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Published 20 hours ago • verified publisher icon scala

transform.PatternMatcher crash on extracting exported macro-generated unapply

Open Adam-Vandervorst opened this issue 1 year ago • 1 comments

Compiler version

3.2.1-RC1-bin-20220904-b5fea82-NIGHTLY

Minimized code

I failed to minimize the code and published the code (sbt > test).

Usage site:

println(SizedVector.unapply(v1)) // works fine, prints `(2,3)`
val SizedVector(a, b) = v1 // crashes with the message at the end
println(s"a: $a, b: $b")

Export site:

object SizedVector:
  export be.adamv.macroloop.collection.TupleConstructors.{vectorApply as apply, vectorUnapply as unapply}

Definition site:

object TupleConstructors:
  import be.adamv.macroloop.collection.macros.*
  import compiletime.ops.int.S

  type RepeatN[T, I <: Int] <: Tuple = I match
    case 0 => EmptyTuple
    case S[n] => T *: RepeatN[T, n]

  transparent inline def vectorUnapply[N <: Int, A](inline v: SizedVector[N, A]): RepeatN[A, N] =
    ${ destructVectorImpl[N, A]('v) }

Macro definition site:

def destructVectorImpl[N <: Int : Type, A: Type](elementse: Expr[SizedVector[N, A]])(using Quotes): Expr[RepeatN[A, N]] =
  val size = Type.valueOfConstant[N].get
  val elements = Seq.tabulate(size)(i => '{ $elementse.data(${ Expr(i) }) })

  Expr.ofTupleFromSeq(elements).asInstanceOf[Expr[RepeatN[A, N]]]

Output (click arrow to expand)

