From 207a0862045342c104882b6aa5a842c0063bb141 Mon Sep 17 00:00:00 2001
From: Phil Brown <phil.brown@airtasker.com>
Date: Wed, 27 Apr 2022 10:03:29 +1000
Subject: [PATCH] Fixing FormData content-type handling in XHR

Removes the content-type request header if the request body is FormData
and the request is made from a standard browser environment
---
 lib/adapters/xhr.js        |  8 ++++++--
 test/specs/headers.spec.js | 13 +++++++++++++
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/lib/adapters/xhr.js b/lib/adapters/xhr.js
index 5da074dde9..c0822bf796 100644
--- a/lib/adapters/xhr.js
+++ b/lib/adapters/xhr.js
@@ -151,8 +151,12 @@ module.exports = function xhrAdapter(config) {
     // Add headers to the request
     if ('setRequestHeader' in request) {
       utils.forEach(requestHeaders, function setRequestHeader(val, key) {
-        if (typeof requestData === 'undefined' && key.toLowerCase() === 'content-type') {
-          // Remove Content-Type if data is undefined
+        if (
+          key.toLowerCase() === 'content-type' &&
+          (typeof requestData === 'undefined' ||
+            (utils.isFormData(requestData) && utils.isStandardBrowserEnv()))
+        ) {
+          // Remove Content-Type if data is undefined or FormData in a browser environment
           delete requestHeaders[key];
         } else {
           // Otherwise add header to the request
diff --git a/test/specs/headers.spec.js b/test/specs/headers.spec.js
index c1d10d7b89..04f4bbcf37 100644
--- a/test/specs/headers.spec.js
+++ b/test/specs/headers.spec.js
@@ -112,4 +112,17 @@ describe('headers', function () {
       done();
     });
   });
+
+  it('should remove content-type if data is FormData', function (done) {
+    axios.post('/foo', new FormData(), {
+      headers: {
+        'Content-Type': 'multipart/form-data'
+      }
+    });
+
+    getAjaxRequest().then(function (request) {
+      testHeaderValue(request.requestHeaders, 'Content-Type', undefined);
+      done();
+    })
+  })
 });