fix(headers): added support for setting header names that overlap with class methods; (#5831)

lib/core/AxiosHeaders.js

@@ -282,7 +282,17 @@ class AxiosHeaders {
 
 AxiosHeaders.accessor(['Content-Type', 'Content-Length', 'Accept', 'Accept-Encoding', 'User-Agent', 'Authorization']);
 
-utils.freezeMethods(AxiosHeaders.prototype);
+// reserved names hotfix
+utils.reduceDescriptors(AxiosHeaders.prototype, ({value}, key) => {
+  let mapped = key[0].toUpperCase() + key.slice(1); // map `set` => `Set`
+  return {
+    get: () => value,
+    set(headerValue) {
+      this[mapped] = headerValue;
+    }
+  }
+});
+
 utils.freezeMethods(AxiosHeaders);
 
 export default AxiosHeaders;

lib/utils.js

@@ -540,8 +540,9 @@ const reduceDescriptors = (obj, reducer) => {
   const reducedDescriptors = {};
 
   forEach(descriptors, (descriptor, name) => {
-    if (reducer(descriptor, name, obj) !== false) {
-      reducedDescriptors[name] = descriptor;
+    let ret;
+    if ((ret = reducer(descriptor, name, obj)) !== false) {
+      reducedDescriptors[name] = ret || descriptor;
     }
   });