Fixed merge conflicts

lib/defaults/env/FormData.js

@@ -0,0 +1,2 @@
+// eslint-disable-next-line strict
+module.exports = require('form-data');

lib/defaults/index.js

@@ -4,6 +4,7 @@ var utils = require('../utils');
 var normalizeHeaderName = require('../helpers/normalizeHeaderName');
 var AxiosError = require('../core/AxiosError');
 var transitionalDefaults = require('./transitional');
+var toFormData = require('./helpers/toFormData');
 
 var DEFAULT_CONTENT_TYPE = {
   'Content-Type': 'application/x-www-form-urlencoded'
@@ -68,10 +69,20 @@ var defaults = {
       setContentTypeIfUnset(headers, 'application/x-www-form-urlencoded;charset=utf-8');
       return data.toString();
     }
-    if (utils.isObject(data) || (headers && headers['Content-Type'] === 'application/json')) {
+
+    var isObjectPayload = utils.isObject(data);
+    var contentType = headers && headers['Content-Type'];
+
+    var isFileList;
+
+    if ((isFileList = utils.isFileList(data)) || (isObjectPayload && contentType === 'multipart/form-data')) {
+      var _FormData = this.env && this.env.FormData;
+      return toFormData(isFileList ? {'files[]': data} : data, _FormData && new _FormData());
+    } else if (isObjectPayload || contentType === 'application/json') {
       setContentTypeIfUnset(headers, 'application/json');
       return stringifySafely(data);
     }
+
     return data;
   }],
 
@@ -109,6 +120,10 @@ var defaults = {
   maxContentLength: -1,
   maxBodyLength: -1,
 
+  env: {
+    FormData: require('./defaults/env/FormData')
+  },
+
   validateStatus: function validateStatus(status) {
     return status >= 200 && status < 300;
   },