Logical loops in moduleDeps

[tballard]

It appears that logical loops in moduleDeps are rewarded with a hearty stack trace as of 10.9. An error message with a list of the modules in the loop(s) would be the right thing, I suppose.

[lefou]

Can you please provide a reproduction?

[tballard]

Sure:

import mill.scalalib._
import mill.define.Task

object a extends ScalaModule() {
   override def moduleDeps = Seq(a)

   override def scalaVersion = "2.13.7"
}

> mill a.compile
yields:

Caused by: java.lang.StackOverflowError
	at ammonite.$file.build$a$.moduleDeps(build.sc:5)
	at mill.scalalib.JavaModule.recursiveModuleDeps(JavaModule.scala:155)
	at mill.scalalib.JavaModule.recursiveModuleDeps$(JavaModule.scala:154)
	at ammonite.$file.build$a$.recursiveModuleDeps(build.sc:4)
	at mill.scalalib.JavaModule.transitiveModuleDeps(JavaModule.scala:160)
	at mill.scalalib.JavaModule.transitiveModuleDeps$(JavaModule.scala:159)
	at ammonite.$file.build$a$.transitiveModuleDeps(build.sc:4)
	at mill.scalalib.JavaModule.$anonfun$recursiveModuleDeps$1(JavaModule.scala:155)
	at scala.collection.immutable.List.flatMap(List.scala:293)
	at scala.collection.immutable.List.flatMap(List.scala:79)
	at mill.scalalib.JavaModule.recursiveModuleDeps(JavaModule.scala:155)
	at mill.scalalib.JavaModule.recursiveModuleDeps$(JavaModule.scala:154)
	at ammonite.$file.build$a$.recursiveModuleDeps(build.sc:4)
	at mill.scalalib.JavaModule.transitiveModuleDeps(JavaModule.scala:160)
	at mill.scalalib.JavaModule.transitiveModuleDeps$(JavaModule.scala:159)
	at ammonite.$file.build$a$.transitiveModuleDeps(build.sc:4)
	at mill.scalalib.JavaModule.$anonfun$recursiveModuleDeps$1(JavaModule.scala:155)
	at scala.collection.immutable.List.flatMap(List.scala:293)
	at scala.collection.immutable.List.flatMap(List.scala:79)
	at mill.scalalib.JavaModule.recursiveModuleDeps(JavaModule.scala:155)
	at mill.scalalib.JavaModule.recursiveModuleDeps$(JavaModule.scala:154)
	at ammonite.$file.build$a$.recursiveModuleDeps(build.sc:4)
	at mill.scalalib.JavaModule.transitiveModuleDeps(JavaModule.scala:160)
	at mill.scalalib.JavaModule.transitiveModuleDeps$(JavaModule.scala:159)
	at ammonite.$file.build$a$.transitiveModuleDeps(build.sc:4)
	at mill.scalalib.JavaModule.$anonfun$recursiveModuleDeps$1(JavaModule.scala:155)
	at scala.collection.immutable.List.flatMap(List.scala:293)
	at scala.collection.immutable.List.flatMap(List.scala:79)
	at mill.scalalib.JavaModule.recursiveModuleDeps(JavaModule.scala:155)
	at mill.scalalib.JavaModule.recursiveModuleDeps$(JavaModule.scala:154)
	at ammonite.$file.build$a$.recursiveModuleDeps(build.sc:4)
	at mill.scalalib.JavaModule.transitiveModuleDeps(JavaModule.scala:160)
	at mill.scalalib.JavaModule.transitiveModuleDeps$(JavaModule.scala:159)
	at ammonite.$file.build$a$.transitiveModuleDeps(build.sc:4)
	at mill.scalalib.JavaModule.$anonfun$recursiveModuleDeps$1(JavaModule.scala:155)
	at scala.collection.immutable.List.flatMap(List.scala:293)
	at scala.collection.immutable.List.flatMap(List.scala:79)
	at mill.scalalib.JavaModule.recursiveModuleDeps(JavaModule.scala:155)

until the stack chokes