Resolve empty path to root in liststatus

Author: ayushtkn

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/viewfs/ViewFileSystem.java

@@ -1202,6 +1202,9 @@ public FileStatus[] listStatus(Path f) throws AccessControlException,
           INodeLink<FileSystem> link = (INodeLink<FileSystem>) inode;
           try {
             String linkedPath = link.getTargetFileSystem().getUri().getPath();
+            if("".equals(linkedPath)) {
+              linkedPath = "/";
+            }
             FileStatus status =
                 ((ChRootedFileSystem)link.getTargetFileSystem())
                 .getMyFs().getFileStatus(new Path(linkedPath));

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/fs/viewfs/TestViewFileSystemOverloadSchemeHdfsFileSystemContract.java

@@ -76,9 +76,9 @@ public void setUp() throws Exception {
     URI defaultFSURI =
         URI.create(conf.get(CommonConfigurationKeys.FS_DEFAULT_NAME_KEY));
     ConfigUtil.addLink(conf, defaultFSURI.getAuthority(), "/user",
-        new URI(defaultFSURI.toString() + "/user"));
+        defaultFSURI);
     ConfigUtil.addLink(conf, defaultFSURI.getAuthority(), "/append",
-        new URI(defaultFSURI.toString() + "/append"));
+        defaultFSURI);
     ConfigUtil.addLink(conf, defaultFSURI.getAuthority(),
         "/FileSystemContractBaseTest/",
         new URI(defaultFSURI.toString() + "/FileSystemContractBaseTest/"));