Unexpected `NullPointerException` in sbt `unmanagedResources`

[4lex1v]

Hey bloop team!

I'm hitting a NullPointerException error when trying to generate bloop's config for the project. It works for all modules except one. After some investigation I've noticed that the error occurs because we have some additional resources configuration outside of module's root, e.g:

    Compile / unmanagedResources ++= Seq(
      file("file1.yml"),
      file("folder/file2.yaml"),
      ... etc
    ),

With the above setting, I'm getting the following error:

java.lang.NullPointerException stack trace

sbt:root> last
[debug] > Exec(bloopInstall, Some(521bc6d9-2a6e-41f3-ad9d-1eacfbe6aa7f), Some(CommandSource(console0)))
[debug] Evaluating tasks: checkBuildSources
[debug] Running task... Cancel: bloop.integrations.sbt.Offloader$$anon$1@330d557e, check cycles: false, forcegc: true
[debug] Evaluating tasks: analytics / bloopInstall, analyticsCli / bloopInstall, e2eTest / bloopInstall, clusterDeps / bloopInstall, bloopInstall
[debug] Running task... Cancel: bloop.integrations.sbt.Offloader$$anon$1@3e3d8e6c, check cycles: false, forcegc: true
[success] Generated .bloop\root-test.json
[success] Generated .bloop\analyticsCli-test.json
[success] Generated .bloop\clusterDeps-test.json
[success] Generated .bloop\e2eTest-test.json
[success] Generated .bloop\analytics-it.json
[success] Generated .bloop\analytics-test.json
[error] java.lang.NullPointerException
[error]         at bloop.config.util.ConfigUtil$.$anonfun$pathsOutsideRoots$2(ConfigUtil.scala:11)
[error]         at bloop.config.util.ConfigUtil$.$anonfun$pathsOutsideRoots$2$adapted(ConfigUtil.scala:8)
[error]         at scala.collection.LinearSeqOptimized.exists(LinearSeqOptimized.scala:95)
[error]         at scala.collection.LinearSeqOptimized.exists$(LinearSeqOptimized.scala:92)
[error]         at scala.collection.immutable.List.exists(List.scala:89)
[error]         at bloop.config.util.ConfigUtil$.$anonfun$pathsOutsideRoots$1(ConfigUtil.scala:8)
[error]         at bloop.config.util.ConfigUtil$.$anonfun$pathsOutsideRoots$1$adapted(ConfigUtil.scala:7)
[error]         at scala.collection.TraversableLike.$anonfun$filterImpl$1(TraversableLike.scala:256)
[error]         at scala.collection.Iterator.foreach(Iterator.scala:941)
[error]         at scala.collection.Iterator.foreach$(Iterator.scala:941)
[error]         at scala.collection.AbstractIterator.foreach(Iterator.scala:1429)
[error]         at scala.collection.IterableLike.foreach(IterableLike.scala:74)
[error]         at scala.collection.IterableLike.foreach$(IterableLike.scala:73)
[error]         at scala.collection.AbstractIterable.foreach(Iterable.scala:56)
[error]         at scala.collection.TraversableLike.filterImpl(TraversableLike.scala:255)
[error]         at scala.collection.TraversableLike.filterImpl$(TraversableLike.scala:249)
[error]         at scala.collection.AbstractTraversable.filterImpl(Traversable.scala:108)
[error]         at scala.collection.TraversableLike.filterNot(TraversableLike.scala:355)
[error]         at scala.collection.TraversableLike.filterNot$(TraversableLike.scala:355)
[error]         at scala.collection.AbstractTraversable.filterNot(Traversable.scala:108)
[error]         at bloop.config.util.ConfigUtil$.pathsOutsideRoots(ConfigUtil.scala:7)
[error]         at bloop.integrations.sbt.BloopDefaults$.$anonfun$bloopResourcesTask$2(SbtBloop.scala:1267)
[error]         at scala.Function1.$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$4.work(Transform.scala:67)
[error]         at sbt.Execute.$anonfun$submit$2(Execute.scala:281)
[error]         at sbt.internal.util.ErrorHandling$.wideConvert(ErrorHandling.scala:19)
[error]         at sbt.Execute.work(Execute.scala:290)
[error]         at sbt.Execute.$anonfun$submit$1(Execute.scala:281)
[error]         at sbt.ConcurrentRestrictions$$anon$4.$anonfun$submitValid$1(ConcurrentRestrictions.scala:178)

[error]         at sbt.CompletionService$$anon$2.call(CompletionService.scala:37)
[error]         at java.util.concurrent.FutureTask.run(FutureTask.java:266)
[error]         at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
[error]         at java.util.concurrent.FutureTask.run(FutureTask.java:266)
[error]         at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
[error]         at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
[error]         at java.lang.Thread.run(Thread.java:748)
[error] (analyticsCli / Compile / bloopGenerate) java.lang.NullPointerException
[error] Total time: 4 s, completed Aug 25, 2020 5:34:09 PM
[debug] > Exec(shell, None, None)
[debug] Evaluating tasks: checkBuildSources
[debug] Running task... Cancel: bloop.integrations.sbt.Offloader$$anon$1@31406eab, check cycles: false, forcegc: true

Changing the value of this setting to something like Seq.empty (i.e set analyticsCli / Compile / unmanagedResources := Seq.empty) addresses the problem and bloopInstall works.

If this would be important i'm using bloop 1.4.3, sbt 1.3.13 on Windows 10.

Please let me know if you need more details.

[jvican]

Thanks for the report! This should be an easy to fix, could you submit a fix in ConfigUtil so that nulls are correctly dealt with? I don't understand why the nulls are thrown but I wouldn't be surprised if it has anything to do with the relative file paths you have in your unmanagedResources.