@jsenv/eslint-config/src/internal/composeTwoObjects.js

Create ESLint configuration for any project

export const composeTwoObjects = (first, second, composerMap) => {
  const composed = {};

  const firstKeys = Object.keys(first);
  const secondKeys = Object.keys(second);
  Object.keys(first).forEach((key) => {
    composed[key] = secondKeys.includes(key)
      ? composeTwoValues(first[key], second[key], composerMap[key])
      : first[key];
  });
  Object.keys(second).forEach((key) => {
    if (!firstKeys.includes(key)) {
      composed[key] = second[key];
    }
  });

  return composed;
};

const composeTwoValues = (firstValue, secondValue, composer) => {
  if (composer) {
    return composer(firstValue, secondValue);
  }
  return secondValue;
};