Determine error view and message based on type

...not based on status code.

To simplify this logic, we now use the same error "type" both when
routes are not found and specific models are not found. One exception is
ours, one is from Laravel, but for the purposes of error handling they
should be treated the same.

Fixes flarum/core#1641.

framework/core/src/Foundation/ErrorHandling/ViewRenderer.php

@@ -51,26 +51,29 @@ class ViewRenderer implements Formatter
         return new HtmlResponse($view->render(), $error->getStatusCode());
     }
 
+    const ERRORS_WITH_VIEWS = ['csrf_token_mismatch', 'not_found'];
+
     private function determineView(HandledError $error): string
     {
-        $view = [
+        $type = $error->getType();
-            'route_not_found' => '404',
-            'csrf_token_mismatch' => '419',
-        ][$error->getType()] ?? 'default';
 
-        return "flarum.forum::error.$view";
+        if (in_array($type, self::ERRORS_WITH_VIEWS)) {
+            return "flarum.forum::error.$type";
+        } else {
+            return 'flarum.forum::error.default';
+        }
     }
 
     private function getMessage(HandledError $error)
     {
-        return $this->getTranslationIfExists($error->getStatusCode())
+        return $this->getTranslationIfExists($error->getType())
             ?? $this->getTranslationIfExists('unknown')
             ?? 'An error occurred while trying to load this page.';
     }
 
     private function getTranslationIfExists(string $errorType)
     {
-        $key = "core.views.error.${errorType}_message";
+        $key = "core.views.error.$errorType";
         $translation = $this->translator->trans($key, ['{forum}' => $this->settings->get('forum_title')]);
 
         return $translation === $key ? null : $translation;

framework/core/src/Foundation/ErrorServiceProvider.php

@@ -38,8 +38,7 @@ class ErrorServiceProvider extends AbstractServiceProvider
                 'permission_denied' => 403,
 
                 // 404 Not Found
-                'model_not_found' => 404,
+                'not_found' => 404,
-                'route_not_found' => 404,
 
                 // 405 Method Not Allowed
                 'method_not_allowed' => 405,
@@ -52,7 +51,7 @@ class ErrorServiceProvider extends AbstractServiceProvider
         $this->app->singleton('flarum.error.classes', function () {
             return [
                 InvalidParameterException::class => 'invalid_parameter',
-                ModelNotFoundException::class => 'model_not_found',
+                ModelNotFoundException::class => 'not_found',
             ];
         });
 

framework/core/src/Http/Exception/RouteNotFoundException.php

@@ -18,6 +18,6 @@ class RouteNotFoundException extends Exception implements KnownError
 {
     public function getType(): string
     {
-        return 'route_not_found';
+        return 'not_found';
     }
 }

framework/core/views/error/csrf_token_mismatch.blade.php

@@ -6,7 +6,7 @@
   </p>
   <p>
     <a href="javascript:history.back()">
-      {{ $translator->trans('core.views.error.419_return_link') }}
+      {{ $translator->trans('core.views.error.csrf_token_mismatch_return_link') }}
     </a>
   </p>
 @endsection

framework/core/views/error/not_found.blade.php

@@ -6,7 +6,7 @@
   </p>
   <p>
     <a href="{{ $app->url() }}">
-      {{ $translator->trans('core.views.error.404_return_link', ['{forum}' => $settings->get('forum_title')]) }}
+      {{ $translator->trans('core.views.error.not_found_return_link', ['{forum}' => $settings->get('forum_title')]) }}
     </a>
   </p>
 @endsection