java.lang.VerifyError: Constructor must call super() or this() before return

[maloku]

Compiler version

scala version: 3.2.1

Minimized code

This is the minimal code I could get which reproduces the issue when -coverage-out:target/cov

//SomeValue.scala
package coveragebug


import scala.collection.immutable.ArraySeq
import scala.reflect.ClassTag

opaque type SomeValue = Boolean | BooleanArray //some more types

object SomeValue {
  def apply(value: Boolean | BooleanArray): SomeValue = value
}

extension (sv: SomeValue)
  def valueType: ValueType[?] = sv match
    case _:Boolean       => ValueType.booleanType
    case _: BooleanArray => ValueType.booleanArrayType
sealed trait WrappedBooleanArray {
  type U
  type V = ArraySeq[U]

  def value: V
}

final case class BooleanArray(override val value: ArraySeq[Boolean]) extends WrappedBooleanArray {
  override type U = Boolean
}
sealed trait ValueType[U] {

  def boo: Int
  //some other methods
}
sealed abstract class ArrayType[T: ValueType: ClassTag] extends ValueType[ArraySeq[T]]:
  private val sn = summon[ValueType[T]]
  override def boo: Int  = sn.boo + 1
end ArrayType


object ValueType {
  //some more givens

  given booleanType: ValueType[Boolean] with {
    def boo = 1

  }

  given booleanArrayType: ArrayType[Boolean] with {
    //some other methods
  }
}

It happens only when someArray.valueType

//SomeValueSpec.scala  in test sources
import org.scalatest.flatspec.AnyFlatSpec
import scala.collection.immutable.ArraySeq
import scala.reflect.ClassTag


class SomeValueSpec extends AnyFlatSpec {
  "Test" should "not crash" in {

    val someValue: SomeValue = SomeValue(false)
    val someArray: SomeValue = SomeValue(BooleanArray(ArraySeq(false, true)))
    someValue.valueType
    someArray.valueType

  }
}

//build.sbt
ThisBuild / version := "0.1.0-SNAPSHOT"

ThisBuild / scalaVersion := "3.2.1"

lazy val root = (project in file("."))
  .settings(
    name := "coveragebug",
    scalacOptions ++= Seq("-coverage-out", "target/cov"),
    libraryDependencies ++= Seq(
      "org.scalatest"   %% "scalatest"       % "3.2.14" % Test
    )
  )

