I have a function declaration that I would like to add to my jest.setup.js file for several projects.

How can I write a jscodeshift script to add this function declaration to the end of any specified file?

// Establish API mocking before all tests.
beforeAll(() => {
  server.listen({
    onUnhandledRequest: "bypass",
  });
});

This is what I’ve attempted so far

export default (fileInfo, api) => {
  const j = api.jscodeshift;
  const root = j(fileInfo.source);

  const codeToAdd = `
        // Establish API mocking before all tests.
        beforeAll(() => {
            server.listen({
                onUnhandledRequest: "bypass",
            });
        });
      `;

  // Convert the code string to AST nodes
  const newCodeAst = j(codeToAdd);


  // Find the end of the file and insert the new code
  root.find(j.Program).forEach((path) => {
    path.node.body.push(...newCodeAst.nodes());
  });

  return root.toSource();
};

but I’m getting this error when I try to use the script to append the function declaration to the end of a project’s jest.setup.js file

 ERR ./jest-no-console/jest.setup.js Transformation error ({ type: File, start: 0, end: 408, loc: [object Object], errors: , program: [object Object], tokens: [object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object] } does not match type string)
Error: { type: File, start: 0, end: 408, loc: [object Object], errors: , program: [object Object], tokens: [object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object] } does not match type string
    at PredicateType.BaseType.assert

What is wrong with my script?

Thank you