Changeset 7004

Timestamp:

06/11/07 19:27:12 (1 year ago)

Author:

andrew

Message:

* Added Mislav's unit tests for inheritance. The code passes current unit tests -- feel free to change base.html if you want to add more requirements.
* Added Class.add (for extending classes while preserving inheritance).
* Added the "superclass" and "subclasses" properties on classes. (i.e., Cat's superclass is Animal; Animal's subclasses are Cat and Mouse.)
* Fixed "constructor" property so that it always points back to the proper class.

Files:

• spinoffs/prototype/branches/inheritance/src/base.js (modified) (2 diffs)
• spinoffs/prototype/branches/inheritance/test/unit/base.html (modified) (2 diffs)

spinoffs/prototype/branches/inheritance/src/base.js

@@ -2 +2 @@
-var Class = {
-  extend: function(parent, methods) {
-    if (arguments.length == 1) {
-      methods = parent; parent = null;
-    }
-    var method = function() {
-      if (!Class.extending) this.initialize.apply(this, arguments);
-    };
-    
+    method.superclass = parent;
+    method.subclasses = [];
+    
-    if (typeof parent === 'function') {
-      Class.extending = true;
-      method.prototype = new parent();
+      method.prototype.constructor = method;
+
+      parent.subclasses.push(method);
+
-      delete Class.extending;
-    }
+
+    if (methods) Class.add(method, methods);
+
+    return method;    
+  },
+  
+  add: function(destination, source) {
+    for (var name in source) Class.inherit(destination, source, name);
+    return destination;
+  },
-    
-    if (methods) Class.inherit(method.prototype, methods);
-    return method;    
-  },
-  
-  inherit: function(destination, source, name) {
-
-
-
-
+
+
+
-      descendant = function() {
-        var ref = this.parent; this.parent = ancestor;
@@ -30 +39 @@
-        return result;
-      };
-
+  
-      Object.extend(descendant, {
-        valueOf:  function() { return method; },
-        toString: function() { return method.toString(); }
-      });
-
-
-
-
-
-
+
+
+
+
+
+
+
+
+
+
-      }
-    }
-    return destination;
-  },
-  
-  mixin: function(destination, source) {
-.prototype
-
-
-
-
-return Class.extend.apply(this, arguments);
+
+,
+
+
+
+}
-};
-

spinoffs/prototype/branches/inheritance/test/unit/base.html

@@ -56 +56 @@
-    
-  var globalBindTest = null;
+  
+  
+  // base class
+  var Animal = Class.create({
+    initialize: function(name) {
+      this.name = name;
+    },
+    name: "",
+    eat: function() {
+      return this.say("Yum!");
+    },
+    say: function(message) {
+      return this.name + ": " + message;
+    }
+  });
+
+  // subclass that augments a method
+  var Cat = Class.extend(Animal, {
+    eat: function(food) {
+      if (food instanceof Mouse) return this.parent();
+      else return this.say("Yuk! I only eat mice.");
+    }
+  });
+
+  // empty subclass
+  var Mouse = Class.extend(Animal);
-
-  new Test.Unit.Runner({
@@ -285 +311 @@
-        assert(Prototype.Browser.Gecko);
-      } 
+    }},
+    
+    testInstantiation: function() { with(this) { 
+      var pet = new Animal("Nibbles");
+      assertEqual("Nibbles", pet.name, "property not initialized");
+      assertEqual('Nibbles: Hi!', pet.say('Hi!'));
+      assertEqual(Animal, pet.constructor, "bad constructor reference");
+      assertUndefined(pet.superclass);
+    }},
+
+    testInheritance: function() { with(this) {
+      var tom = new Cat('Tom');
+      assertEqual(Cat, tom.constructor, "bad constructor reference");
+      assertEqual(Animal, tom.constructor.superclass, 'bad superclass reference');
+      assertEqual('Tom', tom.name);
+      assertEqual('Tom: meow', tom.say('meow'));
+      assertEqual('Tom: Yuk! I only eat mice.', tom.eat(new Animal));
+    }},
+
+    testSupercall: function() { with(this) {
+      var tom = new Cat('Tom');
+      assertEqual('Tom: Yum!', tom.eat(new Mouse));
+    }},
+
+    testAddingInstanceMethod: function() { with(this) {
+      var tom   = new Cat('Tom');
+      var jerry = new Mouse('Jerry');
+      
+      Class.add(Animal, {
+        sleep: function() {
+          return this.say('ZZZ');
+        }
+      });
+      
+      Class.add(Mouse, {
+        sleep: function() {
+          return this.parent() + " ... no, can't sleep! Gotta steal cheese!";
+        }
+      });
+      
+      assertEqual('Tom: ZZZ', tom.sleep(), "added instance method not available to subclass");
+      assertEqual("Jerry: ZZZ ... no, can't sleep! Gotta steal cheese!", jerry.sleep());
-    }}
-