settings.js: add some null checks to buildSettingsPage

1 files changed, 8 insertions, 2 deletions

diff --git a/src/librustdoc/html/static/js/settings.js b/src/librustdoc/html/static/js/settings.js
index f61673c9088..ea02e01dccf 100644
--- a/src/librustdoc/html/static/js/settings.js
+++ b/src/librustdoc/html/static/js/settings.js
@@ -289,10 +289,16 @@
         el.innerHTML = innerHTML;
 
         if (isSettingsPage) {
-            document.getElementById(MAIN_ID).appendChild(el);
+            const mainElem = document.getElementById(MAIN_ID);
+            if (mainElem !== null) {
+                mainElem.appendChild(el);
+            }
         } else {
             el.setAttribute("tabindex", "-1");
-            getSettingsButton().appendChild(el);
+            const settingsBtn = getSettingsButton();
+            if (settingsBtn !== null) {
+                settingsBtn.appendChild(el);
+            }
         }
         return el;
     }