[SPARK-12982][SQL] Add table name validation in temp table registration

sql/core/src/main/scala/org/apache/spark/sql/SQLContext.scala

@@ -722,7 +722,7 @@ class SQLContext private[sql](
    * only during the lifetime of this instance of SQLContext.
    */
   private[sql] def registerDataFrameAsTable(df: DataFrame, tableName: String): Unit = {
-    catalog.registerTable(TableIdentifier(tableName), df.logicalPlan)
+    catalog.registerTable(sqlParser.parseTableIdentifier(tableName), df.logicalPlan)
   }
 
   /**

sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala

@@ -1291,4 +1291,16 @@ class DataFrameSuite extends QueryTest with SharedSQLContext {
       Seq(1 -> "a").toDF("i", "j").filter($"i".cast(StringType) === "1"),
       Row(1, "a"))
   }
+
+  test("SPARK-12982: Add table name validation in temp table registration") {
+    val df = Seq("foo", "bar").map(Tuple1.apply).toDF("col")
+    // invalid table name test as below
+    intercept[AnalysisException](df.registerTempTable("t~"))
+    // valid table name test as below
+    df.registerTempTable("table1")
+    // another invalid table name test as below
+    intercept[AnalysisException](df.registerTempTable("#$@sum"))
+    // another invalid table name test as below
+    intercept[AnalysisException](df.registerTempTable("table!#"))
+  }
 }