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no-empty-interface

Disallow the declaration of empty interfaces.

🔧

Some problems reported by this rule are automatically fixable by the --fix ESLint command line option.

💡

Some problems reported by this rule are manually fixable by editor suggestions.

Deprecated

This rule has been deprecated in favour of the more comprehensive @typescript-eslint/no-empty-object-type rule.

An empty interface in TypeScript does very little: any non-nullable value is assignable to {}. Using an empty interface is often a sign of programmer error, such as misunderstanding the concept of {} or forgetting to fill in fields.

This rule aims to ensure that only meaningful interfaces are declared in the code.

.eslintrc.cjs
module.exports = {
  "rules": {
    "@typescript-eslint/no-empty-interface": "error"
  }
};

Try this rule in the playground ↗

Examples​

// an empty interface
interface Foo {}

// an interface with only one supertype (Bar === Foo)
interface Bar extends Foo {}

// an interface with an empty list of supertypes
interface Baz {}
Open in Playground

Options​

This rule accepts the following options:

type Options = [
  {
    /** Whether to allow empty interfaces that extend a single other interface. */
    allowSingleExtends?: boolean;
  },
];

const defaultOptions: Options = [{ allowSingleExtends: false }];

allowSingleExtends​

allowSingleExtends: true will silence warnings about extending a single interface without adding additional members

When Not To Use It​

If you don't care about having empty/meaningless interfaces, then you will not need this rule.

Resources​