Make .then() return a real Promise

lib/request-base.js

@@ -46,17 +46,23 @@ exports.timeout = function timeout(ms){
 };
 
 /**
- * Faux promise support
+ * Promise support
  *
- * @param {Function} fulfill
+ * @param {Function} resolve
  * @param {Function} reject
  * @return {Request}
  */
 
-exports.then = function then(fulfill, reject) {
-  return this.end(function(err, res) {
-    err ? reject(err) : fulfill(res);
-  });
+exports.then = function then(resolve, reject) {
+  if (!this._fullfilledPromise) {
+    var self = this;
+    this._fullfilledPromise = new Promise(function(innerResolve, innerReject){
+      self.end(function(err, res){
+        if (err) innerReject(err); else innerResolve(res);
+      });
+    });
+  }
+  return this._fullfilledPromise.then(resolve, reject);
 }
 
 /**

test/basic.js

@@ -64,6 +64,36 @@ describe('request', function(){
         done();
       });
     })
+
+    it('is optional with a promise', function() {
+      if ('undefined' === typeof Promise) {
+        return;
+      }
+
+      return request.get(uri + '/login')
+      .then(function(res) {
+          return res.status;
+      })
+      .then()
+      .then(function(status) {
+          assert.equal(200, status, "Real promises pass results through");
+      });
+    });
+
+    it('called only once with a promise', function() {
+      if ('undefined' === typeof Promise) {
+        return;
+      }
+
+      var req = request.get(uri + '/unique');
+
+      return Promise.all([req, req, req])
+      .then(function(results){
+        results.forEach(function(item){
+          assert.equal(item.body, results[0].body, "It should keep returning the same result after being called once");
+        });
+      });
+    });
   })
 
   describe('res.error', function(){
@@ -83,6 +113,20 @@ describe('request', function(){
         done();
       });
     })
+
+    it('with .then() promise', function(){
+      if ('undefined' === typeof Promise) {
+        return;
+      }
+
+      return request
+      .get(uri + '/error')
+      .then(function(){
+        assert.fail();
+      }, function(err){
+        assert.equal(err.message, 'Internal Server Error');
+      });
+    })
   })
 
   describe('res.header', function(){
@@ -312,6 +356,10 @@ describe('request', function(){
 
   describe('.then(fulfill, reject)', function() {
     it('should support successful fulfills with .then(fulfill)', function(done) {
+      if ('undefined' === typeof Promise) {
+        return done();
+      }
+
       request
       .post(uri + '/echo')
       .send({ name: 'tobi' })
@@ -322,6 +370,10 @@ describe('request', function(){
     })
 
     it('should reject an error with .then(null, reject)', function(done) {
+      if ('undefined' === typeof Promise) {
+        return done();
+      }
+
       request
       .get(uri + '/error')
       .then(null, function(err) {

test/support/server.js

@@ -19,6 +19,11 @@ app.all('/echo', function(req, res){
   req.pipe(res);
 });
 
+var uniq = 0;
+app.all('/unique', function(req, res){
+  res.send('never the same ' + (uniq++));
+});
+
 app.use(bodyParser.urlencoded({ extended: true }));
 app.use(bodyParser.json());
 app.use(cookieParser());