Support PHPUnit 6

Author: carusogabriel

composer.json

@@ -18,7 +18,7 @@
         }
     },
     "require-dev": {
-        "phpunit/phpunit": "^4.8.35 || ^5.7",
-        "clue/block-react": "^1.1"
+        "clue/block-react": "^1.1",
+        "phpunit/phpunit": "^6.4 || ^5.7 || ^4.8.35"
     }
 }

tests/MiddlewareRunnerTest.php

@@ -13,9 +13,12 @@
 
 final class MiddlewareRunnerTest extends TestCase
 {
+    /**
+     * @expectedException RuntimeException
+     * @expectedExceptionMessage No middleware to run
+     */
     public function testDefaultResponse()
     {
-        $this->setExpectedException('\RuntimeException');
         $request = new ServerRequest('GET', 'https://example.com/');
         $middlewares = array();
         $middlewareStack = new MiddlewareRunner($middlewares);
@@ -90,6 +93,42 @@ public function testProcessStack(array $middlewares, $expectedCallCount)
         }
     }
 
+    public function testNextCanBeRunMoreThanOnceWithoutCorruptingTheMiddlewareStack()
+    {
+        $exception = new \RuntimeException('exception');
+        $retryCalled = 0;
+        $error = null;
+        $retry = function ($request, $next) use (&$error, &$retryCalled) {
+            return $next($request)->then(null, function ($et) use (&$error, $request, $next, &$retryCalled) {
+                $retryCalled++;
+                $error = $et;
+                // the $next failed. discard $error and retry once again:
+                return $next($request);
+            });
+        };
+
+        $response = new Response();
+        $called = 0;
+        $runner = new MiddlewareRunner(array(
+            $retry,
+            function () use (&$called, $response, $exception) {
+                $called++;
+                if ($called === 1) {
+                    throw $exception;
+                }
+
+                return $response;
+            }
+        ));
+
+        $request = new ServerRequest('GET', 'https://example.com/');
+
+        $this->assertSame($response, Block\await($runner($request), Factory::create()));
+        $this->assertSame(1, $retryCalled);
+        $this->assertSame(2, $called);
+        $this->assertSame($exception, $error);
+    }
+
     public function testMultipleRunsInvokeAllMiddlewareInCorrectOrder()
     {
         $requests = array(