Remove targets generation in Mirror, in favor of just using java.reflect

7 files changed, 23 insertions, 39 deletions

diff --git a/core/src/main/scala/mill/define/Module.scala b/core/src/main/scala/mill/define/Module.scala
index c9240fa0..064741c4 100644
--- a/core/src/main/scala/mill/define/Module.scala
+++ b/core/src/main/scala/mill/define/Module.scala
@@ -4,6 +4,7 @@ import ammonite.main.Router.Overrides
 import ammonite.ops.Path
 
 import scala.annotation.implicitNotFound
+import scala.reflect.ClassTag
 
 sealed trait Segment
 object Segment{
@@ -55,6 +56,14 @@ class Module(implicit ctx0: Module.Ctx) extends mill.moduledefs.Cacher{
   implicit def millModuleSegments: Segments = {
     ctx.segments0 ++ Seq(ctx.segment)
   }
+  def reflect[T: ClassTag] = {
+    this
+      .getClass
+      .getMethods
+      .filter(_.getParameterCount == 0)
+      .filter(implicitly[ClassTag[T]].runtimeClass isAssignableFrom _.getReturnType)
+      .map(_.invoke(this).asInstanceOf[T])
+  }
 }
 object Module{
   @implicitNotFound("Modules, Targets and Commands can only be defined within a mill Module")
diff --git a/core/src/main/scala/mill/define/Task.scala b/core/src/main/scala/mill/define/Task.scala
index eac64cd5..2a670d21 100644
--- a/core/src/main/scala/mill/define/Task.scala
+++ b/core/src/main/scala/mill/define/Task.scala
@@ -42,6 +42,7 @@ abstract class Task[+T] extends Task.Ops[T] with Applyable[Task, T]{
 
 trait NamedTask[+T] extends Task[T]{
   def ctx: Module.Ctx
+  def label = ctx.segment match{case Segment.Label(v) => v}
 }
 trait Target[+T] extends NamedTask[T]{
   override def asTarget = Some(this)
diff --git a/core/src/main/scala/mill/discover/Discovered.scala b/core/src/main/scala/mill/discover/Discovered.scala
index 98d4ebb9..6296645a 100644
--- a/core/src/main/scala/mill/discover/Discovered.scala
+++ b/core/src/main/scala/mill/discover/Discovered.scala
@@ -3,7 +3,6 @@ package mill.discover
 import mill.define._
 import ammonite.main.Router
 import ammonite.main.Router.EntryPoint
-import mill.discover.Mirror.TargetPoint
 import mill.util.Ctx.Loader
 import mill.util.Strict.Agg
 
@@ -30,8 +29,7 @@ object Discovered {
 
     val targets = Agg.from(
       Mirror.traverseNode(base, mirror){ (mirror, segmentsRev, resolvedNode) =>
-        for(target <- mirror.targets)
-        yield target.asInstanceOf[TargetPoint[Any, Any]].run(resolvedNode)
+        resolvedNode.asInstanceOf[mill.Module].reflect[Target[_]]
       }
     )
 
@@ -69,24 +67,6 @@ object Discovered {
 
       val r = new Router(c)
 
-      val targets = for {
-        m <- t.members.toList
-        if m.isMethod &&
-           m.typeSignature.paramLists.isEmpty &&
-           m.typeSignature.resultType <:< c.weakTypeOf[Target[_]] &&
-           !m.name.toString.contains(' ') &&
-           m.isPublic
-      } yield {
-        val x = Ident(TermName(c.freshName()))
-        val t = q"""mill.discover.Mirror.TargetPoint(
-          ${m.name.toString},
-          ($x: ${m.typeSignature.resultType}) => $x.${m.name.toTermName}
-        )"""
-
-        c.internal.setPos(t, m.pos)
-        t
-      }
-
       val crossChildren =
         if (!(t <:< c.weakTypeOf[Cross[_]])) q"None"
         else {
@@ -128,7 +108,6 @@ object Discovered {
       q"""mill.discover.Mirror[$baseType, $t](
         $hierarchySelector,
         $commands,
-        $targets,
         $childHierarchies,
         $crossChildren
       )"""
diff --git a/core/src/main/scala/mill/discover/Mirror.scala b/core/src/main/scala/mill/discover/Mirror.scala
index bb6e44ad..ffa86225 100644
--- a/core/src/main/scala/mill/discover/Mirror.scala
+++ b/core/src/main/scala/mill/discover/Mirror.scala
@@ -15,13 +15,11 @@ import scala.language.experimental.macros
   */
 case class Mirror[-T, V](node: (T, List[List[Any]]) => V,
                          commands: Seq[EntryPoint[V]],
-                         targets: Seq[Mirror.TargetPoint[V, _]],
                          children: List[(String, Mirror[T, _])],
                          crossChildren: Option[(V => List[List[Any]], Mirror[T, _])])
 
