Configurable Extension Filter

[dfreeman]

Currently it appears the .js extension filter is hard coded when traversing a directory hierarchy for files to lint. It would be nice for this to be configurable, particularly as ES6 support starts to come up.
As an example use case, we're currently using .js.es6 as an extension for files that have ES6 module syntax transpiled to AMD, and it would be nice to be able to lint the original source files.

[nzakas]

Can you explain the use case a bit more? I'm not quite following. ESLint can't understand ES6 syntax (yet) so it seems like you'd want to skip over .js.es6 files.

[dfreeman]

For the moment that's absolutely the case. More just interested in getting this on the radar for whenever ES6 support does land.

I believe the repo README says ES6 would be revisited after the 0.5.0 release, so I was hopeful there might be some movement on that front soon :)

[nzakas]

Yes, we are basically waiting for ES6 support in Esprima to land.

[nzakas]

Working on this.

[SimenB]

Is it possible to define the extensions-array in .eslintrc? .jsx files are not picked up even though ecmaFeatures contains jsx: true. If I give the CLI just the jsx-file directly it's linted, but giving it the directory containing a .jsx-file it's not linted.

Current workaround is just to name the file .js, of course, but we'd like to use the jsx-extension

[mwilc0x]

I'm seeing the same behavior as @SimenB where the ecmaFeatures: { jsx: true } is not working for including jsx files.

If possible, I'd like to stick with .jsx extension because it is offering the best dev experience with the ide my team is using. Having eslint support for this would be nice.

[ilyavolodin]

You have to use --ext CLI option in order to lint jsx files.

[mwilc0x]

Thanks @ilyavolodin, --ext=js --ext=jsx does work. Is there a way to configure this from .eslintrc? Thanks.

[SimenB]

I tried digging in the source, and it seems .eslintrc is only read AFTER a file is loaded. So I'm guessing no, but don't quote me on that.
I'm guessing that's the reason .eslintignore is a separate file as well.

For IntelliJ (if that's what you're using), you can pass CLI arguments.

But it'd definitely be preferable to have that in the config...

EDIT: I don't suppose eslint could test against /.jsx?$/. Doesn't really scale when the next cool js-extension pops up, though...

[ilyavolodin]

You are correct. We can't configure this through .eslintrc because we only read configuration after we build up a list of files to lint. And I think there's an open issue somewhere to make jsx files be linted by default.