Replace vendored toml with tomli for TOML v1.0.0 compat

[hukkin]

Closes #10034

[hukkin]

I've got a few questions/notes here myself!

[pradyunsg]

You should run nox -s vendoring, which runs the automation we have for doing the vendoring.

The CI job for vendoring runs it as well, and shows how what you've made in the patch is different from what the automation generates.

[hukkin]

You should run nox -s vendoring

Thanks! For reasons unknown to me, nox failed to install vendoring:

ERROR: No matching distribution found for vendoring>=0.3.0

But tox -e vendoring worked like a charm.

[pradyunsg]

Let's hold off on merging this until tomli stabilises. I don't think there's a hurry in vendoring this, and given the current frequency of enhancements being made to tomli's error reporting and edge case handling, it can't hurt to wait until closer to our release to update and merge this.

[uranusjr]

One nit, otherwise LGTM.

[hukkin]

Let's hold off on merging this until tomli stabilises...

Makes sense. At this stage the parser passes all tests by BurntSushi and iarna plus a good amount of extra tests specially crafted for cases the aforementioned test suites did not cover. So I'm fairly confident and have stopped actively searching for bugs now. That said, the parser is still brand new...

One nit, otherwise LGTM.

Thanks, commited!

[pradyunsg]

@hukkin Could you squash the commits in this PR, to be something like the following?

• Vendor tomli v1.0.3
• Replace toml usage with tomli
• Unvendor toml, since it's no longer used
• {all the other misc changes}

This would separate manual changes from automation-driven changes which is basically always a good idea -- that'll make it easier to manage this PR, making it easier to ensure that the individual changes are accurate.

This is no longer a concern.

[hukkin]

Just pushed an improved commit history @pradyunsg

[uranusjr]

@pypa/pip-committers do we want this in 21.2?

[pradyunsg]

I like how that sounds! The sooner we adopt TOML 1.0, the sooner the rest of the ecosystem can start adopting it.

[uranusjr]

Let’s do it then. I’ll merge as soon as @hukkin confirms this is good to go.

[hukkin]

@uranusjr This is ready to merge from my side

[uranusjr]

Awesome!