Allow passing nulls to select functions.

Closes dresende#32

Author: dxg

lib/Select.js

@@ -258,6 +258,9 @@ function SelectQuery(Dialect, opts) {
 
 						if (Array.isArray(sql.from[i].select[j].c)) {
 							str += sql.from[i].select[j].c.map(function (el) {
+								if (!el) {
+									return Dialect.escapeVal(el);
+								}
 								if (typeof el.type == "function") {
 									switch (el.type()) {
 										case "text":

package.json

@@ -6,7 +6,7 @@
 		"sql",
 		"query"
   	],
-	"version": "0.1.18",
+	"version": "0.1.19",
 	"license": "MIT",
 	"repository": {
 		"url": "http://github.com/dresende/node-sql-query"

test/integration/test-select-type.js

@@ -11,6 +11,11 @@ assert.equal(
 	"SELECT MYFUN(`col1`, `col2`) FROM `table1`"
 );
 
+assert.equal(
+  common.Select().from('table1').fun('dbo.fnBalance', [ 80, null, null], 'balance').build(),
+  "SELECT DBO.FNBALANCE(80, NULL, NULL) AS `balance` FROM `table1`"
+);
+
 assert.equal(
 	common.Select().from('table1').fun('myfun', [ 'col1', 'col2'], 'alias').build(),
 	"SELECT MYFUN(`col1`, `col2`) AS `alias` FROM `table1`"