Fixing failing tests

lib/axios.js

@@ -6,6 +6,7 @@ var spread = require('./spread');
 var axios = module.exports = function axios(config) {
   config = utils.merge({
     method: 'get',
+    headers: {},
     transformRequest: defaults.transformRequest,
     transformResponse: defaults.transformResponse
   }, config);

lib/defaults.js

@@ -19,7 +19,7 @@ module.exports = {
     }
     if (utils.isObject(data) && !utils.isFile(data) && !utils.isBlob(data)) {
       // Set application/json if no Content-Type has been specified
-      if (utils.isUndefined(headers['Content-Type'])) {
+      if (!utils.isUndefined(headers) && utils.isUndefined(headers['Content-Type'])) {
         headers['Content-Type'] = 'application/json;charset=utf-8';
       }
       return JSON.stringify(data);

lib/utils.js

@@ -56,6 +56,16 @@ function isNumber(val) {
   return typeof val === 'number';
 }
 
+/**
+ * Determine if a value is undefined
+ *
+ * @param {Object} val The value to test
+ * @returns {boolean} True if the value is undefined, otherwise false
+ */
+function isUndefined(val) {
+  return typeof val === 'undefined';
+}
+
 /**
  * Determine if a value is an Object
  *
@@ -182,6 +192,7 @@ module.exports = {
   isString: isString,
   isNumber: isNumber,
   isObject: isObject,
+  isUndefined: isUndefined,
   isDate: isDate,
   isFile: isFile,
   isBlob: isBlob,