Adding support for custom adapters

README.md

@@ -167,14 +167,14 @@ These are the available config options for making requests. Only the `url` is re
   // `url` is the server URL that will be used for the request
   url: '/user',
   
+  // `method` is the request method to be used when making the request
+  method: 'get', // default
+
   // `baseURL` will be prepended to `url` unless `url` is absolute. 
   // It can be convenient to set `baseURL` for an instance of axios to pass relative URLs 
   // to methods of that instance.
   baseURL: 'https://some-domain.com/api/',
 
-  // `method` is the request method to be used when making the request
-  method: 'get', // default
-
   // `transformRequest` allows changes to the request data before it is sent to the server
   // This is only applicable for request methods 'PUT', 'POST', and 'PATCH'
   // The last function in the array must return a string or an ArrayBuffer
@@ -221,6 +221,12 @@ These are the available config options for making requests. Only the `url` is re
   // should be made using credentials
   withCredentials: false, // default
 
+  // `adapter` allows custom handling of requests which makes testing easier.
+  // Call `resolve` or `reject` and supply a valid response (see [response docs](#response-api)).
+  adapter: function (resolve, reject, config) {
+    /* ... */
+  },
+
   // `auth` indicates that HTTP Basic auth should be used, and supplies credentials.
   // This will set an `Authorization` header, overwriting any existing
   // `Authorization` custom headers you have set using `headers`.

lib/core/dispatchRequest.js

@@ -10,12 +10,21 @@
 module.exports = function dispatchRequest(config) {
   return new Promise(function executor(resolve, reject) {
     try {
-      if ((typeof XMLHttpRequest !== 'undefined') || (typeof ActiveXObject !== 'undefined')) {
+      var adapter;
+
+      if (typeof config.adapter === 'function') {
+        // For custom adapter support
+        adapter = config.adapter;
+      } else if (typeof XMLHttpRequest !== 'undefined') {
         // For browsers use XHR adapter
-        require('../adapters/xhr')(resolve, reject, config);
+        adapter = require('../adapters/xhr');
       } else if (typeof process !== 'undefined') {
         // For node use HTTP adapter
-        require('../adapters/http')(resolve, reject, config);
+        adapter = require('../adapters/http');
+      }
+
+      if (typeof adapter === 'function') {
+        adapter(resolve, reject, config);
       }
     } catch (e) {
       reject(e);

test/specs/adapter.spec.js

@@ -0,0 +1,20 @@
+var axios = require('../../index');
+
+describe('adapter', function () {
+  it('should support custom adapter', function (done) {
+    var called = false;
+
+    axios({
+      url: '/foo',
+      adapter: function (resolve, reject, config) {
+        called = true;
+      }
+    });
+
+    setTimeout(function () {
+      expect(called).toBe(true);
+      done();
+    }, 0);
+  });
+});
+