Add happy path test for PlatformInvokeCommand

Add test case that verifies successful command execution with proper platform invocation, result handling, and output display.

Author: OskarStark

src/ai-bundle/tests/Command/PlatformInvokeCommandTest.php

@@ -14,11 +14,46 @@
 use PHPUnit\Framework\TestCase;
 use Symfony\AI\AiBundle\Command\PlatformInvokeCommand;
 use Symfony\AI\AiBundle\Exception\InvalidArgumentException;
+use Symfony\AI\Platform\PlatformInterface;
+use Symfony\AI\Platform\Result\InMemoryRawResult;
+use Symfony\AI\Platform\Result\ResultPromise;
+use Symfony\AI\Platform\Result\TextResult;
+use Symfony\Component\Console\Command\Command;
 use Symfony\Component\Console\Tester\CommandTester;
 use Symfony\Component\DependencyInjection\ServiceLocator;
 
 final class PlatformInvokeCommandTest extends TestCase
 {
+    public function testExecuteSuccessfully()
+    {
+        $textResult = new TextResult('Hello! How can I assist you?');
+        $rawResult = new InMemoryRawResult([]);
+        $promise = new ResultPromise(fn () => $textResult, $rawResult);
+
+        $platform = $this->createMock(PlatformInterface::class);
+        $platform->method('invoke')
+            ->with('gpt-4o-mini', self::anything())
+            ->willReturn($promise);
+
+        $platforms = $this->createMock(ServiceLocator::class);
+        $platforms->method('getProvidedServices')->willReturn(['openai' => 'service_class']);
+        $platforms->method('has')->with('openai')->willReturn(true);
+        $platforms->method('get')->with('openai')->willReturn($platform);
+
+        $command = new PlatformInvokeCommand($platforms);
+        $commandTester = new CommandTester($command);
+
+        $exitCode = $commandTester->execute([
+            'platform' => 'openai',
+            'model' => 'gpt-4o-mini',
+            'message' => 'Hello!',
+        ]);
+
+        self::assertSame(Command::SUCCESS, $exitCode);
+        self::assertStringContainsString('Response:', $commandTester->getDisplay());
+        self::assertStringContainsString('Hello! How can I assist you?', $commandTester->getDisplay());
+    }
+
     public function testExecuteWithNonExistentPlatform()
     {
         $platforms = $this->createMock(ServiceLocator::class);