runBlock

main/src/main/scala/sbt/BackgroundJobService.scala

@@ -110,3 +110,5 @@ abstract class JobHandle {
   def humanReadableName: String
   def spawningTask: ScopedKey[_]
 }
+
+case class RunInfo(handle: JobHandle)

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

@@ -1054,6 +1054,12 @@ object Defaults extends BuildCommon {
       },
       runMain := foregroundRunMainTask.evaluated,
       run := foregroundRunTask.evaluated,
+      runBlock := {
+        val r = run.evaluated
+        val service = bgJobService.value
+        service.waitForTry(r.handle).get
+        r
+      },
       fgRun := runTask(fullClasspath, (run / mainClass), (run / runner)).evaluated,
       fgRunMain := runMainTask(fullClasspath, (run / runner)).evaluated,
       copyResources := copyResourcesTask.value,
@@ -2146,27 +2152,27 @@ object Defaults extends BuildCommon {
     }
 
   // `runMain` calls bgRunMain in the background and pauses the current channel
-  def foregroundRunMainTask: Initialize[InputTask[RunVoid]] =
+  def foregroundRunMainTask: Initialize[InputTask[RunInfo]] =
     Def.inputTask {
       val handle = bgRunMain.evaluated
       val service = bgJobService.value
       val st = state.value
       st.remainingCommands match
         case Nil => service.waitForTry(handle).get
         case _   => service.pauseChannelDuringJob(st, handle)
-      RunVoid
+      RunInfo(handle)
     }
 
   // `run` task calls bgRun in the background and pauses the current channel
-  def foregroundRunTask: Initialize[InputTask[RunVoid]] =
+  def foregroundRunTask: Initialize[InputTask[RunInfo]] =
     Def.inputTask {
       val handle = bgRun.evaluated
       val service = bgJobService.value
       val st = state.value
       st.remainingCommands match
         case Nil => service.waitForTry(handle).get
         case _   => service.pauseChannelDuringJob(st, handle)
-      RunVoid
+      RunInfo(handle)
     }
 
   def runMainTask(

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

@@ -319,8 +319,9 @@ object Keys {
   // Run Keys
   val selectMainClass = taskKey[Option[String]]("Selects the main class to run.").withRank(BMinusTask)
   val mainClass = taskKey[Option[String]]("Defines the main class for packaging or running.").withRank(BPlusTask)
-  val run = inputKey[RunVoid]("Runs a main class, passing along arguments provided on the command line.").withRank(APlusTask)
-  val runMain = inputKey[RunVoid]("Runs the main class selected by the first argument, passing the remaining arguments to the main method.").withRank(ATask)
+  val run = inputKey[RunInfo]("Runs a main class, passing along arguments provided on the command line.").withRank(APlusTask)
+  val runBlock = inputKey[RunInfo]("Runs a main class, and blocks until it's done.").withRank(DTask)
+  val runMain = inputKey[RunInfo]("Runs the main class selected by the first argument, passing the remaining arguments to the main method.").withRank(ATask)
   val discoveredMainClasses = taskKey[Seq[String]]("Auto-detects main classes.").withRank(BMinusTask)
   val runner = taskKey[ScalaRun]("Implementation used to run a main class.").withRank(DTask)
   val trapExit = settingKey[Boolean]("If true, enables exit trapping and thread management for 'run'-like tasks. This was removed in sbt 1.6.0 due to JDK 17 deprecating Security Manager.").withRank(CSetting)

main/src/main/scala/sbt/internal/Aggregation.scala

@@ -80,13 +80,13 @@ object Aggregation {
       case Result.Value(_) => true
       case Result.Inc(_)   => false
     // run task ends earlier than the program run
-    val isRunVoid = results match
-      case Result.Value(Seq(KeyValue(_, RunVoid))) => true
-      case _                                       => false
+    val isRunInfo = results match
+      case Result.Value(Seq(KeyValue(_, RunInfo(_)))) => true
+      case _                                          => false
     results.toEither.foreach { r =>
       if show.taskValues then printSettings(r, show.print) else ()
     }
-    if show.success && !isRunVoid && !state.get(suppressShow).getOrElse(false) then
+    if show.success && !isRunInfo && !state.get(suppressShow).getOrElse(false) then
       printSuccess(start, stop, extracted, success, cacheSummary, log)
     else ()
 

run/src/main/scala/sbt/Run.scala

@@ -212,14 +212,3 @@ object Run:
       case str                      => str
     }).mkString(" ")
 end Run
-
-/**
- * RunVoid is a special `Unit` type used to indicate that it's a `run` task.
- * When a task returns RunVoid, [success] log is omitted.
- */
-sealed trait RunVoid
-
-/**
- * The only resident of RunVoid type.
- */
-case object RunVoid extends RunVoid

sbt-app/src/sbt-test/actions/add-alias/build.sbt

@@ -1,3 +1,3 @@
-addCommandAlias("demo-success", "run true")
-addCommandAlias("demo-failure", "run false")
+addCommandAlias("demo-success", "runBlock true")
+addCommandAlias("demo-failure", "runBlock false")
 addCommandAlias("z", "scalaVersion")

sbt-app/src/sbt-test/classloader-cache/jni/build.sbt

@@ -7,7 +7,7 @@ val dropLibraryPath = taskKey[Unit]("Drop the last path from the java.library.pa
 val wrappedRun = taskKey[Unit]("Run with modified java.library.path")
 val wrappedTest = taskKey[Unit]("Test with modified java.library.path")
 
