[SPARK-24675][SQL]Rename table: validate existence of new location

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/catalog/SessionCatalog.scala

@@ -619,6 +619,7 @@ class SessionCatalog(
         requireTableExists(TableIdentifier(oldTableName, Some(db)))
         requireTableNotExists(TableIdentifier(newTableName, Some(db)))
         validateName(newTableName)
+        validateNewLocationOfRename(oldName, newName)
         externalCatalog.renameTable(db, oldTableName, newTableName)
       } else {
         if (newName.database.isDefined) {
@@ -1366,4 +1367,23 @@ class SessionCatalog(
     // copy over temporary views
     tempViews.foreach(kv => target.tempViews.put(kv._1, kv._2))
   }
+
+  /**
+   * Validate the new locatoin before renaming a managed table, which should be non-existent.
+   */
+  private def validateNewLocationOfRename(
+      oldName: TableIdentifier,
+      newName: TableIdentifier): Unit = {
+    val oldTable = getTableMetadata(oldName)
+    if (oldTable.tableType == CatalogTableType.MANAGED) {
+      val databaseLocation =
+        externalCatalog.getDatabase(oldName.database.getOrElse(currentDb)).locationUri
+      val newTableLocation = new Path(new Path(databaseLocation), formatTableName(newName.table))
+      val fs = newTableLocation.getFileSystem(hadoopConf)
+      if (fs.exists(newTableLocation)) {
+        throw new AnalysisException(s"Can not rename the managed table('$oldName')" +
+          s". The associated location('$newTableLocation') already exists.")
+      }
+    }
+  }
 }

sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala

@@ -441,6 +441,24 @@ abstract class DDLSuite extends QueryTest with SQLTestUtils {
     }
   }
 
+  test("rename a managed table with existing empty directory") {
+    val tableLoc = new File(spark.sessionState.catalog.defaultTablePath(TableIdentifier("tab2")))
+    try {
+      withTable("tab1") {
+        sql(s"CREATE TABLE tab1 USING $dataSource AS SELECT 1, 'a'")
+        tableLoc.mkdir()
+        val ex = intercept[AnalysisException] {
+          sql("ALTER TABLE tab1 RENAME TO tab2")
+        }.getMessage
+        val expectedMsg = "Can not rename the managed table('`tab1`'). The associated location"
+        assert(ex.contains(expectedMsg))
+      }
+    } finally {
+      waitForTasksToFinish()
+      Utils.deleteRecursively(tableLoc)
+    }
+  }
+
   private def checkSchemaInCreatedDataSourceTable(
       path: File,
       userSpecifiedSchema: Option[String],