Add tests for running ESLint 7

[MichaelDeBoey]

ESLint v7.0.0 is released 🎉

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

• eslint-plugin-eslint-plugin (Support ESLint 7.x eslint-community/eslint-plugin-eslint-plugin#94)
  • Upgrade: eslint and other deps eslint-community/eslint-plugin-eslint-plugin#92
  • breaking: drop eslint < 7 & node.js < 10 eslint-community/eslint-plugin-eslint-plugin#95
  • v3.0.0
• eslint-plugin-node (Support ESLint 7.x mysticatea/eslint-plugin-node#223)
  • chore(CI): add tests for ESLint 7 mysticatea/eslint-plugin-node#224
  • Release
• vue-eslint-parser (Support ESLint 7.x vuejs/vue-eslint-parser#70)
  • vuejs/vue-eslint-parser@2df66e4
  • v7.1.0

---

BREAKING CHANGE: Requires Node@^10.12.x || 12.x
BREAKING CHANGE: Requires ESLint@^7.x

Closes #292

[BPScott]

Nice!

It looks like we already support eslint 7 (given our engines is >=6.0.0 and eslint peerDependency is "eslint": ">= 5.0.0", which allows for folks to run eslint 7) and there's no code change required to support eslint 7. But it's nice that we can update our CI to test that support.

It looks like all of our tests are passing. Is there anything else we need to do (I can't think of anything).

I'm curious why you mention breaking changes? It doesn't look like this is a breaking change at first glance - we don't need to touch our package.json file or make any code changes. We can leave our engines as >=6.0.0 and our dependency on eslint as >=5.0.0 so that people on those old versions can still use newer package versions.

It seems like both eslint-plugin-node and vue-eslint-parser both already do the same thing as us - the have peerDepenendencies on eslint that already allow fo the installation of eslint 7 so we don't need to wait on your PRs in those repos - as they only update the version used in the development of that package, not what is needed at runtime

[MichaelDeBoey]

@BPScott I think we can indeed just merge this one without a breaking change as all tests are passing 🙂

[BPScott]

Thanks @MichaelDeBoey.

There's no need for me to make a release of this, as we only changed CI infrastructure rather than any released code (as already mentioned - we already supported eslint 7 - but now we're testing that to prove it).