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eslint/prefer-object-spread Style

🛠️ An auto-fix is available for this rule.

What it does

Disallow using Object.assign with an object literal as the first argument and prefer the use of object spread instead

Why is this bad?

When Object.assign is called using an object literal as the first argument, this rule requires using the object spread syntax instead. This rule also warns on cases where an Object.assign call is made using a single argument that is an object literal, in this case, the Object.assign call is not needed.

Examples

Examples of incorrect code for this rule:

js
Object.assign({}, foo);

Object.assign({}, { foo: "bar" });

Object.assign({ foo: "bar" }, baz);

Object.assign({}, baz, { foo: "bar" });

Object.assign({}, { ...baz });

// Object.assign with a single argument that is an object literal
Object.assign({});

Object.assign({ foo: bar });

Examples of correct code for this rule:

js
({ ...foo });

({ ...baz, foo: "bar" });

// Any Object.assign call without an object literal as the first argument
Object.assign(foo, { bar: baz });

Object.assign(foo, bar);

Object.assign(foo, { bar, baz });

Object.assign(foo, { ...baz });

How to use

To enable this rule in the CLI or using the config file, you can use:

bash
oxlint --deny prefer-object-spread
json
{
  "rules": {
    "prefer-object-spread": "error"
  }
}

References

Released under the MIT License.