#prefer-rs-mocked

#Configuration

import { defineConfig, rstestPlugin } from '@rslint/core';

export default defineConfig([
  rstestPlugin.configs.recommended,
  {
    rules: {
      'rstest/prefer-rs-mocked': 'error',
    },
  },
]);

#Rule Details

This rule requires rs.mocked() instead of mock type assertions. Type assertions such as as Mock, as Mocked<T>, and as MockInstance discard the original function signature, while mocked() adds mock methods without losing its parameter and return types.

The rule recognizes these types when they are imported from @rstest/core or rstack/test, including renamed imports and type-only imports. Other types with the same names, namespace-qualified types, satisfies expressions, and variable type annotations are not reported.

#Incorrect

import type { Mock } from '@rstest/core';

(loadUser as Mock).mockReturnValue({ id: 1, name: 'Ada' });

#Correct

import { rs } from '@rstest/core';

rs.mocked(loadUser).mockReturnValue({ id: 1, name: 'Ada' });

#Autofix

The autofix replaces the complete assertion with rs.mocked(expression) or rstest.mocked(expression). It uses an imported utilities namespace when present, written under the name the import binds, so an aliased import is used under its alias. A type-only import binds no value and is not used. Otherwise, both global names must be free; the fix follows the spelling already used by the file and defaults to rs. No autofix is offered when an unrelated declaration makes the available global namespace uncertain.

#Suggestions

When no imported or global utilities namespace can be chosen safely but the file already uses import.meta.rstest, the rule suggests replacing the assertion with import.meta.rstest.rs.mocked(expression). If none of these references can be used safely, the assertion is reported without an edit.