Closure cleaner unit test

core/src/test/scala/spark/ClosureCleanerSuite.scala

+package spark
+
+import java.io.NotSerializableException
+
+import org.scalatest.FunSuite
+import SparkContext._
+
+class ClosureCleanerSuite extends FunSuite {
+  test("closures inside an object") {
+    assert(TestObject.run() === 30) // 6 + 7 + 8 + 9
+  }
+
+  test("closures inside a class") {
+    val obj = new TestClass
+    assert(obj.run() === 30) // 6 + 7 + 8 + 9
+  }
+
+  test("closures inside a class with no default constructor") {
+    val obj = new TestClassWithoutDefaultConstructor(5)
+    assert(obj.run() === 30) // 6 + 7 + 8 + 9
+  }
+
+  test("closures that don't use fields of the outer class") {
+    val obj = new TestClassWithoutFieldAccess
+    assert(obj.run() === 30) // 6 + 7 + 8 + 9
+  }
+
+  test("nested closures inside an object") {
+    assert(TestObjectWithNesting.run() === 96) // 4 * (1+2+3+4) + 4 * (1+2+3+4) + 16 * 1
+  }
+
+  test("nested closures inside a class") {
+    val obj = new TestClassWithNesting(1)
+    assert(obj.run() === 96) // 4 * (1+2+3+4) + 4 * (1+2+3+4) + 16 * 1
+  }
+}
+
+// A non-serializable class we create in closures to make sure that we aren't
+// keeping references to unneeded variables from our outer closures.
+class NonSerializable {}
+
+object TestObject {
+  def run(): Int = {
+    var nonSer = new NonSerializable
+    var x = 5
+    val sc = new SparkContext("local", "test")
+    val nums = sc.parallelize(Array(1, 2, 3, 4))
+    val answer = nums.map(_ + x).reduce(_ + _)
+    sc.stop()
+    return answer
+  }
+}
+
+class TestClass extends Serializable {
+  var x = 5
+  
+  def getX = x
+
+  def run(): Int = {
+    var nonSer = new NonSerializable
+    val sc = new SparkContext("local", "test")
+    val nums = sc.parallelize(Array(1, 2, 3, 4))
+    val answer = nums.map(_ + getX).reduce(_ + _)
+    sc.stop()
+    return answer
+  }
+}
+
+class TestClassWithoutDefaultConstructor(x: Int) extends Serializable {
+  def getX = x
+
+  def run(): Int = {
+    var nonSer = new NonSerializable
+    val sc = new SparkContext("local", "test")
+    val nums = sc.parallelize(Array(1, 2, 3, 4))
+    val answer = nums.map(_ + getX).reduce(_ + _)
+    sc.stop()
+    return answer
+  }
+}
+
+// This class is not serializable, but we aren't using any of its fields in our
+// closures, so they won't have a $outer pointing to it and should still work.
+class TestClassWithoutFieldAccess {
+  var nonSer = new NonSerializable
+
+  def run(): Int = {
+    var nonSer2 = new NonSerializable
+    var x = 5
+    val sc = new SparkContext("local", "test")
+    val nums = sc.parallelize(Array(1, 2, 3, 4))
+    val answer = nums.map(_ + x).reduce(_ + _)
+    sc.stop()
+    return answer
+  }
+}
+
+
+object TestObjectWithNesting {
+  def run(): Int = {
+    var nonSer = new NonSerializable
+    var answer = 0
+    val sc = new SparkContext("local", "test")
+    val nums = sc.parallelize(Array(1, 2, 3, 4))
+    var y = 1
+    for (i <- 1 to 4) {
+      var nonSer2 = new NonSerializable
+      var x = i
+      answer += nums.map(_ + x + y).reduce(_ + _)
+    }
+    sc.stop()
+    return answer
+  }
+}
+
+class TestClassWithNesting(val y: Int) extends Serializable {
+  def getY = y
+
+  def run(): Int = {
+    var nonSer = new NonSerializable
+    var answer = 0
+    val sc = new SparkContext("local", "test")
+    val nums = sc.parallelize(Array(1, 2, 3, 4))
+    for (i <- 1 to 4) {
+      var nonSer2 = new NonSerializable
+      var x = i
+      answer += nums.map(_ + x + getY).reduce(_ + _)
+    }
+    sc.stop()
+    return answer
+  }
+}