Extract the io_file POSIX API into a separate package

[brianquinlan]

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[devoncarew]

@brianquinlan - for the review - is this mostly a mechanical change? Create a new labs package, move content into it, and reference it from the existing package?

[brianquinlan]

@brianquinlan - for the review - is this mostly a mechanical change? Create a new labs package, move content into it, and reference it from the existing package?

Yes. I added a very simple test (which I will improve in follow-up PRs) and a README file. Everything else is a move from the existing location or was created from dart create.

BTW, I don't actually want a good name for this package - hopefully someone will fork this and take whatever the best available name is ;-)

[devoncarew]

lgtm w/ some in-line comments

[devoncarew]

I'd try using something like ^0.1.0 here, and add a dependency_overrides section further down:

dependency_overrides:
  unix_api:
    path: ../unix_api

[brianquinlan]

Done.

[brianquinlan]

I changed to back because changing this also trickles into the mobile_test subproject and it seemed better to contain the path reference here. WDYT?

[devoncarew]

Well, it's not normally how we'd try and reference a package - it'll mean that io_file won't be useable outside this repo. I'm not sure what the issue is w/ the subproject.

Feel free to use your best judgement here though; we're not trying to ship this currently. If you do use a relative reference into this repo, you might leave a comment that this isn't our normal practice.

[devoncarew]

Well, it's not normally how we'd try and reference a package - it'll mean that io_file won't be useable outside this repo. I'm not sure what the issue is w/ the subproject.

Feel free to use your best judgement here though; we're not trying to ship this currently. If you do use a relative reference into this repo, you might leave a comment that this isn't our normal practice.