[IJ]test
[info] compiling 3 Scala sources to /home/adamv/IdeaProjects/MacroLoop/collection/target/scala-3.2.1-RC1-bin-20220904-b5fea82-NIGHTLY/test-classes ...
[warn] -- Warning: /home/adamv/IdeaProjects/MacroLoop/collection/src/test/scala/VectorBasic.scala:30:19 
[warn] 30 |    val SizedVector(a, b) = v1
[warn]    |        ^^^^^^^^^^^^^^^^^^^^^^
[warn]    |pattern binding uses refutable extractor `{
[warn]    |  final class $anon() extends Object() {
[warn]    |    def unapply(v: be.adamv.macroloop.collection.SizedVector[(2 : Int), Int]): 
[warn]    |      be.adamv.macroloop.collection.TupleConstructors.RepeatN[Int, (2 : Int)]
[warn]    |     = Tuple2.apply[Int, Int](v.data.apply(0), v.data.apply(1))
[warn]    |  }
[warn]    |  new Object {...}()
[warn]    |}`
[warn]    |
[warn]    |If this usage is intentional, this can be communicated by adding `: @unchecked` after the expression,
[warn]    |which may result in a MatchError at runtime.
[warn]    |This patch can be rewritten automatically under -rewrite -source 3.2-migration.
scala.MatchError: List() (of class scala.collection.immutable.Nil$) while running MegaPhase{crossVersionChecks, protectedAccessors, extmethods, uncacheGivenAliases, elimByName, hoistSuperArgs, forwardDepChecks, specializeApplyMethods, tryCatchPatterns, patternMatcher} on /home/adamv/IdeaProjects/MacroLoop/collection/src/test/scala/VectorBasic.scala
[info] exception occurred while compiling /home/adamv/IdeaProjects/MacroLoop/collection/src/test/scala/CrossBasic.scala, /home/adamv/IdeaProjects/MacroLoop/collection/src/test/scala/MatrixBasic.scala, /home/adamv/IdeaProjects/MacroLoop/collection/src/test/scala/VectorBasic.scala
scala.MatchError: List() (of class scala.collection.immutable.Nil$) while compiling /home/adamv/IdeaProjects/MacroLoop/collection/src/test/scala/CrossBasic.scala, /home/adamv/IdeaProjects/MacroLoop/collection/src/test/scala/MatrixBasic.scala, /home/adamv/IdeaProjects/MacroLoop/collection/src/test/scala/VectorBasic.scala
[error] ## Exception when compiling 3 sources to /home/adamv/IdeaProjects/MacroLoop/collection/target/scala-3.2.1-RC1-bin-20220904-b5fea82-NIGHTLY/test-classes
[error] scala.MatchError: List() (of class scala.collection.immutable.Nil$)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.matchArgsPatternPlan$1(PatternMatcher.scala:265)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.matchArgsComponentsPlan$1(PatternMatcher.scala:260)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.matchArgsPlan$1(PatternMatcher.scala:271)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.unapplyPlan$1$$anonfun$1(PatternMatcher.scala:363)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.letAbstract(PatternMatcher.scala:112)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.unapplyPlan$1(PatternMatcher.scala:383)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.patternPlan(PatternMatcher.scala:420)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.caseDefPlan(PatternMatcher.scala:456)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.matchPlan$$anonfun$1$$anonfun$1(PatternMatcher.scala:463)
[error] scala.collection.immutable.List.foldRight(List.scala:352)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.matchPlan$$anonfun$1(PatternMatcher.scala:463)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.letAbstract(PatternMatcher.scala:112)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.matchPlan(PatternMatcher.scala:464)
[error] dotty.tools.dotc.transform.PatternMatcher$Translator.translateMatch(PatternMatcher.scala:1042)
[error] dotty.tools.dotc.transform.PatternMatcher.transformMatch(PatternMatcher.scala:45)
[error] dotty.tools.dotc.transform.MegaPhase.goMatch(MegaPhase.scala:785)
[error] dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:366)
[error] dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:427)
[error] dotty.tools.dotc.transform.MegaPhase.mapValDef$1(MegaPhase.scala:234)
[error] dotty.tools.dotc.transform.MegaPhase.transformNamed$1(MegaPhase.scala:239)
[error] dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:425)
[error] dotty.tools.dotc.transform.MegaPhase.loop$2(MegaPhase.scala:444)
[error] dotty.tools.dotc.transform.MegaPhase.transformBlock(MegaPhase.scala:449)
[error] dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:298)
[error] dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:427)
[error] dotty.tools.dotc.transform.MegaPhase.recur$1(MegaPhase.scala:459)
[error] dotty.tools.dotc.transform.MegaPhase.transformTrees(MegaPhase.scala:459)
[error] dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:279)
[error] dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:427)
[error] dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:278)
[error] dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:427)
[error] dotty.tools.dotc.transform.MegaPhase.loop$1(MegaPhase.scala:438)
[error] dotty.tools.dotc.transform.MegaPhase.transformStats(MegaPhase.scala:438)
[error] dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:359)
[error] dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:427)
[error] dotty.tools.dotc.transform.MegaPhase.transformNamed$1(MegaPhase.scala:255)
[error] dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:425)
[error] dotty.tools.dotc.transform.MegaPhase.loop$1(MegaPhase.scala:438)
[error] dotty.tools.dotc.transform.MegaPhase.transformStats(MegaPhase.scala:438)
[error] dotty.tools.dotc.transform.MegaPhase.mapPackage$1(MegaPhase.scala:379)
[error] dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:382)
[error] dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:427)
[error] dotty.tools.dotc.transform.MegaPhase.transformUnit(MegaPhase.scala:454)
[error] dotty.tools.dotc.transform.MegaPhase.run(MegaPhase.scala:466)
