Automatic testing for web based projects

Question

Recently I've came up with the question is it worth at all to spent development time to generate automatic unit test for web based projects? I mean it seems useless at some point because at some point those projects are oriented on interactions with users/clients, so you cannot anticipate the whole possible set of user action so you be able to check the correctness of content showed. Even regression test can hardly be done.
So I'm very eager to know to know the opinion of other experienced developers.

Answer 1

Selenium have a good web testing framework

http://seleniumhq.org/

Telerik are also in the process of developing one for web app testing.

http://www.telerik.com/products/web-ui-test-studio.aspx

Answer 2

You cannot anticipate the whole possible set of user action so you be able to check the correctness of content showed.

You can't anticipate all the possible data your code is going to be handed, or all the possible race conditions if it's threaded, and yet you still bother unit testing. Why? Because you can narrow it down a hell of a lot. You can anticipate the sorts of pathological things that will happen. You just have to think about it a bit and get some experience.

User interaction is no different. There are certain things users are going to try and do, pathological or not, and you can anticipate them. Users are just inputting particularly imaginative data. You'll find programmers tend to miss the same sorts of conditions over and over again. I keep a checklist. For example: pump Unicode into everything; put the start date after the end date; enter gibberish data; put tags in everything; leave off the trailing newline; try to enter the same data twice; submit a form, go back and submit it again; take a text file, call it foo.jpg and try to upload it as a picture. You can even write a program to flip switches and push buttons at random, a bad monkey, that'll find all sorts of fun bugs.

Its often as simple as sitting someone down who's unfamiliar with the software and watching them use it. Fight the urge to correct them, just watch them flounder. Its very educational. Steve Krug refers to this as "Advanced Common Sense" and has an excellent book called "Don't Make Me Think" which covers cheap, simple user interaction testing. I highly recommend it. It's a very short and eye opening read.

Finally, the client themselves, if their expectations are properly prepared, can be a fantastic test suite. Be sure they understand its a work in progress, that it will have bugs, that they're helping to make their product better, and that it absolutely should not be used for production data, and let them tinker with the pre-release versions of your product. They'll do all sorts of things you never thought of! They'll be the best and most realistic testing you ever had, FOR FREE! Give them a very simple way to report bugs, preferably just a one button box right on the application which automatically submits their environment and history; the feedback box on Hiveminder is an excellent example. Respond to their bugs quickly and politely (even if its just "thanks for the info") and you'll find they'll be delighted you're so responsive to their needs!

Answer 3

Yes, it is. I just ran into an issue this week with a web site I am working on. I just recently switched-out the data access layer and set up unit tests for my controllers and repositories, but not the UI interactions.

I got bit by a pretty obvious bug that would have been easily caught if I had integration tests. Only through integration tests and UI functionality tests do you find issues with the way different tiers of the application interact with one another.