Merge pull request #6146 from eatkins/metabuild

Prepend scala instance jars to sbt classpath

build.sbt

@@ -1362,7 +1362,9 @@ def scriptedTask(launch: Boolean): Def.Initialize[InputTask[Unit]] = Def.inputTa
     scriptedLaunchOpts.value ++ (if (launch) Some(launchJar) else None),
     scalaVersion.value,
     version.value,
-    (scriptedSbtReduxProj / Test / fullClasspathAsJars).value.map(_.data),
+    (scriptedSbtReduxProj / Test / fullClasspathAsJars).value
+      .map(_.data)
+      .filterNot(_.getName.contains("scala-compiler")),
     streams.value.log
   )
 }

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

@@ -2506,14 +2506,15 @@ object Classpaths {
         val isMeta = isMetaBuild.value
         val force = reresolveSbtArtifacts.value
         val app = appConfiguration.value
-        val sbtCp0 = app.provider.mainClasspath.toList
-        val sbtCp = sbtCp0 map { Attributed.blank(_) }
+        def isJansiOrJLine(f: File) = f.getName.contains("jline") || f.getName.contains("jansi")
+        val scalaInstanceJars = app.provider.scalaProvider.jars.filterNot(isJansiOrJLine)
+        val sbtCp = (scalaInstanceJars ++ app.provider.mainClasspath).map(Attributed.blank)
         val mjars = managedJars(
           classpathConfiguration.value,
           classpathTypes.value,
           update.value
         )
-        if (isMeta && !force) mjars ++ sbtCp
+        if (isMeta && !force) (mjars ++ sbtCp).distinct
         else mjars
       },
       exportedProducts := ClasspathImpl.trackedExportedProducts(TrackLevel.TrackAlways).value,

sbt/src/sbt-test/project/plugin-scala-compiler-dependency/project/Plugin.scala

@@ -0,0 +1,3 @@
+import scala.tools.nsc
+
+object Plugin

sbt/src/sbt-test/project/plugin-scala-compiler-dependency/test

@@ -0,0 +1,2 @@
+> show sbtVersion
+# we just want to test that the project loads