Fix remove from Properties + add tests

Because java.util.Properties' remove method takes in an Any
instead of a String, there were some issues with matching the
key's hashCode, so removing was not successful in unit tests.

Instead, this commit fixes it by manually filtering out the keys
and adding them to the child thread's properties.

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

@@ -27,6 +27,7 @@ import java.util.concurrent.atomic.{AtomicReference, AtomicBoolean, AtomicIntege
 import java.util.UUID.randomUUID
 
 import scala.collection.JavaConverters._
+import scala.collection.JavaConversions._
 import scala.collection.{Map, Set}
 import scala.collection.generic.Growable
 import scala.collection.mutable.{HashMap, HashSet}
@@ -349,9 +350,17 @@ class SparkContext(config: SparkConf) extends Logging with ExecutorAllocationCli
   // Thread Local variable that can be used by users to pass information down the stack
   private val localProperties = new InheritableThreadLocal[Properties] {
     override protected def childValue(parent: Properties): Properties = {
-      val p = new Properties(parent)
-      nonInheritedLocalProperties.foreach(p.remove)
-      p
+      if (nonInheritedLocalProperties.nonEmpty) {
+        // If there are properties that should not be inherited, filter them out
+        val p = new Properties
+        val filtered = parent.filter { case (k, _) =>
+          !nonInheritedLocalProperties.contains(k)
+        }
+        p.putAll(filtered)
+        p
+      } else {
+        new Properties(parent)
+      }
     }
     override protected def initialValue(): Properties = new Properties()
   }

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

@@ -154,6 +154,7 @@ class ThreadingSuite extends SparkFunSuite with LocalSparkContext with Logging {
     val threads = (1 to 5).map { i =>
       new Thread() {
         override def run() {
+          // TODO: these assertion failures don't actually fail the test...
           sc.setLocalProperty("test", i.toString)
           assert(sc.getLocalProperty("test") === i.toString)
           sem.release()
@@ -175,6 +176,7 @@ class ThreadingSuite extends SparkFunSuite with LocalSparkContext with Logging {
     val threads = (1 to 5).map { i =>
       new Thread() {
         override def run() {
+          // TODO: these assertion failures don't actually fail the test...
           assert(sc.getLocalProperty("test") === "parent")
           sc.setLocalProperty("test", i.toString)
           assert(sc.getLocalProperty("test") === i.toString)
@@ -190,6 +192,30 @@ class ThreadingSuite extends SparkFunSuite with LocalSparkContext with Logging {
     assert(sc.getLocalProperty("Foo") === null)
   }
 
+  test("inheritance exclusions (SPARK-10548)") {
+    sc = new SparkContext("local", "test")
+    sc.nonInheritedLocalProperties.add("do-not-inherit-me")
+    sc.setLocalProperty("do-inherit-me", "parent")
+    sc.setLocalProperty("do-not-inherit-me", "parent")
+    var throwable: Option[Throwable] = None
+    val threads = (1 to 5).map { i =>
+      new Thread() {
+        override def run() {
+          // only the ones we intend to inherit will be passed to the children
+          try {
+            assert(sc.getLocalProperty("do-inherit-me") === "parent")
+            assert(sc.getLocalProperty("do-not-inherit-me") === null)
+          } catch {
+            case t: Throwable => throwable = Some(t)
+          }
+        }
+      }
+    }
+    threads.foreach(_.start())
+    threads.foreach(_.join())
+    throwable.foreach { t => throw t }
+  }
+
   test("mutations to local properties should not affect submitted jobs (SPARK-6629)") {
     val jobStarted = new Semaphore(0)
     val jobEnded = new Semaphore(0)
@@ -210,6 +236,7 @@ class ThreadingSuite extends SparkFunSuite with LocalSparkContext with Logging {
     // Create a new thread which will inherit the current thread's properties
     val thread = new Thread() {
       override def run(): Unit = {
+        // TODO: these assertion failures don't actually fail the test...
         assert(sc.getLocalProperty(SparkContext.SPARK_JOB_GROUP_ID) === "originalJobGroupId")
         // Sleeps for a total of 10 seconds, but allows cancellation to interrupt the task
         try {

sql/core/src/test/scala/org/apache/spark/sql/execution/SQLExecutionSuite.scala

@@ -0,0 +1,55 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.execution
+
+import org.apache.spark.sql.test.SharedSQLContext
+
+class SQLExecutionSuite extends SharedSQLContext {
+  import testImplicits._
+
+  test("query execution IDs are not inherited across threads") {
+    sparkContext.setLocalProperty(SQLExecution.EXECUTION_ID_KEY, "123")
+    sparkContext.setLocalProperty("do-inherit-me", "some-value")
+    var throwable: Option[Throwable] = None
+    val thread = new Thread {
+      override def run(): Unit = {
+        try {
+          assert(sparkContext.getLocalProperty("do-inherit-me") === "some-value")
+          assert(sparkContext.getLocalProperty(SQLExecution.EXECUTION_ID_KEY) === null)
+        } catch {
+          case t: Throwable =>
+            throwable = Some(t)
+        }
+      }
+    }
+    thread.start()
+    thread.join()
+    throwable.foreach { t => throw t }
+  }
+
+  // This is the end-to-end version of the previous test.
+  test("parallel query execution (SPARK-10548)") {
+    (1 to 5).foreach { i =>
+      // Scala's parallel collections spawns new threads as children of the existing threads.
+      // We need to run this multiple times to ensure new threads are spawned. Without the fix
+      // for SPARK-10548, this usually fails on the second try.
+      val df = sparkContext.parallelize(1 to 5).map { i => (i, i) }.toDF("a", "b")
+      (1 to 10).par.foreach { _ => df.count() }
+    }
+  }
+}