Add gitlab reporter

src/Container.php

@@ -7,6 +7,7 @@
 use FriendsOfTwig\Twigcs\Reporter\CsvReporter;
 use FriendsOfTwig\Twigcs\Reporter\EmacsReporter;
 use FriendsOfTwig\Twigcs\Reporter\GithubActionReporter;
+use FriendsOfTwig\Twigcs\Reporter\GitlabReporter;
 use FriendsOfTwig\Twigcs\Reporter\JsonReporter;
 use FriendsOfTwig\Twigcs\Reporter\JUnitReporter;
 use FriendsOfTwig\Twigcs\Validator\Validator;
@@ -43,6 +44,10 @@ public function __construct()
             return new GithubActionReporter(new ConsoleReporter());
         };
 
+        $this['reporter.gitlab'] = function () {
+            return new GitlabReporter();
+        };
+
         $this['lexer'] = function () {
             return new Lexer();
         };

src/Reporter/GitlabReporter.php

@@ -0,0 +1,63 @@
+<?php
+declare(strict_types=1);
+
+namespace FriendsOfTwig\Twigcs\Reporter;
+
+use FriendsOfTwig\Twigcs\Validator\Violation;
+use JsonException;
+use Symfony\Component\Console\Output\OutputInterface;
+use function hash;
+use function implode;
+use function json_encode;
+
+class GitlabReporter implements ReporterInterface
+{
+    /**
+     * {@inheritdoc}
+     * @param Violation[] $violations
+     *
+     * @throws JsonException
+     */
+    public function report(OutputInterface $output, array $violations): void
+    {
+        $errors = [];
+
+        foreach ($violations as $violation) {
+            switch($violation->getSeverity()) {
+                case Violation::SEVERITY_INFO:
+                    $severity = 'info';
+                    break;
+                case Violation::SEVERITY_WARNING:
+                    $severity = 'minor';
+                    break;
+                default:
+                    $severity = 'major';
+                    break;
+            }
+
+            $errors[] = [
+                'description' => $violation->getReason(),
+                'fingerprint' => hash(
+                    'sha256',
+                    implode(
+                        [
+                            $violation->getFilename(),
+                            $violation->getLine(),
+                            $violation->getColumn(),
+                            $violation->getReason(),
+                        ]
+                    )
+                ),
+                'severity'    => $severity,
+                'location'    => [
+                    'path'  => $violation->getFilename(),
+                    'lines' => [
+                        'begin' => $violation->getLine(),
+                    ],
+                ],
+            ];
+        }
+
+        $output->writeln(json_encode($errors, JSON_THROW_ON_ERROR | JSON_PRETTY_PRINT));
+    }
+}

tests/Reporter/GitlabReporterTest.php

@@ -0,0 +1,48 @@
+<?php
+declare(strict_types=1);
+
+namespace FriendsOfTwig\Twigcs\Tests\Reporter;
+
+use FriendsOfTwig\Twigcs\Reporter\GitlabReporter;
+use FriendsOfTwig\Twigcs\Validator\Violation;
+use JsonException;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Console\Output\ConsoleOutput;
+
+class GitlabReporterTest extends TestCase
+{
+    public const EXPECTED_REPORT = <<<EOF
+[
+    {
+        "description": "You are not allowed to do that.",
+        "fingerprint": "f72519b40b7ced7c6475d20ae6a0f4d26014891d98a29750dde4931e22745796",
+        "severity": "major",
+        "location": {
+            "path": "template.twig",
+            "lines": {
+                "begin": 10
+            }
+        }
+    }
+]
+EOF;
+
+    /**
+     * @throws JsonException
+     */
+    public function testReport(): void
+    {
+        $reporter = new GitlabReporter();
+        $output = $this->createMock(ConsoleOutput::class);
+
+        $output
+            ->expects($this->once())
+            ->method('writeln')
+            ->with(self::EXPECTED_REPORT)
+        ;
+
+        $reporter->report($output, [
+            new Violation('template.twig', 10, 20, 'You are not allowed to do that.'),
+        ]);
+    }
+}