Merge branch 'master' into yarn-hs-link-2

Conflicts:
	yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala

Author: Marcelo Vanzin

core/src/main/scala/org/apache/spark/SparkConf.scala

@@ -45,7 +45,7 @@ class SparkConf(loadDefaults: Boolean) extends Cloneable with Logging {
   /** Create a SparkConf that loads defaults from system properties and the classpath */
   def this() = this(true)
 
-  private val settings = new HashMap[String, String]()
+  private[spark] val settings = new HashMap[String, String]()
 
   if (loadDefaults) {
     // Load any spark.* system properties
@@ -210,6 +210,12 @@ class SparkConf(loadDefaults: Boolean) extends Cloneable with Logging {
     new SparkConf(false).setAll(settings)
   }
 
+  /**
+   * By using this instead of System.getenv(), environment variables can be mocked
+   * in unit tests.
+   */
+  private[spark] def getenv(name: String): String = System.getenv(name)
+
   /** Checks for illegal or deprecated config settings. Throws an exception for the former. Not
     * idempotent - may mutate this conf object to convert deprecated settings to supported ones. */
   private[spark] def validateSettings() {
@@ -227,7 +233,7 @@ class SparkConf(loadDefaults: Boolean) extends Cloneable with Logging {
     // Validate spark.executor.extraJavaOptions
     settings.get(executorOptsKey).map { javaOpts =>
       if (javaOpts.contains("-Dspark")) {
-        val msg = s"$executorOptsKey is not allowed to set Spark options (was '$javaOpts)'. " +
+        val msg = s"$executorOptsKey is not allowed to set Spark options (was '$javaOpts'). " +
           "Set them directly on a SparkConf or in a properties file when using ./bin/spark-submit."
         throw new Exception(msg)
       }

core/src/main/scala/org/apache/spark/api/python/PythonRDD.scala

@@ -62,7 +62,7 @@ private[spark] class PythonRDD(
     val env = SparkEnv.get
     val localdir = env.blockManager.diskBlockManager.localDirs.map(
       f => f.getPath()).mkString(",")
-    envVars += ("SPARK_LOCAL_DIR" -> localdir) // it's also used in monitor thread
+    envVars += ("SPARK_LOCAL_DIRS" -> localdir) // it's also used in monitor thread
     val worker: Socket = env.createPythonWorker(pythonExec, envVars.toMap)
 
     // Start a thread to feed the process input from our parent's iterator

core/src/main/scala/org/apache/spark/broadcast/BroadcastFactory.scala

@@ -32,8 +32,19 @@ import org.apache.spark.annotation.DeveloperApi
  */
 @DeveloperApi
 trait BroadcastFactory {
+
   def initialize(isDriver: Boolean, conf: SparkConf, securityMgr: SecurityManager): Unit
+
+  /**
+   * Creates a new broadcast variable.
+   *
+   * @param value value to broadcast
+   * @param isLocal whether we are in local mode (single JVM process)
+   * @param id unique id representing this broadcast variable
+   */
   def newBroadcast[T: ClassTag](value: T, isLocal: Boolean, id: Long): Broadcast[T]
+
   def unbroadcast(id: Long, removeFromDriver: Boolean, blocking: Boolean): Unit
+
   def stop(): Unit
 }