Output (click arrow to expand)

```Scala [info] welcome to sbt 1.8.0 (GraalVM Community Java 11.0.17) ... [info] SomeValueSpec: [info] Test [info] coveragebug.SomeValueSpec *** ABORTED *** [info] java.lang.VerifyError: Constructor must call super() or this() before return [info] Exception Details: [info] Location: [info] coveragebug/ValueType$booleanArrayType$.()V @0: return [info] Reason: [info] Error exists in the bytecode [info] Bytecode: [info] 0000000: b1 [info] at coveragebug.SomeValue$package$.valueType(SomeValue.scala:16) [info] at coveragebug.SomeValueSpec.testFun$proxy1$1(SomeValueSpec.scala:18) [info] at coveragebug.SomeValueSpec.$init$$$anonfun$1(SomeValueSpec.scala:13) [info] at org.scalatest.Transformer.apply$$anonfun$1(Transformer.scala:22) [info] at org.scalatest.OutcomeOf.outcomeOf(OutcomeOf.scala:85) [info] at org.scalatest.OutcomeOf.outcomeOf$(OutcomeOf.scala:31) [info] at org.scalatest.OutcomeOf$.outcomeOf(OutcomeOf.scala:104) [info] at org.scalatest.Transformer.apply(Transformer.scala:22) [info] at org.scalatest.Transformer.apply(Transformer.scala:21) [info] at org.scalatest.flatspec.AnyFlatSpecLike$$anon$5.apply(AnyFlatSpecLike.scala:1697) [info] ... [error] java.lang.VerifyError: Constructor must call super() or this() before return [error] Exception Details: [error] Location: [error] coveragebug/ValueType$booleanArrayType$.()V @0: return [error] Reason: [error] Error exists in the bytecode [error] Bytecode: [error] 0000000: b1 [error] [error] at coveragebug.SomeValue$package$.valueType(SomeValue.scala:16) [error] at coveragebug.SomeValueSpec.testFun$proxy1$1(SomeValueSpec.scala:18) [error] at coveragebug.SomeValueSpec.$init$$$anonfun$1(SomeValueSpec.scala:13) [error] at org.scalatest.Transformer.apply$$anonfun$1(Transformer.scala:22) [error] at org.scalatest.OutcomeOf.outcomeOf(OutcomeOf.scala:85) [error] at org.scalatest.OutcomeOf.outcomeOf$(OutcomeOf.scala:31) [error] at org.scalatest.OutcomeOf$.outcomeOf(OutcomeOf.scala:104) [error] at org.scalatest.Transformer.apply(Transformer.scala:22) [error] at org.scalatest.Transformer.apply(Transformer.scala:21) [error] at org.scalatest.flatspec.AnyFlatSpecLike$$anon$5.apply(AnyFlatSpecLike.scala:1697) [error] at org.scalatest.TestSuite.withFixture(TestSuite.scala:196) [error] at org.scalatest.TestSuite.withFixture$(TestSuite.scala:138) [error] at org.scalatest.flatspec.AnyFlatSpec.withFixture(AnyFlatSpec.scala:1685) [error] at org.scalatest.flatspec.AnyFlatSpecLike.invokeWithFixture$1(AnyFlatSpecLike.scala:1703) [error] at org.scalatest.flatspec.AnyFlatSpecLike.runTest$$anonfun$1(AnyFlatSpecLike.scala:1707) [error] at org.scalatest.SuperEngine.runTestImpl(Engine.scala:306) [error] at org.scalatest.flatspec.AnyFlatSpecLike.runTest(AnyFlatSpecLike.scala:1707) [error] at org.scalatest.flatspec.AnyFlatSpecLike.runTest$(AnyFlatSpecLike.scala:51) [error] at coveragebug.SomeValueSpec.org$scalatest$BeforeAndAfter$$super$runTest(SomeValueSpec.scala:12) [error] at org.scalatest.BeforeAndAfter.runTest(BeforeAndAfter.scala:213) [error] at org.scalatest.BeforeAndAfter.runTest$(BeforeAndAfter.scala:118) [error] at coveragebug.SomeValueSpec.runTest(SomeValueSpec.scala:12) [error] at org.scalatest.flatspec.AnyFlatSpecLike.runTests$$anonfun$1(AnyFlatSpecLike.scala:1765) [error] at org.scalatest.SuperEngine.traverseSubNodes$1$$anonfun$1(Engine.scala:413) [error] at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15) [error] at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10) [error] at scala.collection.immutable.List.foreach(List.scala:333) [error] at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:429) [error] at org.scalatest.SuperEngine.runTestsInBranch(Engine.scala:390) [error] at org.scalatest.SuperEngine.traverseSubNodes$1$$anonfun$1(Engine.scala:427) [error] at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15) [error] at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10) [error] at