Running a single test suite/spec in Jasmine
Every developer knows that writing tests is important. To me, tests are like an evidence that I present to my team (or my future self) that the code I’ve written actually works the way I claim it to be. This sounds nice but it wasn’t until recently that I started writing actual tests.
Something I’ve noticed, even with my little testing experience, is that test suites can grow quite big. It’s not long before you end up with a bunch of test suites each containing a good number of specs. This can make the execution very slow. And while you’re developing, there’s no point of running all tests, when you only work on a single spec file. Then you ask yourself “How can I run only a single test suite/spec?”
I’ve already asked myself this question. And there’s a simple solution:
Running a single test suite
By using fdescribe (think of it as a focused describe), Jasmine will only run that particular test suite.
fdescribe('Awesome feature', function () {
// ... specs here
});
Running a single spec
By using fit (think of it as a focused it), Jasmine will run only that particular spec.
describe('Awesome feature', function () {
fit('should check whether `true` is really `true`', function () {
expect(true).toBe(true);
});
});
So here you go. If you need to run a single test suite/spec, you can quickly do so by using fdescribe and fit.
But beware! When you’re done with your tests, don’t commit the fdescribe/fit because that will give you a false confidence that your tests are successful when in reality it’s only one suite/spec that is being executed.
Update: I built a VS Code extension that will visually highlight tests using fdescribe/fit so you don’t miss them.
