Fix jest config Nx v13

fix-jest-config.js

const path = require('path');
const fs = require('fs');
const { promisify, inspect } = require('util');

async function getAllJestConfigJsFilePaths(directory) {
  const readDir = promisify(fs.readdir);
  const stat = promisify(fs.stat);

  const files = await readDir(directory);

  const jestConfig = 'jest.config.js';

  if (files.includes(jestConfig)) {
    return path.join(directory, jestConfig);
  }

  const childFilesPromise = files
    .map((fileName) => path.join(directory, fileName))
    .map(async (path) => {
      const stats = await stat(path);
      return { stats, path };
    });

  const childFiles = await Promise.all(childFilesPromise);
  const childDirectories = childFiles.filter((file) =>
    file.stats.isDirectory()
  );

  return Promise.all(
    childDirectories.map((dir) => dir.path).map(getAllJestConfigJsFilePaths)
  );
}

function fixConfig(configObject) {
  const updates = {
    moduleFileExtensions: ['ts', 'html', 'js', 'json', 'mjs'],
    extensionsToTreatAsEsm: ['.ts'],
    setupFilesAfterEnv: ['<rootDir>/src/test-setup.ts'],
    transform: {
      '^.+\\.(ts|js|mjs|html|svg)$': 'jest-preset-angular',
    },
    snapshotSerializers: [
      'jest-preset-angular/build/serializers/no-ng-attributes',
      'jest-preset-angular/build/serializers/ng-snapshot',
      'jest-preset-angular/build/serializers/html-comment',
    ],
    transformIgnorePatterns: [
      `node_modules/(?!@angular|@ngneat/spectator|array-move|lodash-es)`,
    ],
  };

  Object.assign(configObject, updates);

  configObject.globals['ts-jest'] = {
    tsconfig: '<rootDir>/tsconfig.spec.json',
    stringifyContentPathRegex: '\\.(html|svg)$',
  };

  return configObject;
}

function writeBack(file) {
  const write = promisify(fs.writeFile);
  return write(file.path, stringify(file.config));
}

function stringify(object) {
  return `module.exports = ${inspect(object)}`;
}

(async function f() {
  // You will probably have to change this
  const appsFolder = path.join(__dirname, '..', '..', '..', 'apps');
  const libsFolder = path.join(__dirname, '..', '..', '..', 'libs');

  const jestConfigFilePaths = await Promise.all([
    ...(await getAllJestConfigJsFilePaths(appsFolder)),
    ...(await getAllJestConfigJsFilePaths(libsFolder)),
  ]);

  await Promise.all(
    jestConfigFilePaths
      .flat(5)
      .map((path) => ({ path, config: fixConfig(require(path)) }))
      .map((file) => writeBack(file))
  );
})();

Fixes all jest.config.js in a Nx workspace so they work with Nx v13. Based on this StackOverflow thread.