scala.collection.immutable.List.foreach(List.scala:333) [error] at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:429) [error] at org.scalatest.SuperEngine.runTestsInBranch(Engine.scala:396) [error] at org.scalatest.SuperEngine.runTestsImpl(Engine.scala:475) [error] at org.scalatest.flatspec.AnyFlatSpecLike.runTests(AnyFlatSpecLike.scala:1765) [error] at org.scalatest.flatspec.AnyFlatSpecLike.runTests$(AnyFlatSpecLike.scala:51) [error] at org.scalatest.flatspec.AnyFlatSpec.runTests(AnyFlatSpec.scala:1685) [error] at org.scalatest.Suite.run(Suite.scala:1114) [error] at org.scalatest.Suite.run$(Suite.scala:564) [error] at org.scalatest.flatspec.AnyFlatSpec.org$scalatest$flatspec$AnyFlatSpecLike$$super$run(AnyFlatSpec.scala:1685) [error] at org.scalatest.flatspec.AnyFlatSpecLike.run$$anonfun$1(AnyFlatSpecLike.scala:1810) [error] at org.scalatest.SuperEngine.runImpl(Engine.scala:535) [error] at org.scalatest.flatspec.AnyFlatSpecLike.run(AnyFlatSpecLike.scala:1810) [error] at org.scalatest.flatspec.AnyFlatSpecLike.run$(AnyFlatSpecLike.scala:51) [error] at coveragebug.SomeValueSpec.org$scalatest$BeforeAndAfter$$super$run(SomeValueSpec.scala:12) [error] at org.scalatest.BeforeAndAfter.run(BeforeAndAfter.scala:273) [error] at org.scalatest.BeforeAndAfter.run$(BeforeAndAfter.scala:118) [error] at coveragebug.SomeValueSpec.org$scalatest$BeforeAndAfterAll$$super$run(SomeValueSpec.scala:12) [error] at org.scalatest.BeforeAndAfterAll.liftedTree1$1(BeforeAndAfterAll.scala:213) [error] at org.scalatest.BeforeAndAfterAll.run(BeforeAndAfterAll.scala:217) [error] at org.scalatest.BeforeAndAfterAll.run$(BeforeAndAfterAll.scala:135) [error] at coveragebug.SomeValueSpec.run(SomeValueSpec.scala:12) [error] at org.scalatest.tools.Framework.org$scalatest$tools$Framework$$runSuite(Framework.scala:321) [error] at org.scalatest.tools.Framework$ScalaTestTask.execute(Framework.scala:517) [error] at sbt.TestRunner.runTest$1(TestFramework.scala:147) [error] at sbt.TestRunner.run(TestFramework.scala:162) [error] at sbt.TestFramework$$anon$3$$anonfun$$lessinit$greater$1.$anonfun$apply$1(TestFramework.scala:330) [error] at sbt.TestFramework$.sbt$TestFramework$$withContextLoader(TestFramework.scala:290) [error] at sbt.TestFramework$$anon$3$$anonfun$$lessinit$greater$1.apply(TestFramework.scala:330) [error] at sbt.TestFramework$$anon$3$$anonfun$$lessinit$greater$1.apply(TestFramework.scala:330) [error] at sbt.TestFunction.apply(TestFramework.scala:342) [error] at sbt.Tests$.$anonfun$toTask$1(Tests.scala:435) [error] at sbt.std.Transform$$anon$3.$anonfun$apply$2(Transform.scala:46) [error] at sbt.std.Transform$$anon$4.work(Transform.scala:68) [error] at sbt.Execute.$anonfun$submit$2(Execute.scala:282) [error] at sbt.internal.util.ErrorHandling$.wideConvert(ErrorHandling.scala:23) [error] at sbt.Execute.work(Execute.scala:291) [error] at sbt.Execute.$anonfun$submit$1(Execute.scala:282) [error] at sbt.ConcurrentRestrictions$$anon$4.$anonfun$submitValid$1(ConcurrentRestrictions.scala:265) [error] at sbt.CompletionService$$anon$2.call(CompletionService.scala:64) [error] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) [error] at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) [error] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) [error] at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) [error] at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) [error] at java.base/java.lang.Thread.run(Thread.java:829) [error] (Test / executeTests) java.lang.VerifyError: Constructor must call super() or this() before return [error] Exception Details: [error] Location: [error] coveragebug/ValueType$booleanArrayType$.()V @0: return [error] Reason: [error] Error exists in the bytecode [error] Bytecode: [error] 0000000: b1 ```

[TheElectronWill]

Thank you for the report and the reproducible example!
I've tested that the crash is fixed by dotty 3.2.2-RC1 and above (thanks to #16235)