[Stopwatch] Add a reset method

Author: jmgq

src/Symfony/Component/Stopwatch/Stopwatch.php

@@ -30,7 +30,7 @@ class Stopwatch
 
     public function __construct()
     {
-        $this->sections = $this->activeSections = array('__root__' => new Section('__root__'));
+        $this->reset();
     }
 
     /**
@@ -156,4 +156,12 @@ public function getSectionEvents($id)
     {
         return isset($this->sections[$id]) ? $this->sections[$id]->getEvents() : array();
     }
+
+    /**
+     * Resets the stopwatch to its original state.
+     */
+    public function reset()
+    {
+        $this->sections = $this->activeSections = array('__root__' => new Section('__root__'));
+    }
 }

src/Symfony/Component/Stopwatch/Tests/StopwatchTest.php

@@ -153,4 +153,16 @@ public function testReopenANewSectionShouldThrowAnException()
         $stopwatch = new Stopwatch();
         $stopwatch->openSection('section');
     }
+
+    public function testReset()
+    {
+        $stopwatch = new Stopwatch();
+
+        $stopwatch->openSection();
+        $stopwatch->start('foo', 'cat');
+
+        $stopwatch->reset();
+
+        $this->assertEquals(new Stopwatch(), $stopwatch);
+    }
 }