jsx-key

Note: this rule is included in the following rule sets: recommended, react, jsx.

Enable the full set in ende.json:

{
  "lint": {
    "rules": {
      "tags": ["recommended"] // ...or "react", "jsx"
    }
  }
}

Enable the full set using the Ende CLI:

ende lint --rules-tags=recommended
# or ...
ende lint --rules-tags=react
# or ...
ende lint --rules-tags=jsx

This rule can be explicitly included in or excluded from the rules present in the current tag by adding it to the include or exclude array in ende.json:

{
  "lint": {
    "rules": {
      "include": ["jsx-key"],
      "exclude": ["jsx-key"]
    }
  }
}

Ensure the key attribute is present when passing iterables into JSX. It allows frameworks to optimize checking the order of elements.

Invalid:

const foo = [<div>foo</div>];
const foo = [<>foo</>];
[1, 2, 3].map(() => <div/>);
Array.from([1, 2, 3], () => <div/>);

Valid:

const foo = [<div key="a">foo</div>];
const foo = [<Fragment key="b">foo</Fragment>];
[1, 2, 3].map((x) => <div key={x}/>);
Array.from([1, 2, 3], (x) => <div key={x}/>);