Adding support for complex expressions in the ORDER BY clause (#890)

Author: tomershay

src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt

@@ -2046,7 +2046,7 @@ OrderByElement OrderByElement():
     Expression columnReference = null;
 }
 {
-    columnReference = SimpleExpression()
+    columnReference = Expression()
     [ ( <K_ASC> | (<K_DESC> { orderByElement.setAsc(false); } )) { orderByElement.setAscDescPresent(true); }  ]
     [<K_NULLS> ( 
         <K_FIRST> { orderByElement.setNullOrdering(OrderByElement.NullOrdering.NULLS_FIRST);  }  | 

src/test/java/net/sf/jsqlparser/statement/select/SelectTest.java

@@ -1214,6 +1214,12 @@ public void testOrderByNullsFirst() throws JSQLParserException {
         assertSqlCanBeParsedAndDeparsed(statement);
     }
 
+    @Test
+    public void testOrderByWithComplexExpression() throws JSQLParserException {
+        String statement = "SELECT col FROM tbl tbl_alias ORDER BY tbl_alias.id = 1 DESC";
+        assertSqlCanBeParsedAndDeparsed(statement);
+    }
+
     @Test
     public void testTimestamp() throws JSQLParserException {
         String statement = "SELECT * FROM tab1 WHERE a > {ts '2004-04-30 04:05:34.56'}";