[Console] Updated section 'Building a single Command Application' with the new 'SingleCommandApplication'

Author: lyrixx

components/console/single_command_tool.rst

@@ -8,31 +8,31 @@ When building a command line tool, you may not need to provide several commands.
 In such case, having to pass the command name each time is tedious. Fortunately,
 it is possible to remove this need by declaring a single command application::
 
+.. versionadded:: 5.0
+
+    The class :class:`Symfony\\Component\\Console\\SingleCommandApplication` was
+    introduced in Symfony 5.1.
+
     #!/usr/bin/env php
     <?php
     require __DIR__.'/vendor/autoload.php';
 
-    use Symfony\Component\Console\Application;
     use Symfony\Component\Console\Input\InputArgument;
     use Symfony\Component\Console\Input\InputInterface;
     use Symfony\Component\Console\Input\InputOption;
     use Symfony\Component\Console\Output\OutputInterface;
-
-    (new Application('echo', '1.0.0'))
-        ->register('echo')
-            ->addArgument('foo', InputArgument::OPTIONAL, 'The directory')
-            ->addOption('bar', null, InputOption::VALUE_REQUIRED)
-            ->setCode(function(InputInterface $input, OutputInterface $output) {
-                // output arguments and options
-            })
-        ->getApplication()
-        ->setDefaultCommand('echo', true) // Single command application
+    use Symfony\Component\Console\SingleCommandApplication;
+
+    (new SingleCommandApplication())
+        ->setName('My Super Command') // Optional
+        ->setVersion('1.0.0') // Optional
+        ->addArgument('foo', InputArgument::OPTIONAL, 'The directory')
+        ->addOption('bar', null, InputOption::VALUE_REQUIRED)
+        ->setCode(function(InputInterface $input, OutputInterface $output) {
+            // output arguments and options
+        })
         ->run();
 
-The method :method:`Symfony\\Component\\Console\\Application::setDefaultCommand`
-accepts a boolean as second parameter. If true, the command ``echo`` will then
-always be used, without having to pass its name.
-
 You can still register a command as usual::
 
     #!/usr/bin/env php
@@ -49,3 +49,7 @@ You can still register a command as usual::
 
     $application->setDefaultCommand($command->getName(), true);
     $application->run();
+
+The method :method:`Symfony\\Component\\Console\\Application::setDefaultCommand`
+accepts a boolean as second parameter. If true, the command ``echo`` will then
+always be used, without having to pass its name.