SPARK-23877: Validate metadata-only filters are pushed down.

sql/hive/src/test/scala/org/apache/spark/sql/hive/OptimizeHiveMetadataOnlyQuerySuite.scala

@@ -0,0 +1,42 @@
+/*
+ * 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.hive
+
+import org.scalatest.BeforeAndAfter
+
+import org.apache.spark.metrics.source.HiveCatalogMetrics
+import org.apache.spark.sql.QueryTest
+import org.apache.spark.sql.hive.test.TestHiveSingleton
+import org.apache.spark.sql.test.SQLTestUtils
+
+class OptimizeHiveMetadataOnlyQuerySuite extends QueryTest with TestHiveSingleton
+    with BeforeAndAfter with SQLTestUtils {
+
+  test("SPARK-23877: validate metadata-only query pushes filters to metastore") {
+    withTable("metadata_only") {
+      sql("CREATE TABLE metadata_only (id bigint, data string) PARTITIONED BY (part int)")
+      (0 to 100).foreach(p => sql(s"ALTER TABLE metadata_only ADD PARTITION (part=$p)"))
+
+      // verify the number of matching partitions
+      assert(sql("SELECT DISTINCT part FROM metadata_only WHERE part < 10").collect.size === 10)
+
+      // verify that the partition predicate was pushed down to the metastore
+      assert(HiveCatalogMetrics.METRIC_PARTITIONS_FETCHED.getCount === 10)
+    }
+  }
+}