1 files changed, 22 insertions, 0 deletions
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
index d8e7cdbd3a..0ab8558c1d 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
@@ -19,13 +19,18 @@ package org.apache.spark.sql
 
 import org.scalatest.BeforeAndAfterAll
 
+import org.apache.spark.sql.catalyst.errors.DialectException
 import org.apache.spark.sql.execution.GeneratedAggregate
 import org.apache.spark.sql.functions._
 import org.apache.spark.sql.TestData._
 import org.apache.spark.sql.test.TestSQLContext
 import org.apache.spark.sql.test.TestSQLContext.{udf => _, _}
+
 import org.apache.spark.sql.types._
 
+/** A SQL Dialect for testing purpose, and it can not be nested type */
+class MyDialect extends DefaultDialect
+
 class SQLQuerySuite extends QueryTest with BeforeAndAfterAll {
   // Make sure the tables are loaded.
   TestData
@@ -74,6 +79,23 @@ class SQLQuerySuite extends QueryTest with BeforeAndAfterAll {
       Row("1", 1) :: Row("2", 1) :: Row("3", 1) :: Nil)
   }
 
+  test("SQL Dialect Switching to a new SQL parser") {
+    val newContext = new SQLContext(TestSQLContext.sparkContext)
+    newContext.setConf("spark.sql.dialect", classOf[MyDialect].getCanonicalName())
+    assert(newContext.getSQLDialect().getClass === classOf[MyDialect])
+    assert(newContext.sql("SELECT 1").collect() === Array(Row(1)))
+  }
+
+  test("SQL Dialect Switch to an invalid parser with alias") {
+    val newContext = new SQLContext(TestSQLContext.sparkContext)
+    newContext.sql("SET spark.sql.dialect=MyTestClass")
+    intercept[DialectException] {
+      newContext.sql("SELECT 1")
+    }
+    // test if the dialect set back to DefaultSQLDialect
+    assert(newContext.getSQLDialect().getClass === classOf[DefaultDialect])
+  }
+
   test("SPARK-4625 support SORT BY in SimpleSQLParser & DSL") {
     checkAnswer(
       sql("SELECT a FROM testData2 SORT BY a"),