Add regression and integration test suite

Port the stress-test findings into PHPUnit: realistic brett-parson.com
route model, known-issue baselines, router boundary cases, and a
standalone scaling benchmark (composer bench).

1 files changed, 26 insertions, 0 deletions

diff --git a/tests/Fixtures/StatefulMiddleware.php b/tests/Fixtures/StatefulMiddleware.php
new file mode 100644
index 0000000..d374238
--- /dev/null
+++ b/tests/Fixtures/StatefulMiddleware.php
@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace BrettParson\MiniRoute\Tests\Fixtures;
+
+use BrettParson\MiniRoute\Http\RequestInterface;
+use BrettParson\MiniRoute\Http\ResponseInterface;
+use BrettParson\MiniRoute\Middleware\MiddlewareInterface;
+
+/**
+ * Deliberately stateful middleware. Probes the singleton-container leak:
+ * when a resolver returns the same instance per request, state accumulates
+ * across dispatches (usage contract; ADR work in miniroute-k4i.3).
+ */
+final class StatefulMiddleware implements MiddlewareInterface
+{
+    public int $count = 0;
+
+    public function handle(RequestInterface $request, callable $next): ResponseInterface
+    {
+        $this->count++;
+
+        return $next($request);
+    }
+}