“You should spend at least half of your time in the ‘test’ directory.” — Jeremy Voorhis

“Quit looking at your web browser!” — Eric Hodel

Web development without a browser?

My development process has recently been supercharged by autotest, a part of the ZenTest package that you can download from RubyForge or install as a gem:

sudo gem install ZenTest

See a Movie of autotest in action

Autotest runs continuously and watches to see what files you have edited. Any time you save a file, it will run the corresponding test within a few seconds. If a test fails, you can see the result immediately. If it passes, you can write another test, then the code necessary to make it pass, ad nauseam.

# Run this inside your Rails app's directory
topfunky$ autotest -rails

The revolutionary part of this is that it speeds development by helping you develop without needing to open your web browser! I find myself thinking more about the functional issues that need to be solved rather than the placement of an image or the color of a link.

And since it’s running continuously, you don’t have to wait for your tests to run…they are running almost all the time. When they do run, they often take less time since autotest intelligently diffs the change and runs the test for a single method, when possible.

It makes it hard NOT to do test-driven development. You see the screen sitting there like a hungry fire waiting for another test. Like a fire, it also has an infinite hunger, so you will never beat it.

But the point is…by writing tests you can

• Ensure that changes to your app won’t break other functionality
• Keep yourself on track by focusing your mind on problems, solutions, and the most functional design
• Speed your development by breaking out of the write-refresh-wait-wait-wait-debug cycle