[DomCrawler] Added support for slicing nodes

src/Symfony/Component/DomCrawler/Crawler.php

@@ -107,7 +107,7 @@ class Crawler extends \SplObjectStorage
 
         // DOM only for HTML/XML content
         if (!preg_match('/(x|ht)ml/i', $type, $xmlMatches)) {
-            return null;
+            return;
         }
 
         $charset = null;
@@ -294,7 +294,7 @@ class Crawler extends \SplObjectStorage
     /**
      * Returns a node given its position in the node list.
      *
-     * @param integer $position The position
+     * @param int     $position The position
      *
      * @return Crawler A new instance of the Crawler with the selected node, or an empty Crawler if it does not exist.
      *
@@ -339,6 +339,19 @@ class Crawler extends \SplObjectStorage
         return $data;
     }
 
+    /**
+     * Slices the list of nodes by $offset and $length.
+     *
+     * @param int     $offset
+     * @param int     $length
+     *
+     * @return Crawler A Crawler instance with the sliced nodes.
+     */
+    public function slice($offset = 0, $length = -1)
+    {
+        return new static(iterator_to_array(new \LimitIterator($this, $offset, $length)), $this->uri);
+    }
+
     /**
      * Reduces the list of nodes by calling an anonymous function.
      *
@@ -806,7 +819,7 @@ class Crawler extends \SplObjectStorage
     }
 
     /**
-     * @param integer $position
+     * @param int     $position
      *
      * @return \DOMElement|null
      */
@@ -818,7 +831,7 @@ class Crawler extends \SplObjectStorage
             }
         }
 
-        return null;
+        return;
     }
 
     /**

src/Symfony/Component/DomCrawler/Tests/CrawlerTest.php

@@ -309,6 +309,16 @@ EOF
         $this->assertEquals(array('0-One', '1-Two', '2-Three'), $data, '->each() executes an anonymous function on each node of the list');
     }
 
+    public function testSlice()
+    {
+        $crawler = $this->createTestCrawler()->filterXPath('//ul[1]/li');
+        $this->assertNotSame($crawler->slice(), $crawler, '->slice() returns a new instance of a crawler');
+        $this->assertInstanceOf('Symfony\\Component\\DomCrawler\\Crawler', $crawler->slice(), '->slice() returns a new instance of a crawler');
+
+        $this->assertCount(3, $crawler->slice(), '->slice() does not slice the nodes in the list if any param is entered');
+        $this->assertCount(1, $crawler->slice(1, 1), '->slice() slices the nodes in the list');
+    }
+
     public function testReduce()
     {
         $crawler = $this->createTestCrawler()->filterXPath('//ul[1]/li');