Add oop module to allow object oriented programming with correct inhe…

…ritance

oop.js

@@ -0,0 +1,23 @@
+define(function () {
+
+    // Source: http://stackoverflow.com/a/4389429/1178541
+
+    var oop = {};
+
+    // This is a constructor that is used to setup inheritance without
+    // invoking the base's constructor. It does nothing, so it doesn't
+    // create properties on the prototype like our previous example did
+
+    function surrogateCtor() {}
+
+    oop.extend = function (base, sub) {
+        // Copy the prototype from the base to setup inheritance
+        surrogateCtor.prototype = base.prototype;
+        // Tricky huh?
+        sub.prototype = new surrogateCtor();
+        // Remember the constructor property was set wrong, let's fix it
+        sub.prototype.constructor = sub;
+    }
+
+    return oop;
+});

test/oopSpec.js

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+define(["sugar-web/oop"], function (oop) {
+
+    describe("oop", function () {
+
+        Person = function (name) {
+            this.name = name;
+        };
+
+        Person.prototype.sayHi = function () {
+            return "Hi! I'm " + this.name;
+        };
+
+        Person.prototype.tellMore = function () {};
+
+        SuperHero = function (name, power) {
+            Person.call(this, name);
+            this.power = power;
+        };
+
+        oop.extend(Person, SuperHero);
+
+        SuperHero.prototype.tellMore = function () {
+            return Person.prototype.sayHi.call(this) +
+                ", and I can " + this.power;
+        };
+
+        var bob = new Person("Bob");
+        var superman = new SuperHero("Superman", "fly");
+
+        it("should consider instanceof", function () {
+            expect(bob instanceof Person).toBe(true);
+            expect(superman instanceof Person).toBe(true);
+            expect(superman instanceof SuperHero).toBe(true);
+        });
+
+        it("should pass parameters to the parent constructor", function () {
+            expect(bob.name).toBe("Bob");
+            expect(superman.name).toBe("Superman");
+        });
+
+        it("should add new propierties", function () {
+            expect(bob.power).toBeUndefined();
+            expect(superman.power).toBe("fly");
+        });
+
+        it("should call parents methods", function () {
+            expect(bob.sayHi()).toBe("Hi! I'm Bob");
+            expect(superman.sayHi()).toBe("Hi! I'm Superman");
+        });
+
+        it("should redefine parents methods", function () {
+            expect(bob.tellMore()).toBeUndefined();
+            expect(superman.tellMore()).toBe("Hi! I'm Superman, and I can fly");
+        });
+    });
+
+});