Added builder for ORDER keyword.

Author: udan11

src/Components/OrderKeyword.php

@@ -37,7 +37,19 @@ class OrderKeyword extends Component
      *
      * @var string
      */
-    public $type = 'ASC';
+    public $type;
+
+    /**
+     * Constructor.
+     *
+     * @param Expression $field The field that we are sorting by.
+     * @param string     $type  The sorting type.
+     */
+    public function __construct($field = null, $type = 'ASC')
+    {
+        $this->field = $field;
+        $this->type = $type;
+    }
 
     /**
      * @param Parser     $parser  The parser that serves as context.
@@ -110,4 +122,22 @@ public static function parse(Parser $parser, TokensList $list, array $options =
         --$list->idx;
         return $ret;
     }
+
+    /**
+     * @param OrderKeyword $component The component to be built.
+     *
+     * @return string
+     */
+    public static function build($component)
+    {
+        if (is_array($component)) {
+            $ret = array();
+            foreach ($component as $c) {
+                $ret[] = static::build($c);
+            }
+            return implode(", ", $ret);
+        } else {
+            return Expression::build($component->field) . ' ' . $component->type;
+        }
+    }
 }

tests/Components/OrderKeywordTest.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace SqlParser\Tests\Components;
+
+use SqlParser\Parser;
+use SqlParser\Components\Expression;
+use SqlParser\Components\OrderKeyword;
+
+use SqlParser\Tests\TestCase;
+
+class OrderKeywordTest extends TestCase
+{
+
+    public function testBuild()
+    {
+        $this->assertEquals(
+            OrderKeyword::build(
+                array(
+                    new OrderKeyword(new Expression('a'), 'ASC'),
+                    new OrderKeyword(new Expression('b'), 'DESC')
+                )
+            ),
+            'a ASC, b DESC'
+        );
+    }
+}