Merge branch 'hotfix/564-test-path-argument' into release-3.0.0

Close #564

Author: weierophinney

test/ApplicationTest.php

@@ -16,6 +16,7 @@
 use Psr\Http\Message\ServerRequestInterface;
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
+use TypeError;
 use Zend\Expressive\Application;
 use Zend\Expressive\MiddlewareFactory;
 use Zend\Expressive\Router\Middleware\PathBasedRoutingMiddleware as RouteMiddleware;
@@ -128,6 +129,17 @@ public function testPipeCanAcceptAPathArgument($middleware)
         $this->assertNull($this->app->pipe('/foo', $middleware));
     }
 
+    public function testPipeNonSlashPathOnNonStringPipeProduceTypeError()
+    {
+        $middleware1 = function ($request, $response) {
+            return $response;
+        };
+        $middleware2 = $this->createMockMiddleware();
+
+        $this->expectException(TypeError::class);
+        $this->app->pipe($middleware1, $middleware2);
+    }
+
     /**
      * @dataProvider validMiddleware
      * @param string|array|callable|MiddlewareInterface $middleware