sbt/tasks/src/test/scala/DemoTask.scala

163 lines
7.0 KiB
Scala

/* sbt -- Simple Build Tool
* Copyright 2010 Mark Harrah
*/
package sbt
import Types._
import Task._
import Execute._
sealed trait Task[+T]
sealed case class Pure[+T](eval: () => T) extends Task[T]
final case class Mapped[+T, In <: HList](in: Tasks[In], f: Results[In] => T) extends Task[T]
final case class MapAll[+T, In <: HList](in: Tasks[In], f: In => T) extends Task[T]
final case class FlatMapAll[+T, In <: HList](in: Tasks[In], f: In => Task[T]) extends Task[T]
final case class MapFailure[+T, In <: HList](in: Tasks[In], f: Seq[Incomplete] => T) extends Task[T]
final case class FlatMapFailure[+T, In <: HList](in: Tasks[In], f: Seq[Incomplete] => Task[T]) extends Task[T]
final case class FlatMapped[+T, In <: HList](in: Tasks[In], f: Results[In] => Task[T]) extends Task[T]
final case class DependsOn[+T](in: Task[T], deps: Seq[Task[_]]) extends Task[T]
final case class Join[+T, U](in: Seq[Task[U]], f: Seq[U] => Either[Task[T], T]) extends Task[T] { type Uniform = U }
trait MultiInTask[In <: HList]
{
def flatMap[T](f: In => Task[T]): Task[T]
def flatMapR[T](f: Results[In] => Task[T]): Task[T]
def mapH[T](f: In => T): Task[T]
def mapR[T](f: Results[In] => T): Task[T]
def flatFailure[T](f: Seq[Incomplete] => Task[T]): Task[T]
def mapFailure[T](f: Seq[Incomplete] => T): Task[T]
}
trait SingleInTask[S]
{
def flatMapR[T](f: Result[S] => Task[T]): Task[T]
def flatMap[T](f: S => Task[T]): Task[T]
def map[T](f: S => T): Task[T]
def mapR[T](f: Result[S] => T): Task[T]
def flatFailure[T](f: Incomplete => Task[T]): Task[T]
def mapFailure[T](f: Incomplete => T): Task[T]
def dependsOn(tasks: Task[_]*): Task[S]
}
trait ForkTask[S, CC[_]]
{
def fork[T](f: S => T): CC[Task[T]]
}
trait JoinTask[S, CC[_]]
{
def join: Task[CC[S]]
def reduced(f: (S,S) => S): Task[S]
}
object Task
{
type Tasks[HL <: HList] = KList[Task, HL]
type Results[HL <: HList] = KList[Result, HL]
def pure[T](f: => T): Task[T] = toPure(f _)
def pure[T](name: String, f: => T): Task[T] = new Pure(f _) { override def toString = name }
implicit def toPure[T](f: () => T): Task[T] = new Pure(f)
implicit def pureTasks[S](in: Seq[S]): Seq[Task[S]] = in.map(s => pure(s))
implicit def toTasks[S](in: Seq[() => S]): Seq[Task[S]] = in.map(toPure)
implicit def iterableTask[S](in: Seq[S]): ForkTask[S, Seq] = new ForkTask[S, Seq] {
def fork[T](f: S => T): Seq[Task[T]] = in.map(x => pure(x) map f)
}
implicit def pureJoin[S](in: Seq[S]): JoinTask[S, Seq] = joinTasks(pureTasks(in))
implicit def joinTasks[S](in: Seq[Task[S]]): JoinTask[S, Seq] = new JoinTask[S, Seq] {
def join: Task[Seq[S]] = new Join(in, (s: Seq[S]) => Right(s) )
//def join[T](f: Iterable[S] => T): Task[Iterable[T]] = new MapAll( MList.fromTCList[Task](in), ml => f(ml.toList))
//def joinR[T](f: Iterable[Result[S]] => T): Task[Iterable[Result[T]]] = new Mapped( MList.fromTCList[Task](in), ml => f(ml.toList))
def reduced(f: (S,S) => S): Task[S] = Task.reduced(in.toIndexedSeq, f)
}
implicit def multInputTask[In <: HList](tasks: Tasks[In]): MultiInTask[In] = new MultiInTask[In] {
def flatMap[T](f: In => Task[T]): Task[T] = new FlatMapAll(tasks, f)
def flatMapR[T](f: Results[In] => Task[T]): Task[T] = new FlatMapped(tasks, f)
def mapH[T](f: In => T): Task[T] = new MapAll(tasks, f)
def mapR[T](f: Results[In] => T): Task[T] = new Mapped(tasks, f)
def flatFailure[T](f: Seq[Incomplete] => Task[T]): Task[T] = new FlatMapFailure(tasks, f)
def mapFailure[T](f: Seq[Incomplete] => T): Task[T] = new MapFailure(tasks, f)
