Patch 1

components/stopwatch.rst

@@ -52,6 +52,10 @@ while it is still running.
     .. versionadded:: 3.4
         Full precision support was introduced in Symfony 3.4.
 
+The stopwatch can be reset to its original state at any given time with the
+:method:`Symfony\\Component\\Stopwatch\\Stopwatch::reset` method, which deletes
+all the data measured so far.
+
 You can also provide a category name to an event::
 
     $stopwatch->start('eventName', 'categoryName');

debug/debugging.rst

@@ -14,53 +14,6 @@ configuration is optimized for two main purposes:
 * Be as similar as possible as the production environment to avoid problems
   when deploying the project.
 
-Disabling the Bootstrap File and Class Caching
-----------------------------------------------
-
-And to make the production environment as fast as possible, Symfony creates
-big PHP files in your cache containing the aggregation of PHP classes your
-project needs for every request. However, this behavior can confuse your debugger,
-because the same class can be located in two different places: the original class
-file and the big file which aggregates lots of classes.
-
-This recipe shows you how you can tweak this caching mechanism to make it friendlier
-when you need to debug code that involves Symfony classes.
-
-The ``app_dev.php`` front controller reads as follows by default::
-
-    // ...
-
-    $loader = require __DIR__.'/../app/autoload.php';
-    Debug::enable();
-
-    $kernel = new AppKernel('dev', true);
-    $kernel->loadClassCache();
-    $request = Request::createFromGlobals();
-    // ...
-
-To make your debugger happier, disable the loading of all PHP class caches
-by removing the call to ``loadClassCache()``::
-
-    // ...
-
-    $loader = require_once __DIR__.'/../app/autoload.php';
-    Debug::enable();
-
-    $kernel = new AppKernel('dev', true);
-    // $kernel->loadClassCache();
-    $request = Request::createFromGlobals();
-
-.. tip::
-
-    If you disable the PHP caches, don't forget to revert after your debugging
-    session.
-
-Some IDEs do not like the fact that some classes are stored in different
-locations. To avoid problems, you can either tell your IDE to ignore the PHP
-cache files, or you can change the extension used by Symfony for these files::
-
-    $kernel->loadClassCache('classes', '.php.cache');
-
 Useful Debugging Commands
 -------------------------
 

reference/requirements.rst

@@ -6,29 +6,36 @@
 Requirements for Running Symfony
 ================================
 
-Symfony 3.4 requires **PHP 5.5.9** or higher to run, in addition to other minor
+Symfony 4.0 requires **PHP 7.1.3** or higher to run, in addition to other minor
 requirements. To make things simple, Symfony provides a tool to quickly check if
-your system meets all those requirements.
+your system meets all those requirements. Run this command to install the tool:
+
+.. code-block:: terminal
+
+    $ cd your-project/
+    $ composer require requirements-checker
 
 Beware that PHP can define a different configuration for the command console and
 the web server, so you need to check requirements in both environments.
 
 Checking Requirements for the Web Server
 ----------------------------------------
 
-Symfony includes a ``config.php`` file in the ``web/`` directory of your project.
-Open that file with your browser to check the requirements.
+The requirements checker tool creates a file called ``check.php`` in the
+``public/`` directory of your project. Open that file with your browser to check
+the requirements.
 
-Once you've fixed all the reported issues, delete the ``web/config.php`` file
-to avoid leaking internal information about your application to visitors.
+Once you've fixed all the reported issues, uninstall the requirements checker
+to avoid leaking internal information about your application to visitors:
 
-Checking Requirements for the Command Console
----------------------------------------------
+.. code-block:: terminal
 
-Open your console or terminal, enter in your project directory, execute this
-command and fix the reported issues:
+    $ cd your-project/
+    $ composer remove requirements-checker
 
-.. code-block:: terminal
+Checking Requirements for the Command Console
+---------------------------------------------
 
-    $ cd my-project/
-    $ php bin/symfony_requirements
+The requirements checker tool adds a script to your Composer configuration to
+check the requirements automatically. There's no need to execute any command; if
+there is any issue, you'll see them in the console output.