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eslint/no-dupe-keys Correctness

This rule is turned on by default.

What it does

Disallow duplicate keys in object literals.

This rule can be disabled for TypeScript code, as the TypeScript compiler enforces this check.

Why is this bad?

Multiple properties with the same key in object literals can cause unexpected behavior in your application.

Examples

Examples of incorrect code for this rule:

js
var foo = {
    bar: "baz",
    bar: "qux"
};

var foo = {
    "bar": "baz",
    bar: "qux"
};

var foo = {
    0x1: "baz",
    1: "qux"
};

Examples of correct code for this rule:

js
var foo = {
    bar: "baz",
    qux: "qux"
};

How to use

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

json
{
    "rules": {
        "no-dupe-keys": "error"
    }
}
bash
oxlint --deny no-dupe-keys

References

Released under the MIT License.