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 FAIL  test/jest/module-a.spec.js
  ● Test suite failed to run

    ● Invalid return value:
      `process()` or/and `processAsync()` method of code transformer found at
      "/Users/erin/grit/github.com/make-files/makefiles/test/pkg-js/npm/node_modules/es-jest/transform.js"
      should return an object or a Promise resolving to an object. The object
      must have `code` property with a string of processed code.
      This error may be caused by a breaking change in Jest 28:
      https://jestjs.io/docs/upgrading-to-jest28#transformer
      Code Transformation Documentation:
      https://jestjs.io/docs/code-transformation


      at ScriptTransformer._buildTransformResult (node_modules/@jest/transform/build/ScriptTransformer.js:507:15)
      at ScriptTransformer.transformSource (node_modules/@jest/transform/build/ScriptTransformer.js:628:17)
      at ScriptTransformer._transformAndBuildScript (node_modules/@jest/transform/build/ScriptTransformer.js:765:40)
      at ScriptTransformer.transform (node_modules/@jest/transform/build/ScriptTransformer.js:822:19)

// file myClass.ts
export default class MyClass {
    doSomething() {
        return 'foo'
    }
}

// file test/myClass.test.ts
import MyClass from '../myClass';
jest.mock('../myClass');

const MockedMyClass = jest.mocked(MyClass, true);

// fails here on TypeError: MockedMyClass.mockImplementation is not a function
MockedMyClass.mockImplementation(() => ({
  doSomething: () => 'bar',
}))

test('MyClass', () => {
  const myClass = new MyClass();
  expect(myClass.doSomething()).toEqual('bar')
})