no-dupe-keys

Disallow duplicate keys in object literals

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

const foo = {
    bar: "baz",
    bar: "qux"
};
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Rule Details

This rule disallows duplicate keys in object literals.

Examples of incorrect code for this rule:

/*eslint no-dupe-keys: "error"*/

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

const bar = {
    "bar": "baz",
    bar: "qux"
};

const baz = {
    0x1: "baz",
    1: "qux"
};
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Examples of correct code for this rule:

/*eslint no-dupe-keys: "error"*/

const foo = {
    bar: "baz",
    quxx: "qux"
};

const obj = {
    "__proto__": baz, // defines object's prototype
    ["__proto__"]: qux // defines a property named "__proto__"
};
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Handled by TypeScript

It is safe to disable this rule when using TypeScript because TypeScript's compiler enforces this check.

Version

This rule was introduced in ESLint v0.0.9.

Resources

• Rule source
• Tests source