tests: improve res.download tests

Author: dougwilson

test/res.download.js

@@ -1,7 +1,8 @@
 
-var express = require('../')
-  , request = require('supertest')
-  , assert = require('assert');
+var after = require('after');
+var assert = require('assert');
+var express = require('..');
+var request = require('supertest');
 
 describe('res', function(){
   describe('.download(path)', function(){
@@ -38,27 +39,25 @@ describe('res', function(){
 
   describe('.download(path, fn)', function(){
     it('should invoke the callback', function(done){
-      var app = express()
-        , calls = 0;
+      var app = express();
+      var cb = after(2, done);
 
       app.use(function(req, res){
-        res.download('test/fixtures/user.html', done);
+        res.download('test/fixtures/user.html', cb);
       });
 
       request(app)
       .get('/')
       .expect('Content-Type', 'text/html; charset=UTF-8')
       .expect('Content-Disposition', 'attachment; filename="user.html"')
-      .expect(200, function(err){
-        assert.ifError(err)
-      })
+      .expect(200, cb);
     })
   })
 
   describe('.download(path, filename, fn)', function(){
     it('should invoke the callback', function(done){
-      var app = express()
-        , calls = 0;
+      var app = express();
+      var cb = after(2, done);
 
       app.use(function(req, res){
         res.download('test/fixtures/user.html', 'document', done);
@@ -68,48 +67,47 @@ describe('res', function(){
       .get('/')
       .expect('Content-Type', 'text/html; charset=UTF-8')
       .expect('Content-Disposition', 'attachment; filename="document"')
-      .expect(200, function(err){
-        assert.ifError(err)
-      })
+      .expect(200, cb);
     })
   })
 
   describe('on failure', function(){
     it('should invoke the callback', function(done){
-      var app = express()
-        , calls = 0;
+      var app = express();
 
-      app.use(function(req, res){
+      app.use(function (req, res, next) {
         res.download('test/fixtures/foobar.html', function(err){
-          assert(404 == err.status);
-          assert('ENOENT' == err.code);
-          done();
+          if (!err) return next(new Error('expected error'));
+          res.send('got ' + err.status + ' ' + err.code);
         });
       });
 
       request(app)
       .get('/')
-      .end(function(){});
+      .expect(200, 'got 404 ENOENT', done);
     })
 
     it('should remove Content-Disposition', function(done){
       var app = express()
         , calls = 0;
 
-      app.use(function(req, res){
+      app.use(function (req, res, next) {
         res.download('test/fixtures/foobar.html', function(err){
+          if (!err) return next(new Error('expected error'));
           res.end('failed');
         });
       });
 
       request(app)
       .get('/')
-      .expect('failed')
-      .end(function(err, res){
-        if (err) return done(err);
-        res.header.should.not.have.property('content-disposition');
-        done();
-      });
+      .expect(shouldNotHaveHeader('Content-Disposition'))
+      .expect(200, 'failed', done);
     })
   })
 })
+
+function shouldNotHaveHeader(header) {
+  return function (res) {
+    assert.ok(!(header.toLowerCase() in res.headers), 'should not have header ' + header);
+  };
+}