# TOC
   - [#virtual](#virtual)
<a name=""></a>
 
<a name="virtual"></a>
# #virtual
should be a function.

```js
unit.function(virtual);
return null;
```

should do nothing when url has no ext.

```js
unit.httpAgent(app).get('/test').set('Accept', 'text/html').expect(200).expect('Content-Type', /^text\/html/i).expect('X-Request-URL', '/test').end(done);
return null;
```

should replace js ext in url with appropriate accept header.

```js
unit.httpAgent(app).get('/test.js').expect(200).expect('Content-Type', /^application\/javascript/i).expect('X-Request-URL', '/test').end(done);
return null;
```

should replace json ext in url with appropriate accept header.

```js
unit.httpAgent(app).get('/test.json').expect(200).expect('Content-Type', /^application\/json/i).expect('X-Request-URL', '/test').end(done);
return null;
```

should replace xml ext in url with appropriate accept header.

```js
unit.httpAgent(app).get('/test.xml').expect(200).expect('Content-Type', /^application\/xml/i).expect('X-Request-URL', '/test').end(done);
return null;
```

should replace html ext in url with appropriate accept header.

```js
unit.httpAgent(app).get('/test.html').expect(200).expect('Content-Type', /^text\/html/i).expect('X-Request-URL', '/test').end(done);
return null;
```

should replace txt ext in url with appropriate accept header.

```js
unit.httpAgent(app).get('/test.txt').expect(200).expect('Content-Type', /^text\/plain/i).expect('X-Request-URL', '/test').end(done);
return null;
```

should replace jpg ext in url with appropriate accept header.

```js
unit.httpAgent(app).get('/test.jpg').expect(200).expect('Content-Type', /^image\/jpeg/i).expect('X-Request-URL', '/test').end(done);
return null;
```

should replace ext in url and retain query parameters.

```js
unit.httpAgent(app).get('/test.json?q=hi&test=1').expect(200).expect('Content-Type', /^application\/json/i).expect('X-Request-URL', '/test?q=hi&test=1').end(done);
return null;
```