Assertion for seeEmailDoesNotContain. Fixes #13

Author: jimmypuckett

src/MailTracking.php

@@ -134,6 +134,22 @@ protected function seeEmailContains($excerpt, Swift_Message $message = null)
         return $this;
     }
 
+    /**
+     * Assert that the last email's body does not contain the given text.
+     *
+     * @param string             $excerpt
+     * @param Swift_Message|null $message
+     *
+     * @return PHPUnit_Framework_TestCase $this
+     */
+    protected function seeEmailDoesNotContain($excerpt, Swift_Message $message = null)
+    {
+        $this->assertNotContains($excerpt, $this->getEmail($message)
+                                                ->getBody(), "Email containing the provided text was found in the body.");
+
+        return $this;
+    }
+
     /**
      * Assert that the last email's body equals the given text.
      *