running tests on a single component

Author: gajdaw

contributing/code/tests.rst

@@ -63,6 +63,15 @@ command:
 The output should display `OK`. If not, you need to figure out what's going on
 and if the tests are broken because of your modifications.
 
+.. tip::
+
+    If you want to test a single component type it's path after `phpunit`
+    command, e.g.:
+
+    .. code-block:: bash
+
+        $ phpunit src/Symfony/Component/Finder/
+
 .. tip::
 
     Run the test suite before applying your modifications to check that they