chore(CI): add tests for ESLint 7

[MichaelDeBoey]

ESLint v7.0.0 is released 🎉

Dependencies should be compatible with ESLint 7 too before we can merge this one:

• eslint-plugin-es (Support ESLint 7.x eslint-plugin-es#29)
  • feat: Support ESLint 7.x eslint-plugin-es#30
  • v3.0.1
• eslint-utils (Support ESLint 7.x eslint-utils#6)
  • feat: Support ESLint 7.x eslint-utils#7
  • v3.0.0

devDependency compatibility with ESLint 7:

• @mysticatea/eslint-plugin (Support ESLint 7.x eslint-plugin#28)
  • feat: support ESLint 7.x eslint-plugin#29
  • Release

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Closes #223

This branch is dependent on #305, #306, #307, #308 & #309

[weyert]

Any plans to progress this feature/pull request?

[MichaelDeBoey]

@weyert We still have to wait for mysticatea/eslint-utils#7 before we can start going forward with this one 🙂

[MichaelDeBoey]

Since all tests are green for ESLint 7.x, I think we can merge this one without mysticatea/eslint-utils#7 being merged 🙂

[pragmaticivan]

Howdy! any plans for merging this PR? I see it was ready to be merged 22 days ago

[MichaelDeBoey]

@mysticatea All tests are green (locally), so I think we can merge this one 🙂

CC/ @sosukesuzuki @ota-meshi

[voxpelli]

Would it be possible to drop this down from a daunting 42 file change to something more narrowed and easier to review?

Looks like most of the diff is to sort object definitions by key and to eg. restructure the way that the CI setup is done? (Moving from an exclude to an include)

To really make reviewing and merging simpler, keeping the diff to a minimal is good 👍

[MichaelDeBoey]

@voxpelli Most of the changes are due to updating @mysticatea/eslint-plugin.

Would it help if I created separate commits in order to understand a bit better what's happening?

[voxpelli]

The smaller chunks the easier to review and to understand the scope, so yes, one PR per such scope would be nice 👍

[MichaelDeBoey]

@voxpelli As I said before: doing everything in separate PRs won't be possible, as of the breaking changes

But I can create separate commits if that makes it easier for you

[MichaelDeBoey]

@voxpelli I've merged #305, #306, #307, #308 & #309 and added one last commit to support ESLint v7.x