This commit updates eslint from v4 to v6. In doing so, I've moved off of
the create-react-app base eslint config. We were on an old version (v2)
and it doesn't make sense to update to v4, as in v4 create-react-app
uses typescript. Also, it didn't make sense to stay on
create-react-app's v2 config, because then it had unmet peer dependency
constraints on old versions of eslint.
Instead, I've moved us to use the default rules for eslint,
eslint-plugin-react, and eslint-plugin-flowtype.
I also made some changes to the codebase to satisfy the new lint rules
that came with this change.
Test plan: `yarn test` passes.
I wanted to add two new flowtype lint rules. However, as seen in #853
and #854, these rules don't work very well. As such, I'm giving up on
those two and removing the TODOs.
Test plan: n/a
This commit upgrades the flow-type eslint plugin to latest, and writes
new rules into the eslintrc. To keep the diff clean, the rules are
disabled: I will turn them on individually (fixing errors) in followon
commits.
Test plan: `yarn test`.
Uncommenting the lines produces many lint errors (but the linter still operates as expected).
Summary:
In fact, a constructor that only calls `super` is useful: it specifies
the API for constructing an object of a given class without needing to
traverse its prototype chain. (That constructors are inherited at all is
arguably a design flaw.)
Test Plan:
None.
wchargin-branch: yes-useful-constructor
Summary:
Even though it’s not really a source file, and it lives at the
repository root, it might as well have typing to make sure that we don’t
do anything really dumb.
Test Plan:
`yarn flow` still passes.
wchargin-branch: flow-eslintrc
Test Plan:
Run `yarn lint` and `yarn travis` and observe success. Add something
that triggers a lint warning, like `const zzz = 3;`; re-run and observe
failures.
wchargin-branch: lint
Dandelion Mané
William Chargin