From 84a9063c4a5b380c1cc9841958091e7ceae20e31 Mon Sep 17 00:00:00 2001
From: Matthias Schmidt <gravatronics@live.com>
Date: Tue, 5 Jan 2021 18:35:42 +0100
Subject: [PATCH] Properly handle `null` parameters in
 `Upload.appendFormData()`

---
 wcfsetup/install/files/js/WoltLabSuite/Core/Upload.js | 3 +++
 wcfsetup/install/files/ts/WoltLabSuite/Core/Upload.ts | 6 +++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/wcfsetup/install/files/js/WoltLabSuite/Core/Upload.js b/wcfsetup/install/files/js/WoltLabSuite/Core/Upload.js
index 5fb7bdcb35..b97bf49df0 100644
--- a/wcfsetup/install/files/js/WoltLabSuite/Core/Upload.js
+++ b/wcfsetup/install/files/js/WoltLabSuite/Core/Upload.js
@@ -281,6 +281,9 @@ define(["require", "exports", "tslib", "./Ajax/Request", "./Core", "./Dom/Change
             }
             // recursively append additional parameters to form data
             function appendFormData(parameters, prefix) {
+                if (parameters === null) {
+                    return;
+                }
                 prefix = prefix || "";
                 Object.entries(parameters).forEach(([key, value]) => {
                     if (typeof value === "object") {
diff --git a/wcfsetup/install/files/ts/WoltLabSuite/Core/Upload.ts b/wcfsetup/install/files/ts/WoltLabSuite/Core/Upload.ts
index 801f0a9374..c89015a677 100644
--- a/wcfsetup/install/files/ts/WoltLabSuite/Core/Upload.ts
+++ b/wcfsetup/install/files/ts/WoltLabSuite/Core/Upload.ts
@@ -349,7 +349,11 @@ abstract class Upload<TOptions extends UploadOptions = UploadOptions> {
     }
 
     // recursively append additional parameters to form data
-    function appendFormData(parameters: object, prefix?: string): void {
+    function appendFormData(parameters: object | null, prefix?: string): void {
+      if (parameters === null) {
+        return;
+      }
+
       prefix = prefix || "";
 
       Object.entries(parameters).forEach(([key, value]) => {
-- 
2.20.1