[SPARK-20492][SQL] Do not print empty parentheses for invalid primitive types in parser

## What changes were proposed in this pull request?

Currently, when the type string is invalid, it looks printing empty parentheses. This PR proposes a small improvement in an error message by removing it in the parse as below:

```scala
spark.range(1).select($"col".cast("aa"))
```

**Before**

```
org.apache.spark.sql.catalyst.parser.ParseException:
DataType aa() is not supported.(line 1, pos 0)

== SQL ==
aa
^^^
```

**After**

```
org.apache.spark.sql.catalyst.parser.ParseException:
DataType aa is not supported.(line 1, pos 0)

== SQL ==
aa
^^^
```

## How was this patch tested?

Unit tests in `DataTypeParserSuite`.

Author: hyukjinkwon <gurwls223@gmail.com>

Closes #17784 from HyukjinKwon/SPARK-20492.

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/parser/AstBuilder.scala

@@ -1491,8 +1491,8 @@ class AstBuilder extends SqlBaseBaseVisitor[AnyRef] with Logging {
       case ("decimal", precision :: scale :: Nil) =>
         DecimalType(precision.getText.toInt, scale.getText.toInt)
       case (dt, params) =>
-        throw new ParseException(
-          s"DataType $dt${params.mkString("(", ",", ")")} is not supported.", ctx)
+        val dtStr = if (params.nonEmpty) s"$dt(${params.mkString(",")})" else dt
+        throw new ParseException(s"DataType $dtStr is not supported.", ctx)
     }
   }
 

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/parser/DataTypeParserSuite.scala

@@ -30,7 +30,7 @@ class DataTypeParserSuite extends SparkFunSuite {
     }
   }
 
-  def intercept(sql: String): Unit =
+  def intercept(sql: String): ParseException =
     intercept[ParseException](CatalystSqlParser.parseDataType(sql))
 
   def unsupported(dataTypeString: String): Unit = {
@@ -118,6 +118,11 @@ class DataTypeParserSuite extends SparkFunSuite {
   unsupported("struct<x: int")
   unsupported("struct<x int, y string>")
 
+  test("Do not print empty parentheses for no params") {
+    assert(intercept("unkwon").getMessage.contains("unkwon is not supported"))
+    assert(intercept("unkwon(1,2,3)").getMessage.contains("unkwon(1,2,3) is not supported"))
+  }
+
   // DataType parser accepts certain reserved keywords.
   checkDataType(
     "Struct<TABLE: string, DATE:boolean>",

sql/core/src/test/resources/sql-tests/results/json-functions.sql.out

@@ -141,7 +141,7 @@ struct<>
 -- !query 13 output
 org.apache.spark.sql.AnalysisException
 
-DataType invalidtype() is not supported.(line 1, pos 2)
+DataType invalidtype is not supported.(line 1, pos 2)
 
 == SQL ==
 a InvalidType

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

@@ -274,7 +274,7 @@ class JsonFunctionsSuite extends QueryTest with SharedSQLContext {
     val errMsg2 = intercept[AnalysisException] {
       df3.selectExpr("""from_json(value, 'time InvalidType')""")
     }
-    assert(errMsg2.getMessage.contains("DataType invalidtype() is not supported"))
+    assert(errMsg2.getMessage.contains("DataType invalidtype is not supported"))
     val errMsg3 = intercept[AnalysisException] {
       df3.selectExpr("from_json(value, 'time Timestamp', named_struct('a', 1))")
     }