add ut

sql/hive/src/test/scala/org/apache/spark/sql/internal/SharedStateSuite.scala

@@ -0,0 +1,37 @@
+/*
+ * 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.sql.internal
+
+import org.apache.spark.{SparkConf, SparkContext, SparkFunSuite}
+import org.apache.spark.sql.SparkSession
+
+class SharedStateSuite extends SparkFunSuite {
+
+  test("the catalog should be determined at the very first") {
+    val conf = new SparkConf().setMaster("local").setAppName("SharedState Test")
+    val sc = new SparkContext(conf)
+    val ss = SparkSession.builder().enableHiveSupport().getOrCreate()
+    assert(ss.sharedState.externalCatalog.unwrapped.getClass.getName ===
+      "org.apache.spark.sql.hive.HiveExternalCatalog", "The catalog should be hive ")
+    val ss2 = SparkSession.builder().getOrCreate()
+
+    assert(ss2.sharedState.externalCatalog.unwrapped.getClass.getName ===
+      "org.apache.spark.sql.hive.HiveExternalCatalog", "The catalog should shared across sessions")
+  }
+
+}