For yarn-cluster and python, do not add primaryResource to spark.jar

These scenarios already distribute the primary resource properly. See
code comments for more detail.

core/src/main/scala/org/apache/spark/deploy/SparkSubmit.scala

@@ -114,13 +114,16 @@ object SparkSubmit {
     val sysProps = new HashMap[String, String]()
     var childMainClass = ""
 
+    val isPython = args.isPython
+    val isYarnCluster = clusterManager == YARN && deployOnCluster
+
     if (clusterManager == MESOS && deployOnCluster) {
       printErrorAndExit("Cannot currently run driver on the cluster in Mesos")
     }
 
     // If we're running a Python app, set the Java class to run to be our PythonRunner, add
     // Python files to deployment list, and pass the main file and Python path to PythonRunner
-    if (args.isPython) {
+    if (isPython) {
       if (deployOnCluster) {
         printErrorAndExit("Cannot currently run Python driver programs on cluster")
       }
@@ -212,11 +215,15 @@ object SparkSubmit {
     }
 
     // Add the application jar automatically so the user doesn't have to call sc.addJar
-    var jars = sysProps.get("spark.jars").map(x => x.split(",").toSeq).getOrElse(Seq())
-    if (args.primaryResource != RESERVED_JAR_NAME) {
-      jars = jars ++ Seq(args.primaryResource)
+    // For YARN cluster mode, the jar is already distributed on each node as "app.jar"
+    // For python files, the primary resource is already distributed as a regular file
+    if (!isYarnCluster && !isPython) {
+      var jars = sysProps.get("spark.jars").map(x => x.split(",").toSeq).getOrElse(Seq())
+      if (args.primaryResource != RESERVED_JAR_NAME) {
+        jars = jars ++ Seq(args.primaryResource)
+      }
+      sysProps.put("spark.jars", jars.mkString(","))
     }
-    sysProps.put("spark.jars", jars.mkString(","))
 
     // Standalone cluster specific configurations
     if (deployOnCluster && clusterManager == STANDALONE) {

core/src/test/scala/org/apache/spark/deploy/SparkSubmitSuite.scala

@@ -99,7 +99,8 @@ class SparkSubmitSuite extends FunSuite with ShouldMatchers {
     val clArgs = Seq(
       "--name", "myApp",
       "--class", "Foo",
-      "userjar.jar", "some",
+      "userjar.jar",
+      "some",
       "--weird", "args")
     val appArgs = new SparkSubmitArguments(clArgs)
     appArgs.childArgs should be (Seq("some", "--weird", "args"))
@@ -138,7 +139,6 @@ class SparkSubmitSuite extends FunSuite with ShouldMatchers {
     mainClass should be ("org.apache.spark.deploy.yarn.Client")
     classpath should have length (0)
     sysProps("spark.app.name") should be ("beauty")
-    sysProps("spark.jars") should be ("thejar.jar")
     sysProps("SPARK_SUBMIT") should be ("true")
   }