quixote/src/assertable.js

CSS unit and integration testing

// Copyright (c) 2015 Titanium I.T. LLC. All rights reserved. For license, see "README" or "LICENSE" file.
"use strict";

var ensure = require("./util/ensure.js");
var oop = require("./util/oop.js");
var shim = require("./util/shim.js");

var Me = module.exports = function Assertable() {
	ensure.unreachable("Assertable is abstract and should not be constructed directly.");
};
Me.extend = oop.extendFn(Me);
oop.makeAbstract(Me, []);

Me.prototype.assert = function assert(expected, message) {
	ensure.signature(arguments, [ Object, [undefined, String] ]);
	if (message === undefined) message = "Differences found";

	var diff = this.diff(expected);
	if (diff !== "") throw new Error(message + ":\n" + diff + "\n");
};

Me.prototype.diff = function diff(expected) {
	ensure.signature(arguments, [ Object ]);

	var result = [];
	var keys = shim.Object.keys(expected);
	var key, oneDiff, descriptor;
	for (var i = 0; i < keys.length; i++) {
		key = keys[i];
		descriptor = this[key];
		ensure.that(
				descriptor !== undefined,
				this + " doesn't have a property named '" + key + "'. Did you misspell it?"
		);
		oneDiff = descriptor.diff(expected[key]);
		if (oneDiff !== "") result.push(oneDiff);
	}

	return result.join("\n");
};