Karma not watching preprocessed files? about karma-rollup-preprocessor HOT 6 CLOSED

Thanks for bringing this to my attention.
I'm suspicious this is a configuration issue rather than a preprocessor issue, but I'll look into it asap.

from karma-rollup-preprocessor.

I am running into this same issue. When I have karma set to watch my test directory then any change to a test file cause it to be rebuilt with the rollup preprocessor, but changes to the src files imported by the test files are never recompiled. I have to manually kill and restart karma each time I change a src file which is very frustrating.

Any ideas on how to fix this?

from karma-rollup-preprocessor.

Same behavior here. When test file is updated, rollup preprocessor does its job perfectly, otherwise when an src file is updated, rollup preprocessor does not run at all (it seems to not be executed by karma).

@ccampbell A quick workaround, instead of restarting karma, is to save your test file again to force rollup preprocessor to do its magic again.

from karma-rollup-preprocessor.

@mjeanroy in my experience, that only works to recompile the test code and not the src code.

What I have found is that if my karma config is referencing {pattern: 'test/*-test.js'} in the files section then saving a src file does nothing, but a test file will rebuild the files in the test directory.

If my karma config is referencing {patten: 'test/specificfile-test.js'} in the files section then saving a src file does nothing, but a test file will rebuild both the files in the test directory as well as the files in the src directory. So I have been using that when I want to have the tests run as I'm changing src code, but it is a bit annoying.

from karma-rollup-preprocessor.

This problem is picky. Here's a SO post I made on it as I've tried several workarounds.
I have also created a repository for demonstrating the issue.

from karma-rollup-preprocessor.

Edit: This has been fixed in the latest 3.0.0 release @CrowdHailer @ccampbell @mjeanroy.

I believe I've wrapped my head around the problem, thanks to @brianmhunt and his work.

Let's say we have 2 files:

// foo.js
export { data: 'bar' }

// foo.spec.js
import foo from './foo.js';

expect(foo).to.be.defined;

We would end up with a new temporary file served to the Karma browser, something like this:

// foo.spec.bundle.js
var foo = { data: 'bar' };

expect(foo).to.be.defined;

Rollup simply imports the contents of the files it finds in the import statement at the time of bundling. So when we change foo.js...

// foo.js
- export { data: 'bar' }
+ export { data: 'wunderbar' }

Karma will re-run our tests because we've set it up to watch all our files, but because foo.spec.js hasn't changed, our test bundle is still the same:

// foo.spec.bundle.js
var foo = { data: 'bar' };

expect(foo).to.be.defined;

But if we update foo.spec.js:

// foo.spec.js
import foo from './foo.js';

expect(foo).to.be.defined;
+expect(foo.data).to.equal('wunderbar');

It will trigger Rollup to re-bundle that file, and it will grab foo.js again (which has changed since the last time it bundled) and we'll get:

// foo.spec.bundle.js
var foo = { data: 'wunderbar' };

expect(foo).to.be.defined;
expect(foo.data).to.equal('wunderbar');

The reason @brianmhunt's PR solves this problem, is because it forces all bundles to be recompiled (by manually changing the modified and accessed times) when any of the files they import change.

So in our above example, when foo.js was changed, it would change the accessed and modified times of foo.spec.js, triggering Karma's watch handler to rebundle foo.spec.bundle.js 🎉

from karma-rollup-preprocessor.