Minor code cleanup

scripted/base/src/main/scala/xsbt/test/TestScriptParser.scala

@@ -30,7 +30,7 @@ private object TestScriptParser {
 
 import TestScriptParser._
 class TestScriptParser(handlers: Map[Char, StatementHandler]) extends RegexParsers {
-  require(!handlers.isEmpty)
+  require(handlers.nonEmpty)
   override def skipWhitespace = false
 
   import IO.read

scripted/sbt/src/main/scala/sbt/test/ScriptedTests.scala

@@ -156,7 +156,7 @@ private[test] final class ListTests(baseDirectory: File, accept: ScriptedTest =>
         val (included, skipped) = allTests.toList.partition(test => accept(ScriptedTest(groupName, test.getName)))
         if (included.isEmpty)
           log.warn("Test group " + groupName + " skipped.")
-        else if (!skipped.isEmpty) {
+        else if (skipped.nonEmpty) {
           log.warn("Tests skipped in group " + group.getName + ":")
           skipped.foreach(testName => log.warn(" " + testName.getName))
         }