 object Mirror{
 
-
   def traverseNode[T, V, R](t: T, hierarchy: Mirror[T, V])
                            (f: (Mirror[T, _], => Segments, => Any) => Seq[R]): Seq[R] = {
     traverse(t, hierarchy){ (mirror, segmentsRev) =>
@@ -48,11 +46,4 @@ object Mirror{
     }
     rec(Nil, hierarchy)
   }
-
-
-  /**
-    * Represents metadata about a particular target, before the target is
-    * materialized for a concrete build
-    */
-  case class TargetPoint[T, V](label: String, run: T => Target[V])
 }
diff --git a/core/src/main/scala/mill/main/ReplApplyHandler.scala b/core/src/main/scala/mill/main/ReplApplyHandler.scala
index c239745a..718ca358 100644
--- a/core/src/main/scala/mill/main/ReplApplyHandler.scala
+++ b/core/src/main/scala/mill/main/ReplApplyHandler.scala
@@ -83,10 +83,13 @@ class ReplApplyHandler(pprinter0: pprint.PPrinter, evaluator: Evaluator[_]) exte
             c.argSignatures.map(s => s.name + ": " + s.typeString).mkString(", ") +
             ")()"
         }) ++
-        (if (mirror.targets.isEmpty) Nil
-        else ctx.applyPrefixColor("\nTargets:").toString +: mirror.targets.sortBy(_.label).map(t =>
-          "\n    ." + t.label + "()"
-        ))
+        (if (m.reflect[Target[_]].isEmpty) Nil
+        else {
+          Seq(ctx.applyPrefixColor("\nTargets:").toString) ++
+          m.reflect[Target[_]].sortBy(_.label).map(t =>
+            "\n    ." + t.label + "()"
+          )
+        })
 
       )
     case t: mill.define.Target[_] if evaluator.mapping.targets.contains(t) =>
diff --git a/core/src/main/scala/mill/main/Resolve.scala b/core/src/main/scala/mill/main/Resolve.scala
index 35b07a26..1567f26a 100644
--- a/core/src/main/scala/mill/main/Resolve.scala
+++ b/core/src/main/scala/mill/main/Resolve.scala
@@ -1,6 +1,6 @@
 package mill.main
 
-import mill.define.{Segment, Segments, Task}
+import mill.define.{Segment, Segments, Target, Task}
 import mill.define.Task.TaskModule
 import mill.discover.Mirror
 import ammonite.main.Router
@@ -17,9 +17,10 @@ object Resolve {
       case Segment.Cross(_) :: Nil => Left("Selector cannot start with a [cross] segment")
       case Segment.Label(last) :: Nil =>
         def target =
-          hierarchy.targets
+          hierarchy.node(obj, remainingCrossSelectors).asInstanceOf[mill.Module]
+            .reflect[Target[_]]
             .find(_.label == last)
-            .map(x => Right(x.run(hierarchy.node(obj, remainingCrossSelectors))))
+            .map(Right(_))
 
         def invokeCommand[V](mirror: Mirror[T, V], name: String) = for{
           cmd <- mirror.commands.find(_.name == name)
diff --git a/core/src/main/scala/mill/util/OSet.scala b/core/src/main/scala/mill/util/AggWrapper.scala
index d0f41777..c2994a9a 100644
--- a/core/src/main/scala/mill/util/OSet.scala
+++ b/core/src/main/scala/mill/util/AggWrapper.scala
@@ -35,7 +35,7 @@ sealed class AggWrapper(strictUniqueness: Boolean){
       )
     def apply[V](items: V*) = from(items)
 
-    def from[V](items: TraversableOnce[V]): Agg[V] = {
+    implicit def from[V](items: TraversableOnce[V]): Agg[V] = {
       val set = new Agg.Mutable[V]()
       items.foreach(set.append)
       set