Merge pull request apache#940 from ankurdave/clear-port-properties-after-tests

After unit tests, clear port properties unconditionally

Author: rxin

core/src/test/scala/org/apache/spark/LocalSparkContext.scala

@@ -40,17 +40,17 @@ trait LocalSparkContext extends BeforeAndAfterEach with BeforeAndAfterAll { self
   }
 
   def resetSparkContext() = {
-    if (sc != null) {
-      LocalSparkContext.stop(sc)
-      sc = null
-    }
+    LocalSparkContext.stop(sc)
+    sc = null
   }
 
 }
 
 object LocalSparkContext {
   def stop(sc: SparkContext) {
-    sc.stop()
+    if (sc != null) {
+      sc.stop()
+    }
     // To avoid Akka rebinding to the same port, since it doesn't unbind immediately on shutdown
     System.clearProperty("spark.driver.port")
     System.clearProperty("spark.hostPort")

core/src/test/scala/org/apache/spark/SharedSparkContext.scala

@@ -33,10 +33,8 @@ trait SharedSparkContext extends BeforeAndAfterAll { self: Suite =>
   }
 
   override def afterAll() {
-    if (_sc != null) {
-      LocalSparkContext.stop(_sc)
-      _sc = null
-    }
+    LocalSparkContext.stop(_sc)
+    _sc = null
     super.afterAll()
   }
 }