* Remove redundant initial of isArray (#21163)
* Reapply prettier
* Type the isArray function with refinement support
This ensures that an argument gets refined just like it does if isArray is
used directly.
I'm not sure how to express with just a direct reference so I added a
function wrapper and confirmed that this does get inlined properly by
closure compiler.
* A few more
* Rename unit test to internal
This is not testing a bundle.
Co-authored-by: Behnam Mohammadi <itten@live.com>
In addition to `TSTypeQuery`, dependency nodes with a `TSTypeReference`
parent need to be ignored as well. Without this fix, generic type
variables will be listed as missing dependencies.
Example:
export function useFoo<T>(): (foo: T) => boolean {
return useCallback((foo: T) => false, []);
}
This will report the following issue:
React Hook useCallback has a missing dependency: 'T'. Either include
it or remove the dependency array
Closes: #19742
* Add babel parser which supports ChainExpression
* Add and fix tests for new babel eslint parser
* extract function to mark node
* refactor for compatibility with eslint v7.7.0+
* Update eslint to v7.7.0
Update hook test since eslint now supports nullish coalescing
The `startTransition` method returned from `useTransition` is a stable
method, like `dispatch` or `setState`. You should not have to specify
it as a hook dependency.
* [eslint-plugin-react-cooks] Report constant constructions
The dependency array passed to a React hook can be thought of as a list of cache keys. On each render, if any dependency is not `===` its previous value, the hook will be rerun. Constructing a new object/array/function/etc directly within your render function means that the value will be referentially unique on each render. If you then use that value as a hook dependency, that hook will get a "cache miss" on every render, making the dependency array useless.
This can be especially dangerous since it can cascade. If a hook such as `useMemo` is rerun on each render, not only are we bypassing the option to avoid potentially expensive work, but the value _returned_ by `useMemo` may end up being referentially unique on each render causing other downstream hooks or memoized components to become deoptimized.
* Fix/remove existing tests
* Don't give an autofix of wrapping object declarations
It may not be safe to just wrap the declaration of an object, since the object may get mutated.
Only offer this autofix for functions which are unlikely to get mutated.
Also, update the message to clarify that the entire construction of the value should get wrapped.
* Handle the long tail of nodes that will be referentially unique
* Catch let/var constant constructions on initial assignment
* Trim trailing whitespace
* Address feedback from @gaearon
* Rename "assignment" to "initialization"
* Add test for a constant construction used in multiple dependency arrays
* Rename internal variables
This disambiguates "optional"/"required" because that terminology is taken by optional chaining.
* Handle optional member chains
* Update comment
Co-authored-by: Ricky <rickhanlonii@gmail.com>
Co-authored-by: Ricky <rickhanlonii@gmail.com>
* Revert "Fix ExhaustiveDeps ESLint rule throwing with optional chaining (#19260)"
This reverts commit 0f84b0f02b.
* Re-add a test from #19260
* Remove all code for optional chaining support
* Consistently treat optional chaining as regular chaining
This is not ideal because our suggestions use normal chaining. But it gets rid of all current edge cases.
* Add more tests
* More consistency in treating normal and optional expressions
* Add regression tests for every occurrence of Optional*
Certain code patterns using optional chaining syntax causes
eslint-plugin-react-hooks to throw an error.
We can avoid the throw by adding some guards. I didn't read through the
code to understand how it works, I just added a guard to every place
where it threw, so maybe there is a better fix closer to the root cause
than what I have here.
In my test case, I noticed that the optional chaining that was used in
the code was not included in the suggestions description or output,
but it seems like it should be. This might make a nice future
improvement on top of this fix, so I left a TODO comment to that effect.
Fixes#19243
Dan Abramov