Add documentation for filtering (grep, invert, tags, skipTags)

[rprieto]

Documents the new --tags and --skip-tags options from pull request #1445.

[dasilvacontin]

Btw, it there a way to only run tests tagged both with tag 'x' and tag 'y'?

[rprieto]

That's something we talked about early on at #1445, with a special syntax like api+integration, but it raised a few questions (can you do (api AND integration) OR app, what about (api AND integration) not (slow OR redis)...).

I think @boneskull's comment was "make it as simple as possible", which I think is nice. So we ended up with --tags x,y,z to run tests with either tags, and --skip-tags x,y,z to skip tests with either tags.

It's true that it would be nice, since "run api integration tests" sounds like a common scenario. Another approach could have been x,y,z to mean AND, and repeat the --tags command to OR them together:

# run tests with (api AND integration) OR (app AND integration)
# exclude tests with (unit AND slow) OR (redis)
mocha --tags api,integration --tags app,integration --skip-tags unit,slow --skip-tags redis

I'm happy to revisit the PR if the Mocha team thinks it's useful. Good news is there's lots of tests so it should be an easy change 😃

[dasilvacontin]

I continue discussing at #1445.

[rprieto]

@dasilvacontin I added a new commit (docs only) to show the + operator. If that's what you had in mind I'll have a go at the implementation.

[dasilvacontin]

LGTM, though it would be desirable to get a 👍 from either @boneskull or @travisjeffery since I'm not really a maintainer. 😅

[rprieto]

Haha I didn't know that. Yep will hold off for now!

[dasilvacontin]

Haha, no problemo. Just check for the Collaborator/Owner badge. :)

I hope you get an answer soon!

[boneskull]

I'm pretty overloaded atm. Hopefully will have some time next week around xmas to look at stuff.

[dasilvacontin]

don't worry @boneskull! holidays are coming :)

[rprieto]

Happy new year! I'm keen to revive this PR, see what everyone thinks (either the simple --tags a,b,c version, or the slightly more complex but more powerful --tags a+b,c+d version)

[rprieto]

Fair enough, we can probably revisit this if required. Does this mean any activity on #1445? :)

[jbnicolai]

Ah, no @rprieto - sorry for the confusion. GH closed this PR as it was directed at the now moved mochajs/mocha#gh-pages branch, which now resides under mochajs/mochajs.github.io#master.

I'll tag this for follow-up, and move it over to the new repo as soon as possible.

[jbnicolai]

And in response to your other question: #1445 is definitely still on my radar. We've been cutting our way through the long-lived PRs for a few days now, and we're down to 17 right now (from 35+ a few days back). So we'll get there :)

[rprieto]

Haha right, no problem then :) Nice work on the PRs!