ESLint Plugin: Add rule no-unjustified-disable

[aduth]

This pull request seeks to add a new ESLint rule which enforces that the disabling of an ESLint rule via inline comment configuration must be accompanied by a preceding comment which justifies said disabling, using the "Disable reason:" convention already present in many occurrences in the codebase.

The reason for this rule to exist is explained in the included rule README:

If a developer finds themself in the position to disable an ESLint rule, one of the following should hold true:

• They can provide a reason the rule is not applicable or remediation steps are provided.
• The rule does not provide value for the development team.

By providing justification for the disabling of a rule, a developer communicates intent to future maintainers who may otherwise not understand the reasons it was done. Such uncertainty can needlessly discourage refactoring or unnecessarily perpetuate the configuration. Good justification can serve as a description for the conditions of its own removal.

If a rule is not valuable, it should not be part of the development team's default configuration.

Status:

The rule itself is considered complete. However, there are a large number (128) of existing problems which must first be addressed.

Testing Instructions:

Verify there are no lint errors:

npm run lint-js

Verify unit tests pass:

npm run test-unit packages/eslint-plugin/rules/__tests__/no-unjustified-disable.js

[aduth]

Relevant: https://eslint.org/blog/2020/02/whats-coming-in-eslint-7.0.0#descriptions-in-directive-comments

ESLint now supports comments as part of inline configuration, as of the latest 7.0.0 release. It's relevant for this pull request, in that it should be at the very least support—if not preferred—to document justifications this way, since it appears to be the primary use-case for the feature.

[chrisvanpatten]

I love this rule and would 100% use it!

[aduth]

This could still be useful, but the pull request itself is very stale, and I don't know that it's still a pressing concern for the project.