add tests to codify deprecated behavior

test/res.clearCookie.js

@@ -32,5 +32,35 @@ describe('res', function(){
       .expect('Set-Cookie', 'sid=; Path=/admin; Expires=Thu, 01 Jan 1970 00:00:00 GMT')
       .expect(200, done)
     })
+
+    it('should set expires when passed', function(done) {
+      var expiresAt = new Date()
+      var app = express();
+
+      app.use(function(req, res){
+        res.clearCookie('sid', { expires: expiresAt }).end();
+      });
+
+      request(app)
+      .get('/')
+      .expect('Set-Cookie', 'sid=; Path=/; Expires=' + expiresAt.toUTCString() )
+      .expect(200, done)
+    })
+
+    it('should set maxAge when passed', function(done) {
+      var maxAgeInMs = 10000
+      var expiresAt = new Date()
+      var expectedExpires = new Date(expiresAt.getTime() + maxAgeInMs)
+      var app = express();
+
+      app.use(function(req, res){
+        res.clearCookie('sid', { expires: expiresAt, maxAge: maxAgeInMs }).end();
+      });
+
+      request(app)
+      .get('/')
+      .expect('Set-Cookie', 'sid=; Max-Age=10; Path=/; Expires=' + expectedExpires.toUTCString())
+      .expect(200, done)
+    })
   })
 })