Create test for configuration ordering regression.

sbt/src/sbt-test/actions/configuration-delegation/build.sbt

@@ -0,0 +1,17 @@
+lazy val foo = taskKey[Unit]("Runs the foo task")
+
+lazy val bar = taskKey[Unit]("Runs the bar task")
+
+def makeFoo(config: Configuration): Setting[_] = 
+  foo in config := IO.write(file(s"${config.name}-foo"), "foo")
+
+lazy val PerformanceTest = (config("pt") extend Test)
+
+lazy val root = (
+  (project in file("."))
+  .configs(PerformanceTest)
+  .settings(Seq(Compile, Test, Runtime, PerformanceTest).map(makeFoo) :_*)
+  .settings(
+     bar in PerformanceTest := IO.write(file("pt-bar"), "bar")
+  )
+)

sbt/src/sbt-test/actions/configuration-delegation/test

@@ -0,0 +1,8 @@
+# First make sure a task just on the new config delegates.
+> bar
+$ exists pt-bar
+
+
+# Now make sure compile is the default configuration
+> foo
+$ exists compile-foo