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Rslint

    no-restricted-types

    Configuration

    rslint.config.ts
    import { defineConfig, ts } from '@rslint/core';

export default defineConfig([
  ts.configs.recommended,
  {
    rules: {
      '@typescript-eslint/no-restricted-types': 'error',
    },
  },
]);

    Rule Details

    Disallow specified types. The rule reports any usage of a type whose name matches a key in the configured types map. Names are compared after stripping all whitespace, so a source-side Banned<A, B> matches a configured key of Banned<A,B> (and a configured key of NS.Banned matches a source-side NS.Banned).

    The rule recognizes these type-syntax forms:

    • Primitive type keywords (bigint, boolean, never, null, number, object, string, symbol, undefined, unknown, void).
    • Type references — both bare (Banned, NS.Banned) and parameterized (Banned<A>, NS.Banned<A>).
    • The empty tuple type [].
    • The empty type literal {}.
    • Heritage references — class X implements Banned and interface X extends Banned.

    Each entry in types pairs a type name with one of:

    • true — ban with the default message.
    • false or null — explicitly do not ban this name.
    • A string — ban with the string appended to the default message.
    • An object { message?: string, fixWith?: string, suggest?: string[] } — ban with an extra message, an optional auto-fix replacement, and/or one or more editor suggestions.

    Examples of incorrect code for this rule with { "types": { "Banned": "Use Ok instead." } }:

    { "@typescript-eslint/no-restricted-types": ["error", { "types": { "Banned": "Use Ok instead." } }] }
    let value: Banned;

    Examples of correct code for this rule with { "types": { "Banned": "Use Ok instead." } }:

    { "@typescript-eslint/no-restricted-types": ["error", { "types": { "Banned": "Use Ok instead." } }] }
    let value: Ok;

    Examples of incorrect code for this rule with { "types": { "Banned": { "fixWith": "Ok", "message": "Use Ok instead." } } }:

    { "@typescript-eslint/no-restricted-types": ["error", { "types": { "Banned": { "fixWith": "Ok", "message": "Use Ok instead." } } }] }
    let value: Banned;

    The auto-fix rewrites the type reference to Ok.

    Examples of incorrect code for this rule with { "types": { "[]": "Use unknown[] instead." } }:

    { "@typescript-eslint/no-restricted-types": ["error", { "types": { "[]": "Use unknown[] instead." } }] }
    let value: [];

    Original Documentation