NoSuchElementException: key not found for Dynamic Cross Multi Modules build

[asarkar]

.
├── prime-factors
│   ├── package.mill
│   ├── build.sbt
│   ├── jmh
│   │   └── src
│   │       └── A.scala
│   └── src
│       ├── main
│       │   └── scala
│       │       └── B.scala
│       └── test
│           └── scala
│               └── BTest.scala
├── <more directories>
└── build.mill

build.mill

package build

import mill._, scalalib._, scalafmt._
import $packages._

def isSbtProject(p: os.Path) = os.exists(p / "build.sbt")
def moduleNames = interp.watchValue(
    os.walk(millSourcePath, !isSbtProject(_), maxDepth = 1)
      .map(_.last)
)

object modules extends Cross[MyModule](moduleNames)

trait MyModule extends SbtModule with Cross.Module[String] with ScalafmtModule {
  outer =>

  val scalaVersion = "3.4.2"

  // Ends with 'modules' that need to be removed
  def millSourcePath = super.millSourcePath / os.up / crossValue

  def scalacOptions: T[Seq[String]] = Seq(
    "-encoding", "UTF-8",
    ...
  )

  object test extends SbtTests with TestModule.ScalaTest {
   val scalatestVersion = "3.2.19"
   val scalacheckVersion = "3.2.19.0"
   def scalacOptions: T[Seq[String]] = Seq("-encoding", "UTF-8")

   def ivyDeps = Agg(
    ivy"org.scalatest::scalatest:$scalatestVersion",
     ...
    )
  }
}

prime-factors/package.mill

package build.`prime-factors`

import mill._, scalalib._
import $ivy.`com.lihaoyi::mill-contrib-jmh:`
import contrib.jmh.JmhModule

object jmh extends ScalaModule with JmhModule {
    val scalaVersion = build.modules(build.`prime-factors`).scalaVersion
    def scalacOptions = build.modules(build.`prime-factors`).scalacOptions
    def jmhCoreVersion = "1.37"
    def moduleDeps = build.modules(build.`prime-factors`).test.moduleDeps
}

java.util.NoSuchElementException: key not found: List(prime-factors)
    scala.collection.MapOps.default(Map.scala:289)
    scala.collection.MapOps.default$(Map.scala:288)
    scala.collection.AbstractMapView.default(MapView.scala:187)
    scala.collection.MapOps.apply(Map.scala:176)
    scala.collection.MapOps.apply$(Map.scala:175)
    scala.collection.AbstractMapView.apply(MapView.scala:187)
    mill.define.Cross.apply(Cross.scala:373)
    build_.prime$minusfactors.package_$jmh$.<init>(package.mill:8)
    build_.prime$minusfactors.package_.jmh$lzycompute$1(package.mill:24)
    build_.prime$minusfactors.package_.jmh(package.mill:24)
    ...

Given the stacktrace, it appears that the module name is "normalized" by replacing the - with $minus, but that's just a guess, since I've no way of looking into the contents of the map.
Using Mill 0.12.3.

[lihaoyi]

@asarkar looks like you want build.modules("prime-factors")

[asarkar]

I can confirm this to be working. One question regarding dynamic cross modules: If I wanted to add a special dependency based on the module name/path, how'd I do it? For example, say only a handful of dynamic modules need that dependency and the others don't.

[lihaoyi]

@asarkar you can use def ivyDeps = if (crossValue == "???") Task{...} else {...} where ??? is the cross value you want to special case

[asarkar]

What's Task, something like ivy"org.scalatest::scalatest:$scalatestVersion"? Do you, perhaps, have an example of this in the codebase (I checked the docs and there's no mention of conditional dynamic cross module setup)

[lihaoyi]

def ivyDeps = if (crossValue == "???") Task{Seq(ivy"...")} else Task{Seq(ivy"...")} 

[asarkar]

Thank you for the clarification. For future reference of anyone wanting to do the same, I ended up with the following.

val commonDeps = Seq(ivy"org.scalatest::scalatest:$scalatestVersion")
val scDep =  Seq(ivy"org.scalatestplus::scalacheck-1-18:$scalacheckVersion")
def ivyDeps = Task{commonDeps ++ (if (crossValue == "simple-linked-list") scDep else Seq())}

[lihaoyi]

I'm not actually sure what you are trying to do here, so perhaps you could elaborate. Your code is incomplete so I can't run it, and you provided no explanation

[asarkar]

I'm trying to set up the immediate subdirectories as dynamic cross modules. One of these has a jmh folder that should be a module of its own, similar to modules[`prime-factors`].test. Does that make sense?

[lihaoyi]

@asarkar what keys end in the Cross module is entirely under your control based on what you pass to extends Cross[MyModule](moduleNames). If you don't want [jmh] to be in there, just filter it out when computing moduleNames