1 files changed, 56 insertions, 0 deletions
diff --git a/core/src/test/scala/org/apache/spark/util/CausedBySuite.scala b/core/src/test/scala/org/apache/spark/util/CausedBySuite.scala
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+++ b/core/src/test/scala/org/apache/spark/util/CausedBySuite.scala
@@ -0,0 +1,56 @@
+/*
+ * 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.util
+
+import org.apache.spark.SparkFunSuite
+
+class CausedBySuite extends SparkFunSuite {
+
+  test("For an error without a cause, should return the error") {
+    val error = new Exception
+
+    val causedBy = error match {
+      case CausedBy(e) => e
+    }
+
+    assert(causedBy === error)
+  }
+
+  test("For an error with a cause, should return the cause of the error") {
+    val cause = new Exception
+    val error = new Exception(cause)
+
+    val causedBy = error match {
+      case CausedBy(e) => e
+    }
+
+    assert(causedBy === cause)
+  }
+
+  test("For an error with a cause that itself has a cause, return the root cause") {
+    val causeOfCause = new Exception
+    val cause = new Exception(causeOfCause)
+    val error = new Exception(cause)
+
+    val causedBy = error match {
+      case CausedBy(e) => e
+    }
+
+    assert(causedBy === causeOfCause)
+  }
+}