Generate the `Segments` list at definition time rather than discovery time, by propagating implicits throughout the tree of nested `mill.Module`s

This currently adds some annoying boilerplate to the definition of cross/abstract modules, which can probably be removed using Macros.

The `Segments` mapping generated by discovery is still present and used in a few places, though it will be removed

2 files changed, 8 insertions, 8 deletions

diff --git a/scalalib/src/main/scala/mill/scalalib/GenIdea.scala b/scalalib/src/main/scala/mill/scalalib/GenIdea.scala
index e9ba76b5..5c3d8d71 100644
--- a/scalalib/src/main/scala/mill/scalalib/GenIdea.scala
+++ b/scalalib/src/main/scala/mill/scalalib/GenIdea.scala
@@ -2,7 +2,7 @@ package mill.scalalib
 
 import ammonite.ops._
 import mill.define.Target
-import mill.discover.Mirror.Segment
+import mill.define.Segment
 import mill.discover.{Discovered, Mirror}
 import mill.eval.{Evaluator, PathRef}
 import mill.util.Ctx.{LoaderCtx, LogCtx}
@@ -28,7 +28,7 @@ object GenIdea {
 
     val modules = Mirror
       .traverse(evaluator.mapping.base, evaluator.mapping.mirror){ (h, p) =>
-        h.node(evaluator.mapping.base, p.reverse.map{case Mirror.Segment.Cross(vs) => vs.toList case _ => Nil}.toList) match {
+        h.node(evaluator.mapping.base, p.reverse.map{case Segment.Cross(vs) => vs.toList case _ => Nil}.toList) match {
           case m: Module => Seq(p -> m)
           case _ => Nil
         }
@@ -100,7 +100,7 @@ object GenIdea {
     (Seq.fill(r.ups)("..") ++ r.segments).mkString("/")
   }
 
-  def moduleName(p: Seq[Mirror.Segment]) = p.foldLeft(StringBuilder.newBuilder) {
+  def moduleName(p: Seq[Segment]) = p.foldLeft(StringBuilder.newBuilder) {
     case (sb, Segment.Label(s)) if sb.isEmpty => sb.append(s)
     case (sb, Segment.Cross(s)) if sb.isEmpty => sb.append(s.mkString("-"))
     case (sb, Segment.Label(s)) => sb.append(".").append(s)
diff --git a/scalalib/src/test/scala/mill/scalalib/HelloWorldTests.scala b/scalalib/src/test/scala/mill/scalalib/HelloWorldTests.scala
index fe313f8a..aaeb96c1 100644
--- a/scalalib/src/test/scala/mill/scalalib/HelloWorldTests.scala
+++ b/scalalib/src/test/scala/mill/scalalib/HelloWorldTests.scala
@@ -22,11 +22,11 @@ trait HelloWorldModule extends scalalib.Module {
 
 object HelloWorld extends TestUtil.BaseModule with HelloWorldModule
 object CrossHelloWorld extends TestUtil.BaseModule {
-  val cross =
-    for(v <- Cross("2.10.6", "2.11.11", "2.12.3", "2.12.4"))
-    yield new HelloWorldModule {
-      def scalaVersion = v
-    }
+  object cross extends CrossModule(HelloWorldCrossModule, "2.10.6", "2.11.11", "2.12.3", "2.12.4")
+  case class HelloWorldCrossModule(v: String, ctx0: Module.Ctx)
+  extends mill.Module()(ctx0) with HelloWorldModule {
+    def scalaVersion = v
+  }
 }
 
 object HelloWorldWithMain extends TestUtil.BaseModule with HelloWorldModule {