Self test

A self test to a 4-methods inheritance

var A = function (val) {
	if (val) {
		this.val = val;
	}
}.define({
	method1: function (x, y, z) {
		this.x = x;
		this.y = y;
		this.z = z;
	}
});


//Follow derrivations using fastClass
var B = A.fastClass(function (base, baseCtor) {
	this.constructor = function (val) { baseCtor.call(this, val) },
	this.method1 = function (y, z) {
		base.method1.call(this, 'x', y, z);
	}
});
var C = B.fastClass(function (base, baseCtor) {
	this.constructor = function (val) { baseCtor.call(this, val) },
	this.method1 = function (z) {
		base.method1.call(this, 'y', z);
	}
});

var D = C.fastClass(function (base, baseCtor) {
	this.constructor = function (val) { baseCtor.call(this, val) },
	this.method1 = function (z) {
		base.method1.call(this, z);
	}
});

selfTest();

function selfTest() {
	window.a = new A("a");
	a.method1("x", "y", "z");
	console.assert(a.x == "x", "a.x should be set to 'x'");
	console.assert(a.y == "y", "a.y should be set to 'y'");
	console.assert(a.z == "z", "a.z should be set to 'z'");
	window.b = new B("b");
	b.method1("y", "z");
	console.assert(b.x == "x", "b.x should be set to 'x'");
	console.assert(b.y == "y", "b.y should be set to 'y'");
	console.assert(b.z == "z", "b.z should be set to 'z'");
	window.c = new C("c");
	c.method1("z");
	console.assert(c.x == "x", "c.x should be set to 'x'");
	console.assert(c.y == "y", "c.y should be set to 'y'");
	console.assert(c.z == "z", "c.z should be set to 'z'");

	window.d = new D("d");
	d.method1("w");
	console.assert(d.x == "x", "d.x should be set to 'x'");
	console.assert(d.y == "y", "d.y should be set to 'y'");
	console.assert(d.z == "w", "d.z should be set to 'w'");

	var expecteds = {
		"d instanceof A": true,
		"d instanceof B": true,
		"d instanceof C": true,
		"d instanceof D": true,
		"c instanceof A": true,
		"c instanceof B": true,
		"c instanceof C": true,
		"b instanceof A": true,
		"b instanceof B": true,
		"b instanceof C": false,
		"a instanceof A": true,
		"a instanceof B": false,
		"a instanceof C": false,
		"A.prototype.constructor === a.constructor && a.constructor === A": true,
		"B.prototype.constructor === b.constructor && b.constructor === B": true,
		"C.prototype.constructor === c.constructor && c.constructor === C": true,
		"D.prototype.constructor === d.constructor && d.constructor === D": true,
	}
	for (var expectedKey in expecteds) {
		var expected = expecteds[expectedKey];
		var actual = eval(expectedKey);//using eval for quick demo self test purposing -- using eval is not recommended otherwise
		console.assert(!(expected ^ actual), expectedKey + " expected: " + expected + ", actual: " + actual);
	}
}
console.log("If there are no asserts in the console then all tests have passed! yey :)")

Copy paste this to your project and it should not trigger any errors to the console.

Or you can view it live on this JSFiddle