[Console] Add completion to server:dump command

Author: alexandre-daubois

Command/ServerDumpCommand.php

@@ -12,6 +12,8 @@
 namespace Symfony\Component\VarDumper\Command;
 
 use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Completion\CompletionInput;
+use Symfony\Component\Console\Completion\CompletionSuggestions;
 use Symfony\Component\Console\Exception\InvalidArgumentException;
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Input\InputOption;
@@ -55,10 +57,8 @@ public function __construct(DumpServer $server, array $descriptors = [])
 
     protected function configure()
     {
-        $availableFormats = implode(', ', array_keys($this->descriptors));
-
         $this
-            ->addOption('format', null, InputOption::VALUE_REQUIRED, sprintf('The output format (%s)', $availableFormats), 'cli')
+            ->addOption('format', null, InputOption::VALUE_REQUIRED, sprintf('The output format (%s)', implode(', ', $this->getAvailableFormats())), 'cli')
             ->setDescription(self::$defaultDescription)
             ->setHelp(<<<'EOF'
 <info>%command.name%</info> starts a dump server that collects and displays
@@ -99,4 +99,16 @@ protected function execute(InputInterface $input, OutputInterface $output): int
 
         return 0;
     }
+
+    public function complete(CompletionInput $input, CompletionSuggestions $suggestions): void
+    {
+        if ($input->mustSuggestOptionValuesFor('format')) {
+            $suggestions->suggestValues($this->getAvailableFormats());
+        }
+    }
+
+    private function getAvailableFormats(): array
+    {
+        return array_keys($this->descriptors);
+    }
 }

Tests/Command/ServerDumpCommandTest.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace Symfony\Component\VarDumper\Tests\Command;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Console\Tester\CommandCompletionTester;
+use Symfony\Component\VarDumper\Command\ServerDumpCommand;
+use Symfony\Component\VarDumper\Server\DumpServer;
+
+class ServerDumpCommandTest extends TestCase
+{
+    /**
+     * @dataProvider provideCompletionSuggestions
+     */
+    public function testComplete(array $input, array $expectedSuggestions)
+    {
+        $tester = new CommandCompletionTester($this->createCommand());
+
+        $this->assertSame($expectedSuggestions, $tester->complete($input));
+    }
+
+    public function provideCompletionSuggestions()
+    {
+        yield 'option --format' => [
+            ['--format', ''],
+            ['cli', 'html'],
+        ];
+    }
+
+    private function createCommand(): ServerDumpCommand
+    {
+        return new ServerDumpCommand($this->createMock(DumpServer::class));
+    }
+}