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no-object-methods-on-collections

Disallow using Object methods on Map and Set instances.

💭

This rule requires type information to run, which comes with performance tradeoffs.

Methods like Object.entries(), Object.keys(), and Object.values() can be used work with collections of data stored in objects. However, when working with Map or Set objects, even though they are collections, using these methods are a mistake because they do not properly write to (in the case of Object.assign()) or read from the object.

This rule prevents such methods from being used on Map and Set objects.

	console.log(Object.values(new Set('abc')));
	Object.assign(new Map(), { k: 'v' });
Open in Playground
eslint.config.mjs
export default tseslint.config({
  rules: {
    "@typescript-eslint/no-object-methods-on-collections": "error"
  }
});

Try this rule in the playground ↗

Options​

This rule is not configurable.

When Not To Use It​

Type checked lint rules are more powerful than traditional lint rules, but also require configuring type checked linting.

See Troubleshooting > Linting with Type Information > Performance if you experience performance degradations after enabling type checked rules.

Resources​