Merge branch '3.4' into 4.1

* 3.4:
  remove Symfony 2.8 versionadded directive
  Removed a small article about console logging
  Describe things more precisely

Author: javiereguiluz

_build/redirection_map

@@ -119,7 +119,7 @@
 /cookbook/console/commands_as_services /console/commands_as_services
 /cookbook/console/console_command /console
 /cookbook/console/index /console
-/cookbook/console/logging /console/logging
+/cookbook/console/logging /console
 /cookbook/console/request_context /console/request_context
 /cookbook/console/style /console/style
 /cookbook/console/usage /console
@@ -402,3 +402,4 @@
 /components/weblink /components/web_link
 /frontend/encore/installation-no-flex /frontend/encore/installation
 /http_cache/form_csrf_caching /security/csrf
+/console/logging /console

components/console/events.rst

@@ -114,6 +114,8 @@ Listeners receive a
         $event->setError(new \LogicException('Caught exception', $exitCode, $event->getError()));
     });
 
+.. _console-events-terminate:
+
 The ``ConsoleEvents::TERMINATE`` Event
 --------------------------------------
 

console.rst

@@ -37,7 +37,7 @@ want a command to create a user::
     {
         // the name of the command (the part after "bin/console")
         protected static $defaultName = 'app:create-user';
-        
+
         protected function configure()
         {
             // ...
@@ -373,6 +373,15 @@ console::
     :class:`Symfony\\Component\\Console\\Application <Symfony\\Component\\Console\\Application>`
     and extend the normal ``\PHPUnit\Framework\TestCase``.
 
+Logging Command Errors
+----------------------
+
+Whenever an exception is thrown while running commands, Symfony adds a log
+message for it including the entire failing command. In addition, Symfony
+registers an :doc:`event subscriber </event_dispatcher>` to listen to the
+:ref:`ConsoleEvents::TERMINATE event <console-events-terminate>` and adds a log
+message whenever a command doesn't finish with the ``0`` exit status.
+
 Learn More
 ----------
 

service_container/autowiring.rst

@@ -338,9 +338,10 @@ dealing with the ``TransformerInterface``.
 
 .. tip::
 
-    As long as there is only one class implementing the interface and that class
-    is part of the same namespace configuring the alias is not mandatory and Symfony
-    will automatically create one.
+    When using a `service definition prototype`_, if only one service is
+    discovered that implements an interface, and that interface is also
+    discovered at the same time, configuring the alias is not mandatory
+    and Symfony will automatically create one.
 
 Dealing with Multiple Implementations of the Same Type
 ------------------------------------------------------
@@ -500,3 +501,4 @@ Public bundles should explicitly configure their services and not rely on autowi
 
 .. _Rapid Application Development: https://en.wikipedia.org/wiki/Rapid_application_development
 .. _ROT13: https://en.wikipedia.org/wiki/ROT13
+.. _service definition prototype: https://symfony.com/blog/new-in-symfony-3-3-psr-4-based-service-discovery