Change GenIdeaModule#ideaCompileOutput to match module localClasspath

[yankun1992]

I have two module:

object mio extends ScalaModule {
  override def scalaVersion = "3.2.1"

  override def moduleDeps: scala.Seq[JavaModule] = scala.Seq(mionative)
}

object mionative extends JavaModule {
  // define target to generate native jni library
  def compileNative : T[PathRef] = ???

  override def localClasspath: T[Seq[PathRef]] = T {
    super.localClasspath() :+ compileNative()
  }

}

When use

mill mio.run

it can load native library succeed but fail use idea run because

mill mill.scalalib.GenIdea/idea

use ideaCompileOutput to generate module classpath and it fix

  def ideaCompileOutput: T[PathRef] = T.persistent {
    PathRef(T.dest / "classes")
  }

Maybe we can change the return type of ideaCompileOutput to T[Seq[PathRef]] or change GenIdeaImpl#xmlFileLayout to integrate module localClasspath ?

[lefou]

GenIdeaModule.ideaCompileOutput is the path used by IDEA to write compilation output (class files) to. This content of this path is meant to be managed by IDEA.

Also, changing GenIdeaImpl.xmlFileLayout is not helpful, as we only generate config files and we can only use what Idea already supports. We especially have no way to trigger dedicated Mill targets, like your compileNative from within IDEA.

That being said, if your compileNative is mostly stable and does not need to re-run often (especially not more often than you re-generate the IDEA project), you could consider to return the compileNative result from resources instead of localClasspath. It still ends in localClasspath, but also IDEA will see it.

[yankun1992]

Thank you very much, it works!

[yankun1992]

By the way, I have developed a mill plugin to compile the jni code implemented by rust. The repository is mill-rust-jni. Wellcome to use!

[lefou]

Nice. Feel free to add your plugin the our documentation: https://com-lihaoyi.github.io/mill/mill/Thirdparty_Plugins.html

Also, as major Mill versions (e.g. 0.10.x or 0.9.x) are not binary compatible, it's a convention to add the Mill binary platform as a suffix to the published artifact name, e.g. _mill0.10. You can find details here: https://com-lihaoyi.github.io/mill/mill/Using_Plugins.html