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no-dupe-keys

docs/src/rules/no-dupe-keys.md

10.3.0826 B
Original Source

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

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

Rule Details

This rule disallows duplicate keys in object literals.

Examples of incorrect code for this rule:

::: incorrect

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

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

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

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

:::

Examples of correct code for this rule:

::: correct

js
/*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__"
};

:::

Options

This rule has no options.