HDFS-13620. Randomize the test directory path for TestHDFSFileSystemContract. Contributed by Anbang Hu.

(cherry picked from commit 27091d2d16c5fea5e5478dd7624d76da173e4fc8)

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestHDFSFileSystemContract.java

@@ -18,6 +18,7 @@
 
 package org.apache.hadoop.hdfs;
 
+import java.io.File;
 import java.io.IOException;
 
 import org.apache.hadoop.conf.Configuration;
@@ -25,6 +26,7 @@ import org.apache.hadoop.fs.CommonConfigurationKeys;
 import org.apache.hadoop.fs.FileSystemContractBaseTest;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.security.UserGroupInformation;
+import org.apache.hadoop.test.GenericTestUtils;
 
 public class TestHDFSFileSystemContract extends FileSystemContractBaseTest {
   
@@ -36,7 +38,9 @@ public class TestHDFSFileSystemContract extends FileSystemContractBaseTest {
     Configuration conf = new HdfsConfiguration();
     conf.set(CommonConfigurationKeys.FS_PERMISSIONS_UMASK_KEY,
         FileSystemContractBaseTest.TEST_UMASK);
-    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
+    File basedir = GenericTestUtils.getRandomizedTestDir();
+    cluster = new MiniDFSCluster.Builder(conf, basedir).numDataNodes(2)
+        .build();
     fs = cluster.getFileSystem();
     defaultWorkingDirectory = "/user/" + 
            UserGroupInformation.getCurrentUser().getShortUserName();