Cypress Custom TypeScript Command is not a Function

Question

I am implementing a custom Cypress command in TypeScript:

// support/commands.ts
const login = () => {
    console.log(\'Logging in...\');
};

Cypress.Command         


        

Answer 1

I fixed it by adding index.d.ts file in my commands folder. In this file I added something like this:

import { MyCustomType } from '../Types';

declare global {
  namespace Cypress {
    interface Chainable {
      login(): Chainable;
    }
  }
}

If You don't import or export anything, just omit global namespace declaration:

declare namespace Cypress {
  interface Chainable {
    login(): Chainable;
  }
}

Keep in mind that it won't work with Typesciprt < 2.3, becuase default generics type has to be supported.