Merge pull request #3834 from dwijnand/exclusive-cleaning

[sbt 0.13] Fix logging + clean concurrency issue

main/src/main/scala/sbt/Defaults.scala

@@ -343,8 +343,9 @@ object Defaults extends BuildCommon {
 
   lazy val projectTasks: Seq[Setting[_]] = Seq(
     cleanFiles := Seq(managedDirectory.value, target.value),
-    cleanKeepFiles := historyPath.value.toList,
-    clean := doClean(cleanFiles.value, cleanKeepFiles.value),
+    cleanFilesTask := cleanFilesImpl.value,
+    cleanKeepFiles := historyPath.value.toVector,
+    clean := (Def.task { IO.delete(cleanFilesTask.value) } tag (Tags.Clean)).value,
     consoleProject := consoleProjectTask.value,
     watchTransitiveSources := watchTransitiveSourcesTask.value,
     watch := watchSetting.value
@@ -647,10 +648,15 @@ object Defaults extends BuildCommon {
   def detectTests: Initialize[Task[Seq[TestDefinition]]] = (loadedTestFrameworks, compile, streams) map { (frameworkMap, analysis, s) =>
     Tests.discover(frameworkMap.values.toList, analysis, s.log)._1
   }
-  def defaultRestrictions: Initialize[Seq[Tags.Rule]] = parallelExecution { par =>
-    val max = EvaluateTask.SystemProcessors
-    Tags.limitAll(if (par) max else 1) :: Tags.limit(Tags.ForkedTestGroup, 1) :: Nil
-  }
+  def defaultRestrictions: Initialize[Seq[Tags.Rule]] =
+    Def.setting {
+      val par = parallelExecution.value
+      val max = EvaluateTask.SystemProcessors
+      Tags.limitAll(if (par) max else 1) ::
+        Tags.limit(Tags.ForkedTestGroup, 1) ::
+        Tags.exclusiveGroup(Tags.Clean) ::
+        Nil
+    }
 
   lazy val packageBase: Seq[Setting[_]] = Seq(
     artifact := Artifact(moduleName.value)
@@ -775,15 +781,23 @@ object Defaults extends BuildCommon {
     pickMainClass(classes)
   }
 
-  def doClean(clean: Seq[File], preserve: Seq[File]): Unit =
-    IO.withTemporaryDirectory { temp =>
-      val (dirs, files) = preserve.filter(_.exists).flatMap(_.***.get).partition(_.isDirectory)
-      val mappings = files.zipWithIndex map { case (f, i) => (f, new File(temp, i.toHexString)) }
-      IO.move(mappings)
-      IO.delete(clean)
-      IO.createDirectories(dirs) // recreate empty directories
-      IO.move(mappings.map(_.swap))
+  /** Implements `cleanFilesTask` */
+  def cleanFilesImpl: Initialize[Task[Vector[File]]] =
+    Def.task {
+      val filesAndDirs = Vector(managedDirectory.value, target.value)
+      val preserve = cleanKeepFiles.value
+      val (dirs, fs) = filesAndDirs.filter(_.exists).partition(_.isDirectory)
+      val preserveSet = preserve.filter(_.exists).toSet
+      // performance reasons, only the direct items under `filesAndDirs` are allowed to be preserved.
+      val dirItems = dirs flatMap { _.*("*").get }
+      (preserveSet diff dirItems.toSet) match {
+        case xs if xs.isEmpty => ()
+        case xs               => sys.error(s"cleanKeepFiles contains directory/file that are not directly under cleanFiles: $xs")
+      }
+      val toClean = (dirItems filterNot { preserveSet(_) }) ++ fs
+      toClean
     }
+
   def runMainTask(classpath: Initialize[Task[Classpath]], scalaRun: Initialize[Task[ScalaRun]]): Initialize[InputTask[Unit]] =
     {
       import DefaultParsers._

main/src/main/scala/sbt/Keys.scala

@@ -108,7 +108,8 @@ object Keys {
   @deprecated("Use the cacheDirectory provided by streams.", "0.13.0")
   val cacheDirectory = SettingKey[File]("cache-directory", "Directory used for caching task data.", BMinusSetting)
   val cleanFiles = SettingKey[Seq[File]]("clean-files", "The files to recursively delete during a clean.", BSetting)
-  val cleanKeepFiles = SettingKey[Seq[File]]("clean-keep-files", "Files to keep during a clean.", CSetting)
+  val cleanFilesTask = TaskKey[Seq[File]]("clean-files-task", "The files to recursively delete during a clean.", BSetting)
+  val cleanKeepFiles = SettingKey[Seq[File]]("clean-keep-files", "Files or directories to keep during a clean. Must be direct children of target.", CSetting)
   val crossPaths = SettingKey[Boolean]("cross-paths", "If true, enables cross paths, which distinguish input and output directories for cross-building.", ASetting)
   val taskTemporaryDirectory = SettingKey[File]("task-temporary-directory", "Directory used for temporary files for tasks that is deleted after each task execution.", DSetting)
 

main/src/main/scala/sbt/Tags.scala

@@ -13,6 +13,7 @@ object Tags {
   val Test = Tag("test")
   val Update = Tag("update")
   val Publish = Tag("publish")
+  val Clean = Tag("clean")
 
   val CPU = Tag("cpu")
   val Network = Tag("network")
@@ -111,4 +112,4 @@ object Tags {
     val groups = exclusiveTags.count(tag => tags.getOrElse(tag, 0) > 0)
     groups <= 1
   }
-}
+}