IncrementalCommon.scala:263)
Error:  sbt.internal.inc.Incremental$.$anonfun$incrementalCompile$8(Incremental.scala:413)
Error:  sbt.internal.inc.Incremental$.withClassfileManager(Incremental.scala:500)
Error:  sbt.internal.inc.Incremental$.incrementalCompile(Incremental.scala:400)
Error:  sbt.internal.inc.Incremental$.apply(Incremental.scala:208)
Error:  sbt.internal.inc.IncrementalCompilerImpl.compileInternal(IncrementalCompilerImpl.scala:542)
Error:  sbt.internal.inc.IncrementalCompilerImpl.$anonfun$compileIncrementally$1(IncrementalCompilerImpl.scala:496)
Error:  sbt.internal.inc.IncrementalCompilerImpl.handleCompilationError(IncrementalCompilerImpl.scala:332)
Error:  sbt.internal.inc.IncrementalCompilerImpl.compileIncrementally(IncrementalCompilerImpl.scala:433)
Error:  sbt.internal.inc.IncrementalCompilerImpl.compile(IncrementalCompilerImpl.scala:137)
Error:  sbt.Defaults$.compileIncrementalTaskImpl(Defaults.scala:2443)
Error:  sbt.Defaults$.$anonfun$compileIncrementalTask$2(Defaults.scala:2393)
Error:  sbt.internal.server.BspCompileTask$.$anonfun$compute$1(BspCompileTask.scala:41)
Error:  sbt.internal.io.Retry$.apply(Retry.scala:47)
Error:  sbt.internal.io.Retry$.apply(Retry.scala:29)
Error:  sbt.internal.io.Retry$.apply(Retry.scala:24)
Error:  sbt.internal.server.BspCompileTask$.compute(BspCompileTask.scala:41)
Error:  sbt.Defaults$.$anonfun$compileIncrementalTask$1(Defaults.scala:2391)
Error:  scala.Function1.$anonfun$compose$1(Function1.scala:49)
Error:  sbt.internal.util.$tilde$greater.$anonfun$$u2219$1(TypeFunctions.scala:63)
Error:  sbt.std.Transform$$anon$4.work(Transform.scala:69)
Error:  sbt.Execute.$anonfun$submit$2(Execute.scala:283)
Error:  sbt.internal.util.ErrorHandling$.wideConvert(ErrorHandling.scala:24)
Error:  sbt.Execute.work(Execute.scala:292)
Error:  sbt.Execute.$anonfun$submit$1(Execute.scala:283)
Error:  sbt.ConcurrentRestrictions$$anon$4.$anonfun$submitValid$1(ConcurrentRestrictions.scala:265)
Error:  sbt.CompletionService$$anon$2.call(CompletionService.scala:65)
Error:  java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
Error:  java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:572)
Error:  java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
Error:  java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
Error:  java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
Error:  java.base/java.lang.Thread.run(Thread.java:1583)

[WojciechMazur]

Bisect points to b4a802a

Minimization:

//> using options -Ykind-projector:underscores

trait PatchCollectionWithOptionCollectionRuleModule { self: Derivation =>
  protected object PatchCollectionWithOptionCollectionRule extends Rule {
    def expand[Patch, A]: DerivationResult[ExpansionResult[A]] = {
      // given Type[A] = ??? 
      Type[A] match {
        case TotallyOrPartiallyBuildIterable(_) => ??? // couses crash, for some reason it compiles even if not given Type[A]
        case _                                  => ???
      }
    }
  }
}
 
trait Derivation:
  trait DerivationResult[+A]
  
  abstract protected class Rule:
    def expand[From, To]: DerivationResult[ExpansionResult[To]]
  sealed trait ExpansionResult[+A]

  final protected type Type[A] = scala.quoted.Type[A]
  object Type:
    final def apply[A]: Type[A] = ???

  final protected type Existential[F[_]] = Existential.Bounded[Nothing, Any, F]
  protected object Existential:
    sealed trait Bounded[L, U >: L, F[_ >: L <: U]]

  abstract protected class TotallyOrPartiallyBuildIterable[Collection, Item]
  object TotallyOrPartiallyBuildIterable:
    def unapply[M](implicit M: Type[M]): Option[Existential[TotallyOrPartiallyBuildIterable[M, *]]] = ???