Not possible to mock packages that use private APIs

[chrisvanpatten]

Description

Packages with top-level locked private APIs are not easily mockable in Jest tests by third parties.

I will fully admit even after looking through the private API code I'm not 100% sure why this is, but I've been able to reproduce it consistently, particularly with tests which depend on the @wordpress/block-editor package. It seems like something in jest.requireActual is possibly accessing these APIs in an incompatible way.

Step-by-step reproduction instructions

1. Write a Jest test depending on a mock of a package with top level private dependencies, such as @wordpress/block-editor

   
   jest.mock( '@wordpress/block-editor', () => ( {
   ...jest.requireActual( '@wordpress/block-editor' ),
   RichText: ( { value, onChange, placeholder } ) => (
       <input
           data-testid="rich-text"
           value={ value }
           onChange={ ( e ) => onChange( e.target.value ) }
           placeholder={ placeholder }
       />
   ),
   InnerBlocks: () => <div data-testid="inner-blocks">Mocked InnerBlocks</div>,
   useBlockProps: jest.fn( () => ( {} ) ),
   } ) );

describe( 'myTestSuite', () => { test( 'myTest', () => { render( );

    expect( screen.getByTestId( 'rich-text' ) ).toBeInTheDocument();
    expect( screen.getByTestId( 'inner-blocks' ) ).toBeInTheDocument();
} );

} );

2. Observe the following error in execution:

● Test suite failed to run

Cannot unlock an object that was not locked before.

  3 |
  4 | jest.mock( '@wordpress/block-editor', () => ( {
> 5 |       ...jest.requireActual( '@wordpress/block-editor' ),
    |               ^
  6 |       RichText: ( { value, onChange, placeholder } ) => (
  7 |               <input
  8 |                       data-testid="rich-text"

### Screenshots, screen recording, code snippet

_No response_

### Environment info

_No response_

### Please confirm that you have searched existing issues in the repo.

Yes

### Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

[jdamner]

+1

[VelichkoAlexander]

I encountered the same issue while also mocking @wordpress/block-editor. Gutenberg version: 16.0.0.