Do not crash when viewing an internal error for a deleted judgehost.

Fixes #1809.

(cherry picked from commit 7060197)

Author: nickygerritsen

webapp/src/Controller/Jury/InternalErrorController.php

@@ -117,8 +117,12 @@ public function viewAction(int $errorId): Response
             case 'judgehost':
                 // Judgehosts get disabled by their hostname, so we need to look it up here.
                 $judgehost    = $this->em->getRepository(Judgehost::class)->findOneBy(['hostname' => $disabled['hostname']]);
-                $affectedLink = $this->generateUrl('jury_judgehost', ['judgehostid' => $judgehost->getJudgehostid()]);
                 $affectedText = $disabled['hostname'];
+                if ($judgehost) {
+                    $affectedLink = $this->generateUrl('jury_judgehost', ['judgehostid' => $judgehost->getJudgehostid()]);
+                } else {
+                    $affectedText .= ' (deleted)';
+                }
                 break;
             case 'language':
                 $affectedLink = $this->generateUrl('jury_language', ['langId' => $disabled['langid']]);

webapp/templates/jury/internal_error.html.twig

@@ -72,7 +72,13 @@
                 {% if affectedText is not null %}
                     <tr>
                         <th>Affected {{ internalError.disabled.kind }}</th>
-                        <td><a href="{{ affectedLink }}">{{ affectedText }}</a></td>
+                        <td>
+                            {% if affectedLink %}
+                                <a href="{{ affectedLink }}">{{ affectedText }}</a>
+                            {% else %}
+                                {{ affectedText }}
+                            {% endif %}
+                        </td>
                     </tr>
                 {% endif %}
                 <tr>