No source root found for `.../modules/core/shared/src/main/scala-3/io/circe/Derivation.scala`

[nikololiahim]

I don't know if this affects only circe or any code that uses the derives keyword.

To reproduce:

1. Clone this gist.
2. (idk if this affects anything) move User.scala to src/main/scala folder and UserTest.scala to src/test/scala folder.
3. Run sbt clean coverage test coverageReport

Problem

The command fails with:

[error] java.lang.RuntimeException: No source root found for '/home/nikololiahim/scala/scoverage-bug/modules/core/shared/src/main/scala-3/io/circe/Derivation.scala' (source roots: '/home/nikololiahim/scala/scoverage-bug/src/main/scala/')
[error]         at scoverage.reporter.BaseReportWriter.relativeSource(BaseReportWriter.scala:35)
[error]         at scoverage.reporter.BaseReportWriter.relativeSource(BaseReportWriter.scala:23)
[error]         at scoverage.reporter.ScoverageHtmlWriter.classRow(ScoverageHtmlWriter.scala:249)
[error]         at scoverage.reporter.ScoverageHtmlWriter.$anonfun$classesTable$2(ScoverageHtmlWriter.scala:239)
[error]         at scala.collection.immutable.List.map(List.scala:293)
[error]         at scoverage.reporter.ScoverageHtmlWriter.classesTable(ScoverageHtmlWriter.scala:239)
[error]         at scoverage.reporter.ScoverageHtmlWriter.overview(ScoverageHtmlWriter.scala:460)
[error]         at scoverage.reporter.ScoverageHtmlWriter.write(ScoverageHtmlWriter.scala:65)
[error]         at scoverage.ScoverageSbtPlugin$.writeReports(ScoverageSbtPlugin.scala:324)
[error]         at scoverage.ScoverageSbtPlugin$.$anonfun$coverageReport0$1(ScoverageSbtPlugin.scala:220)
[error]         at scoverage.ScoverageSbtPlugin$.$anonfun$coverageReport0$1$adapted(ScoverageSbtPlugin.scala:195)
[error]         at scala.Function1.$anonfun$compose$1(Function1.scala:49)
[error]         at sbt.internal.util.$tilde$greater.$anonfun$$u2219$1(TypeFunctions.scala:62)
[error]         at sbt.std.Transform$$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:539)
[error]         at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
[error]         at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
[error]         at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
[error]         at java.base/java.lang.Thread.run(Thread.java:833)
[error] (coverageReport) No source root found for '/home/nikololiahim/scala/scoverage-bug/modules/core/shared/src/main/scala-3/io/circe/Derivation.scala' (source roots: '/home/nikololiahim/scala/scoverage-bug/src/main/scala/')

[ckipp01]

Thanks for the report @nikololiahim. Can you verify if the behavior is the same or different if you use 2.13.8. If it's not then it would be a problem in the actual Scala 3 compiler and we can move this issue over there.

[nikololiahim]

@ckipp01 Just tried with 2.13.8, seems to work correctly. I had to rewrite the code a bit:
User.scala

import io.circe._
import io.circe.generic.semiauto._

case class User(name: String, address: Address)
case class Address(country: String, city: String)

object User {
  implicit val userDecoder: Codec[User] = deriveCodec
  implicit val addrDecoder: Codec[Address] = deriveCodec
  def fromString(s: String): Option[User] = {
    s.split(",[ ]?") match {
      case Array(name, country, city) =>
        Some(User(name, Address(country, city)))
      case _ => None
    }
  }
}

And also add

"io.circe" %% "circe-generic-extras" % "0.14.2",

to build.sbt.

Seems like the problem is indeed tied to the derives keyword.

[ckipp01]

Gotcha, since this works for 2.13, are you then able to create an issue for this over at https://github.com/lampepfl/dotty/issues since I believe it will actually need to be fixed over there.

[nikololiahim]

@ckipp01 Should I copy it as is or should I reword it somehow?

[ckipp01]

You can just copy and just ensure that you have a minimal reproduction.

[nikololiahim]

seems like it was already reported: scala/scala3#15490

[ckipp01]

seems like it was already reported: scala/scala3#15490

Ah, perfect. I totally missed that.

[rochala]

@ckipp01 I checked this issue on dotty side and the generation looks to be working as intended. I closed the issue as scoverage.coverage contained derived methods and whole test project passed and compiled under -coverage-out:. flag. The problem is also not connected to this issue scala/scala3#15490 as it is about coverage data generated from macros which led to misleading data.

[nikololiahim]

The issue is still present with Scala 3.2.1-RC1.

[ruippeixotog]

This issue seems to be preventing PureConfig from enabling coverage on Scala 3 (pureconfig/pureconfig#1387).

[z4f1r0v]

Same thing with Scala 3.2.0 and circeVersion 0.15.0-M1

[ckipp01]

Note that this is probably the same issue as in #458 and I believe should be fixed by the work in scala/scala3#16235.