no-implicit-key
Rule category
Suspicious.
What it does
Prevents key from not being explicitly specified (e.g. spreading key from objects).
Why is this bad?
This makes it hard to see if the key was passed correctly to the element or where it came from.
And it’s also be proposed to be deprecated is this RFC: Deprecate spreading key from objects
Examples
This rule aims to prevent spreading key from objects.
Failing
import React from "react";
interface ExampleProps {
items: { id: string; name: string }[];
}
function Example({ items }: ExampleProps) {
return (
<ul>
{items.map((item) => {
const props = { key: item.id };
return <li {...props}>{item.name}</li>
// ^^^^^^^^^^
// - Do not use implicit 'key' props.
})}
</ul>
);
}Passing
import React from "react";
interface ExampleProps {
items: { id: string; name: string }[];
}
function Example({ items }: ExampleProps) {
return (
<ul>
{items.map((item) => (
<li key={item.id}>{item.name}</li>
))}
</ul>
);
}