[error] dotty.tools.dotc.core.Phases$Phase.runOn$$anonfun$1(Phases.scala:316)
[error] scala.collection.immutable.List.map(List.scala:250)
[error] dotty.tools.dotc.core.Phases$Phase.runOn(Phases.scala:320)
[error] dotty.tools.dotc.Run.runPhases$1$$anonfun$1(Run.scala:233)
[error] scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
[error] scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
[error] scala.collection.ArrayOps$.foreach$extension(ArrayOps.scala:1328)
[error] dotty.tools.dotc.Run.runPhases$1(Run.scala:244)
[error] dotty.tools.dotc.Run.compileUnits$$anonfun$1(Run.scala:252)
[error] dotty.tools.dotc.Run.compileUnits$$anonfun$adapted$1(Run.scala:261)
[error] dotty.tools.dotc.util.Stats$.maybeMonitored(Stats.scala:68)
[error] dotty.tools.dotc.Run.compileUnits(Run.scala:261)
[error] dotty.tools.dotc.Run.compileSources(Run.scala:185)
[error] dotty.tools.dotc.Run.compile(Run.scala:169)
[error] dotty.tools.dotc.Driver.doCompile(Driver.scala:35)
[error] dotty.tools.xsbt.CompilerBridgeDriver.run(CompilerBridgeDriver.java:88)
[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$7(MixedAnalyzingCompiler.scala:192)
[error] scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:23)
[error] sbt.internal.inc.MixedAnalyzingCompiler.timed(MixedAnalyzingCompiler.scala:247)
[error] sbt.internal.inc.MixedAnalyzingCompiler.$anonfun$compile$4(MixedAnalyzingCompiler.scala:182)
[error] sbt.internal.inc.MixedAnalyzingCompiler.$anonfun$compile$4$adapted(MixedAnalyzingCompiler.scala:163)
[error] sbt.internal.inc.JarUtils$.withPreviousJar(JarUtils.scala:239)
[error] sbt.internal.inc.MixedAnalyzingCompiler.compileScala$1(MixedAnalyzingCompiler.scala:163)
[error] sbt.internal.inc.MixedAnalyzingCompiler.compile(MixedAnalyzingCompiler.scala:210)
[error] sbt.internal.inc.IncrementalCompilerImpl.$anonfun$compileInternal$1(IncrementalCompilerImpl.scala:528)
[error] sbt.internal.inc.IncrementalCompilerImpl.$anonfun$compileInternal$1$adapted(IncrementalCompilerImpl.scala:528)
[error] sbt.internal.inc.Incremental$.$anonfun$apply$5(Incremental.scala:177)
[error] sbt.internal.inc.Incremental$.$anonfun$apply$5$adapted(Incremental.scala:175)
[error] sbt.internal.inc.Incremental$$anon$2.run(Incremental.scala:461)
[error] sbt.internal.inc.IncrementalCommon$CycleState.next(IncrementalCommon.scala:116)
[error] sbt.internal.inc.IncrementalCommon$$anon$1.next(IncrementalCommon.scala:56)
[error] sbt.internal.inc.IncrementalCommon$$anon$1.next(IncrementalCommon.scala:52)
[error] sbt.internal.inc.IncrementalCommon.cycle(IncrementalCommon.scala:263)
[error] sbt.internal.inc.Incremental$.$anonfun$incrementalCompile$8(Incremental.scala:416)
[error] sbt.internal.inc.Incremental$.withClassfileManager(Incremental.scala:503)
[error] sbt.internal.inc.Incremental$.incrementalCompile(Incremental.scala:403)
[error] sbt.internal.inc.Incremental$.apply(Incremental.scala:169)
[error] sbt.internal.inc.IncrementalCompilerImpl.compileInternal(IncrementalCompilerImpl.scala:528)
[error] sbt.internal.inc.IncrementalCompilerImpl.$anonfun$compileIncrementally$1(IncrementalCompilerImpl.scala:482)
[error] sbt.internal.inc.IncrementalCompilerImpl.handleCompilationError(IncrementalCompilerImpl.scala:332)
[error] sbt.internal.inc.IncrementalCompilerImpl.compileIncrementally(IncrementalCompilerImpl.scala:420)
[error] sbt.internal.inc.IncrementalCompilerImpl.compile(IncrementalCompilerImpl.scala:137)
[error] sbt.Defaults$.compileIncrementalTaskImpl(Defaults.scala:2366)
[error] sbt.Defaults$.$anonfun$compileIncrementalTask$2(Defaults.scala:2316)
[error] sbt.internal.server.BspCompileTask$.$anonfun$compute$1(BspCompileTask.scala:30)
[error] sbt.internal.io.Retry$.apply(Retry.scala:46)
[error] sbt.internal.io.Retry$.apply(Retry.scala:28)
[error] sbt.internal.io.Retry$.apply(Retry.scala:23)
[error] sbt.internal.server.BspCompileTask$.compute(BspCompileTask.scala:30)
[error] sbt.Defaults$.$anonfun$compileIncrementalTask$1(Defaults.scala:2314)
[error] scala.Function1.$anonfun$compose$1(Function1.scala:49)
[error] sbt.internal.util.$tilde$greater.$anonfun$$u2219$1(TypeFunctions.scala:62)
[error] sbt.std.Transform$$anon$4.work(Transform.scala:68)
[error] sbt.Execute.$anonfun$submit$2(Execute.scala:282)
[error] sbt.internal.util.ErrorHandling$.wideConvert(ErrorHandling.scala:23)
[error] sbt.Execute.work(Execute.scala:291)
[error] sbt.Execute.$anonfun$submit$1(Execute.scala:282)
[error] sbt.ConcurrentRestrictions$$anon$4.$anonfun$submitValid$1(ConcurrentRestrictions.scala:265)
[error] sbt.CompletionService$$anon$2.call(CompletionService.scala:64)
[error] java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
[error] java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
[error] java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
[error] java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
[error] java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
[error] java.base/java.lang.Thread.run(Thread.java:833)

Adam-Vandervorst avatar Sep 07 '22 15:09 Adam-Vandervorst

For what it's worth, this does work:

// in main.scala
import compiletime.ops.int.S
type RepeatN[T, I <: Int] <: Tuple = I match
  case 0 => EmptyTuple
  case S[n] => T *: RepeatN[T, n]

abstract class Pair:
  val ar: Array[Int]

object Utils:
  inline def pairUnapply(p: Pair): RepeatN[Int, 2] =
    ${ impl('p) }

object Pair:
  export Utils.pairUnapply as unapply

@main def example =
  val p: Pair = new Pair:
    val ar = Array(1, 2)

  val Pair(x, y) = p
  println(x)

// in macro.scala
import scala.quoted.*

def impl(paire: Expr[Pair])(using Quotes): Expr[RepeatN[Int, 2]] =
  val els = Seq.tabulate(2)(i => '{ $paire.ar(${ Expr(i) }) })
  Expr.ofTupleFromSeq(els).asInstanceOf[Expr[RepeatN[Int, 2]]]

Adam-Vandervorst avatar Sep 07 '22 15:09 Adam-Vandervorst