}
implicit def singleInputTask[S](in: Task[S]): SingleInTask[S] = new SingleInTask[S] {
type HL = S :+: HNil
private val ml = in :^: KNil
private def headM = (_: Results[HL]).combine.head
private def headH = (_: HL).head
private def headS = (_: Seq[Incomplete]).head
def flatMapR[T](f: Result[S] => Task[T]): Task[T] = new FlatMapped[T, HL](ml, f headM)
def flatMap[T](f: S => Task[T]): Task[T] = new FlatMapAll(ml, f headH)
def map[T](f: S => T): Task[T] = new MapAll(ml, f headH)
def mapR[T](f: Result[S] => T): Task[T] = new Mapped[T, HL](ml, f headM)
def flatFailure[T](f: Incomplete => Task[T]): Task[T] = new FlatMapFailure(ml, f headS)
def mapFailure[T](f: Incomplete => T): Task[T] = new MapFailure(ml, f headS)
def dependsOn(tasks: Task[_]*): Task[S] = new DependsOn(in, tasks)
}
implicit val taskToNode = new (Task ~> NodeT[Task]#Apply) {
def apply[T](t: Task[T]): Node[Task, T] = t match {
case Pure(eval) => toNode[T, HNil](KNil, _ => Right(eval()) )
case Mapped(in, f) => toNode(in, right f )
case MapAll(in, f) => toNode[T, in.Raw](in, right (f compose allM) )
case MapFailure(in, f) => toNode[T, in.Raw](in, right (f compose failuresM))
case FlatMapped(in, f) => toNode(in, left f )
case FlatMapAll(in, f) => toNode[T, in.Raw](in, left (f compose allM) )
case FlatMapFailure(in, f) => toNode[T, in.Raw](in, left (f compose failuresM))
case DependsOn(in, tasks) => join[T, Any](tasks, (_: Seq[Result[_]]) => Left(in))
case j@ Join(in, f) => join[T, j.Uniform](in, f compose all)
}
}
def join[T, D](tasks: Seq[Task[D]], f: Seq[Result[D]] => Either[Task[T], T]): Node[Task, T] = new Node[Task, T] {
type Mixed = HNil
val mixedIn = KNil
type Uniform = D
val uniformIn = tasks
def work(mixed: Results[HNil], uniform: Seq[Result[Uniform]]) = {
val inc = failures(uniform)
if(inc.isEmpty) f(uniform) else throw Incomplete(None, causes = inc)
}
}
def toNode[T, In <: HList](in: Tasks[In], f: Results[In] => Either[Task[T], T]): Node[Task, T] = new Node[Task, T] {
type Mixed = In
val mixedIn = in
type Uniform = Nothing
val uniformIn = Nil
def work(results: Results[In], units: Seq[Result[Uniform]]) = f(results)
}
def allM[In <: HList]: Results[In] => In = in =>
{
val incs = failuresM(in)
if(incs.isEmpty) in.down(Result.tryValue) else throw Incomplete(None, causes = incs)
}
def all[D]: Seq[Result[D]] => Seq[D] = in =>
{
val incs = failures(in)
if(incs.isEmpty) in.map(Result.tryValue.apply[D]) else throw Incomplete(None, causes = incs)
}
def failuresM[In <: HList]: Results[In] => Seq[Incomplete] = x => failures[Any](x.toList)
def failures[A]: Seq[Result[A]] => Seq[Incomplete] = _.collect { case Inc(i) => i }
def run[T](root: Task[T], checkCycles: Boolean, maxWorkers: Int): Result[T] =
{
val (service, shutdown) = CompletionService[Task[_], Completed](maxWorkers)
val x = new Execute[Task](checkCycles, Execute.noTriggers)(taskToNode)
try { x.run(root)(service) } finally { shutdown() }
}
def tryRun[T](root: Task[T], checkCycles: Boolean, maxWorkers: Int): T =
run(root, checkCycles, maxWorkers) match {
case Value(v) => v
case Inc(i) => throw i
}
def reduced[S](i: IndexedSeq[Task[S]], f: (S, S) => S): Task[S] =
i match
{
case Seq() => error("Cannot reduce empty sequence")
case Seq(x) => x
case Seq(x, y) => reducePair(x, y, f)
case z =>
val (a, b) = i.splitAt(i.size / 2)
reducePair( reduced(a, f), reduced(b, f), f )
}
def reducePair[S](a: Task[S], b: Task[S], f: (S, S) => S): Task[S] =
(a :^: b :^: KNil) mapH { case x :+: y :+: HNil => f(x,y) }
}