So I have had this question often, especially from TDDers, on what the best way is to get rapid feedback as you type. One of the biggest things when you do Test Driven Development is the fact that you can see a Red / Green bar or some sort of indicator of your tests. Because that indicator is what tells you what you should be doing. Green bar? Time to write a failing test so you can add that next feature in. Red bar? Well, you know what is broken, so time to go ahead and write that feature. So initially, I used to just hit Alt + Shift + X, T to run the test I was currently editing. And then I learnt the joys of Ctrl + F11, which re runs your last configuration.

But still, I was left wanting more. I mean, I don’t want to have to hit something to tell eclipse to go run my tests. Eclipse already knows when I save, as it can automatically shoot off a build. Why couldn’t I just have another step afterwards which then runs my test, so I don’t have to do anything? It was along this line of thought that I stumbled upon Misko‘s setup of using build steps to run all unit tests at each save. Hallelujah! But the more I used this, the more I started realizing its pain points. You actually had to setup each project to do this? Uh, no. Not happening. Too much effort. I like being lazy.

So then I happened upon this Infinitest thing. The description sounds promising, “A continuous test runner for your JUnit tests.” And what, it “integrates with Eclipse and IntelliJ“. And its “Intelligent and runs only tests that are needed.” I’m sold, where do I sign up? So I went ahead and installed it, and tried it out. And it actually seems to live up to its claim, so far. Its main configuration has a single checkbox, which basically says run Infinitest or don’t run it. Nice. And it integrates seamlessly with the problems view. Like so :

Infinitest results in the problem view

As can be seen above, I made a change which broke two tests. Half a second after I saved those changes, I have problem markers popping up all over my project telling me that the last thing I just did blew up some tests. I can double click on the markers, go to the exact line where the failure is, and see if it was an issue of the test being wrong or me being stupid. And in some cases, that isn’t even needed, because you know the tests shouldn’t have broken.

Infinitest seems to be smart enough to recognize all JUnit tests without you having to point it out, and runs only the tests that matter, and not all of it. But if you have other kinds of tests, then you might run into trouble. I am still playing around with it, and will probably update this post or add a new post later with more detailed info if I deem it necessary. But in the meantime, for those of you who want to run tests at every save, check out Infinitest. It is awesome!