exceptions: implemented error rendering return

src/Exceptions/Handler.php

@@ -54,8 +54,10 @@ class Handler
 
     /**
      * @param Throwable $e
+     * @param bool      $return
+     * @return string
      */
-    public function exceptionHandler($e)
+    public function exceptionHandler($e, $return = false)
     {
         if (!$this->request instanceof Request) {
             $this->request = new Request();
@@ -63,8 +65,19 @@ class Handler
 
         $handler = $this->handler[$this->environment];
         $handler->report($e);
+        ob_start();
         $handler->render($this->request, $e);
+
+        if ($return) {
+            $output = ob_get_contents();
+            ob_end_clean();
+            return $output;
+        }
+
+        http_response_code(500);
+        ob_end_flush();
         $this->die();
+        return '';
     }
 
     /**

src/Exceptions/Handlers/Whoops.php

@@ -34,6 +34,8 @@ class Whoops extends Legacy implements HandlerInterface
         $whoops = $this->app->make(WhoopsRunner::class);
         $handler = $this->getPrettyPageHandler($e);
         $whoops->pushHandler($handler);
+        $whoops->writeToOutput(false);
+        $whoops->allowQuit(false);
 
         if ($request->isXmlHttpRequest()) {
             $handler = $this->getJsonResponseHandler();

tests/Unit/Exceptions/HandlerTest.php

@@ -49,15 +49,19 @@ class HandlerTest extends TestCase
     public function testExceptionHandler()
     {
         $exception = new Exception();
+        $errorMessage = 'Oh noes, an error!';
 
         /** @var HandlerInterface|Mock $handlerMock */
         $handlerMock = $this->getMockForAbstractClass(HandlerInterface::class);
-        $handlerMock->expects($this->once())
+        $handlerMock->expects($this->atLeastOnce())
             ->method('report')
             ->with($exception);
-        $handlerMock->expects($this->once())
+        $handlerMock->expects($this->atLeastOnce())
             ->method('render')
-            ->with($this->isInstanceOf(Request::class), $exception);
+            ->with($this->isInstanceOf(Request::class), $exception)
+            ->willReturnCallback(function () use ($errorMessage) {
+                echo $errorMessage;
+            });
 
         /** @var Handler|Mock $handler */
         $handler = $this->getMockBuilder(Handler::class)
@@ -68,7 +72,11 @@ class HandlerTest extends TestCase
 
         $handler->setHandler(Handler::ENV_PRODUCTION, $handlerMock);
 
+        $this->expectOutputString($errorMessage);
         $handler->exceptionHandler($exception);
+
+        $return = $handler->exceptionHandler($exception, true);
+        $this->assertEquals($errorMessage, $return);
     }
 
     /**

tests/Unit/Exceptions/Handlers/WhoopsTest.php

@@ -72,6 +72,14 @@ class WhoopsTest extends TestCase
                 [$prettyPageHandler],
                 [$jsonResponseHandler]
             );
+        $whoopsRunner
+            ->expects($this->once())
+            ->method('writeToOutput')
+            ->with(false);
+        $whoopsRunner
+            ->expects($this->once())
+            ->method('allowQuit')
+            ->with(false);
         $whoopsRunner
             ->expects($this->once())
             ->method('handleException')