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There is already created package on npm based on this implementation! And it works for all earlier described test cases! 🙂

With function Array.isArray:

function isObject(o) {
  return o !== null && typeof o === 'object' && Array.isArray(o) === false;
}

Without function Array.isArray:

There is already created package on npm v1 based on this implementation! And it works for all earlier described test cases! 🙂

isObject won't work in case of Object.create(null) because of internal implementation of Object.create which is explained here but you can use isObject in more sophisticated implementation:

isObject won't work in case of Object.create(null) because of internal implementation of Object.create which is explained here but you can use isObject in more sophisticated implementation:

isObject won't work in case of Object.create(null) because of internal implementation of Object.create which is explained here but you can use isObject in more sophisticated implementation:

function isObject(o, strict = true) {
  if (o === null || o === undefined) {
    return false;
  }
  const instanceOfObject = o instanceof Object;
  const typeOfObject = typeof o === 'object';
  const constructorUndefined = o.constructor === undefined;
  const constructorObject = o.constructor === Object;
  const typeOfConstructorObject = typeof o.constructor === 'function';
  let r;
  if (strict === true) {
    r = (instanceOfObject || typeOfObject) && (constructorUndefined || constructorObject);
  } else {
    r = (constructorUndefined || typeOfConstructorObject);
  }
  return r;
};

There is already created package on npm based on this implementation! And it works for all earlier described test cases! 🙂