Approach to get a full working isObject test in JavaScript

isObject.js

/**
 * Returns true, if x is a pure Object (not a descendant of Object)
 * Test cases:
 *  assert.isFalse(isObject(''));
 *  assert.isFalse(isObject('abc'));
 *  assert.isFalse(isObject([]));
 *  assert.isFalse(isObject([1,2,3]));
 *  assert.isFalse(isObject(1));
 *  assert.isFalse(isObject(1.4));
 *  assert.isFalse(isObject(function () {}));
 *  assert.isFalse(isObject(true));
 *  assert.isFalse(isObject(false));
 *  assert.isFalse(isObject(new Map()));
 *  assert.isFalse(isObject(new Set()));
 *
 *  assert.isTrue(isObject(new Object()));
 *  assert.isTrue(isObject({}));
 *  assert.isTrue(isObject(Object.create({})));
 *  assert.isTrue(isObject({ foo: 'bar' }));
 **/
export const isObject = x => !!x &&
		!Array.isArray(x) &&
		typeof x === 'object' &&
		x.constructor.name.indexOf('Object') > -1 &&
		x === Object(x);