Add includeDirs to WalkOptions

[nayeemrmn]

Towards API improvements in the test runner (touched upon here denoland/deno#2948 (comment)).
Also just a useful feature.

Fixes outdated documentation. cc @bartlomieju.

[bartlomieju]

So I guess with the includeDirs option you would want to use like this: deno test src/. Then check if walk found any files/dirs, if one of found entries is a directory you'd apply default globs again. Am I understanding it correctly?

EDIT: Additionally I think that passing globs to test runner is not really ergonomic... If I do deno test **/*_test.ts then **/*_test.ts glob is expanded by my shell and test runner is passed a list of actual paths. To pass actual glob to test runner I have to write deno test \*\*\/\*_test.ts. So your solution might be more ergonomic 👍

[nayeemrmn]

So I guess with the includeDirs option you would want to use like this: deno test src/. Then check if walk found any files/dirs, if one of found entries is a directory you'd apply default globs again. Am I understanding it correctly?

@bartlomieju That's exactly correct! A nice consequence of this is that deno test could simply default to deno test . which would expand into deno test <DEFAULT GLOBS ROOTED AT .> by the above rule and have the same behaviour. Also, deno test src would behave the same as cd src && deno test!

I haven't thought the implementation through too deeply, but I think it would be really inefficient using any existing tools (though not in the most common usages), even with this change. There's a good chance walk wouldn't be used for it at all at some point, but this'll allow for an MVP.

[bartlomieju]

I haven't thought the implementation through too deeply, but I think it would be really inefficient using any existing tools (though not in the most common usages), even with this change. There's a good chance walk wouldn't be used for it at all at some point, but this'll allow for an MVP.

It sounds fine for me, but we need to test it experimentally. Could you work on MVP?

[nayeemrmn]

@ry Ready for review.

[ry]

LGTM