-def wrap(task: InputKey[Unit]): Def.Initialize[Task[Unit]] =
+def wrap[A1](task: InputKey[A1]): Def.Initialize[Task[Unit]] =
   Def.sequential(appendToLibraryPath, task.toTask(""), dropLibraryPath)
 
 // ThisBuild / turbo := true
@@ -35,6 +35,6 @@ val root = (project in file(".")).settings(
     val cp = System.getProperty("java.library.path", "").split(":").dropRight(1)
     System.setProperty("java.library.path", cp.mkString(":"))
   },
-  wrappedRun := wrap(Runtime / run).value,
+  wrappedRun := wrap(Runtime / runBlock).value,
   wrappedTest := wrap(Test / testOnly).value
 )

sbt-app/src/sbt-test/dependency-management/aar-packaging/test

@@ -1,3 +1,3 @@
 $ delete output
-> run
+> runBlock
 $ exists output

sbt-app/src/sbt-test/dependency-management/exclude-dependencies2/test

@@ -1,3 +1,3 @@
 $ delete output
-> run
+> runBlock
 $ exists output

sbt-app/src/sbt-test/dependency-management/profiles/test

@@ -1,3 +1,3 @@
 $ delete output
-> run
+> runBlock
 $ exists output

sbt-app/src/sbt-test/dependency-management/stdlib-unfreeze/test

@@ -1,12 +1,12 @@
 > a/checkLibs
 > b/checkLibs
 
-> b/run
+> b/runBlock
 $ exists s2.13.8.txt
 $ delete s2.13.8.txt
 
 # don't crash when expanding the macro
-> b3/run
+> b3/runBlock
 $ exists s2.13.10.txt
 $ delete s2.13.10.txt
 

sbt-app/src/sbt-test/dependency-management/url-no-head/test

@@ -1,3 +1,3 @@
 $ delete output
-> run
+> runBlock
 $ exists output

sbt-app/src/sbt-test/package/resources/test

@@ -4,7 +4,7 @@
 
 # This should fail because the Main object is in package jartest and the resource is directly
 # in src/main/resources
--> run
+-> runBlock
 
 > package
 
@@ -18,7 +18,7 @@ $ copy-file src/main/resources/main_resource_test src/main/resources/jartest/mai
 $ delete src/main/resources/main_resource_test
 
 # This should succeed because sbt should put the resource on the runClasspath
-> run
+> runBlock
 
 # This is necessary because package bases whether or not to run on last modified times, which don't have
 # high enough resolution to notice the above move of main_resource_test

sbt-app/src/sbt-test/source-dependencies/constants/test

@@ -3,14 +3,14 @@
 $ copy-file changes/B.scala B.scala
 
 $ copy-file changes/A1.scala A.scala
-> run 1
+> runBlock 1
 $ copy-file changes/A2.scala A.scala
-> run 2
+> runBlock 2
 
 > clean
 > ++2.13.12!
 
 $ copy-file changes/A1.scala A.scala
-> run 1
+> runBlock 1
 $ copy-file changes/A2.scala A.scala
-> run 2
+> runBlock 2

sbt-app/src/sbt-test/source-dependencies/implicit-search/build.sbt

@@ -1,2 +1 @@
-ThisBuild / scalaVersion := "2.12.17"
-
+scalaVersion := "2.12.19"

sbt-app/src/sbt-test/source-dependencies/implicit-search/test

@@ -2,10 +2,10 @@ $ copy-file changes/A1.scala A.scala
 $ copy-file changes/B.scala B.scala
 $ copy-file changes/C.scala C.scala
 > compile
--> run
+-> runBlock
 
 $ copy-file changes/A2.scala A.scala
 $ sleep 1000
 
 > compile
-> run
+> runBlock

sbt-app/src/sbt-test/source-dependencies/java-basic/test

@@ -36,10 +36,10 @@ $ delete src/main/java/a/A.java
 # It shouldn't run though, because it doesn't have a main method
 $ copy-file changes/B1.java src/main/java/a/b/B.java
 > compile
--> run
+-> runBlock
 
 
 # Replace B with a new B that has a main method and should therefore run
 # if the main method was properly detected
 $ copy-file changes/B3.java src/main/java/a/b/B.java
-> run
+> runBlock

sbt-app/src/sbt-test/source-dependencies/linearization/test

@@ -1,7 +1,7 @@
 > compile
 
 # the value of F.x should be 16
-> run 16
+> runBlock 16
 
 # modify D.scala so that the linearization changes
 $ copy-file changes/D.scala D.scala
@@ -12,4 +12,4 @@ $ sleep 1000
 
 # if F is recompiled, the value of x should be 11, otherwise it will still be 16
 # and this will fail
-> run 11
+> runBlock 11

sbt-app/src/sbt-test/source-dependencies/named/test

@@ -4,7 +4,7 @@
 > compile
 
 # result should be 1
-> run 1
+> runBlock 1
 
 # change order of arguments in A.x
 $ copy-file changes/A.scala A.scala
@@ -13,4 +13,4 @@ $ copy-file changes/A.scala A.scala
 > compile
 
 # Should still get 1 and not -1
-> run 1
+> runBlock 1

sbt-app/src/sbt-test/source-dependencies/specialized/test

@@ -2,7 +2,7 @@
 > compile
 
 # verify that erased A.x can be called normally and reflectively
-> run false
+> runBlock false
 
 # make A.x specialized
 $ copy-file changes/A.scala A.scala
@@ -12,4 +12,4 @@ $ copy-file changes/A.scala A.scala
 
 # verify that specialized A.x can be called normally and reflectively
 # NOTE: this test doesn't actually work correctly: have to check the output to see that B.scala was recompiled
-> run true
+> runBlock true