Public static properties references are now shared with subtypes

lib/class_builder.js

@@ -160,7 +160,10 @@ exports.build = function extend()
 
         prop_init      = member_builder.initMembers(),
         members        = member_builder.initMembers( prototype ),
-        static_members = member_builder.initMembers(),
+        static_members = {
+            methods: member_builder.initMembers(),
+            props:   member_builder.initMembers(),
+        }
 
         abstract_methods =
             util.clone( exports.getMeta( base ).abstractMethods )
@@ -204,11 +207,11 @@ exports.build = function extend()
     var new_class = createCtor( cname, abstract_methods, members );
 
     // closure to hold static initialization to be used later by subtypes
-    var staticInit = function( ctor )
+    var staticInit = function( ctor, inheriting )
     {
-        attachStatic( ctor, static_members, base );
+        attachStatic( ctor, static_members, base, inheriting );
     }
-    staticInit( new_class );
+    staticInit( new_class, false );
 
     attachPropInit( prototype, prop_init, members, class_id );
 
@@ -394,7 +397,11 @@ function buildMembers(
 )
 {
     var hasOwn = Array.prototype.hasOwnProperty,
-        defs   = {};
+        defs   = {},
+
+        smethods = static_members.methods,
+        sprops   = static_members.props
+    ;
 
     util.propParse( props, {
         each: function( name, value, keywords )
@@ -424,7 +431,7 @@ function buildMembers(
 
         property: function( name, value, keywords )
         {
-            var dest = ( keywords[ 'static' ] ) ? static_members : prop_init;
+            var dest = ( keywords[ 'static' ] ) ? sprops : prop_init;
 
             // build a new property, passing in the other members to compare
             // against for preventing nonsensical overrides
@@ -435,7 +442,7 @@ function buildMembers(
 
         getter: function( name, value, keywords )
         {
-            var dest = ( keywords[ 'static' ] ) ? static_members : members;
+            var dest = ( keywords[ 'static' ] ) ? smethods : members;
 
             member_builder.buildGetter(
                 dest, null, name, value, keywords
@@ -444,7 +451,7 @@ function buildMembers(
 
         setter: function( name, value, keywords )
         {
-            var dest = ( keywords[ 'static' ] ) ? static_members : members;
+            var dest = ( keywords[ 'static' ] ) ? smethods : members;
 
             member_builder.buildSetter(
                 dest, null, name, value, keywords
@@ -453,7 +460,7 @@ function buildMembers(
 
         method: function( name, func, is_abstract, keywords )
         {
-            var dest = ( keywords[ 'static' ] ) ? static_members : members;
+            var dest = ( keywords[ 'static' ] ) ? smethods : members;
 
             // constructor check
             if ( public_methods[ name ] === true )
@@ -560,24 +567,47 @@ function attachPropInit( prototype, properties, members, cid )
 /**
  * Attaches static members to a constructor (class)
  *
+ * Static methods will be assigned to the constructor itself. Properties, on the
+ * other hand, will be assigned to ctor.$. The reason for this is because JS
+ * engines pre-ES5 support no means of sharing references to primitives. Static
+ * properties of subtypes should share references to the static properties of
+ * their parents.
+ *
  * @param  {function()}  ctor        class
  * @param  {Object}      members     static members
+ * @param  {function()}  base        base class inheriting from
+ * @param  {boolean}     inheriting  true if inheriting static members,
+ *                                   otherwise false (setting own static
+ *                                   members)
  *
  * @return  {undefined}
  */
-function attachStatic( ctor, members, base )
+function attachStatic( ctor, members, base, inheriting )
 {
-    // "inherit" the parent's static members by running the parent's static
+    var methods = members.methods,
+        props   = members.props;
+
+    // "inherit" the parent's static methods by running the parent's static
     // initialization method
     var baseinit = base.___$$sinit$$;
     if ( baseinit )
     {
-        baseinit( ctor );
+        baseinit( ctor, true );
+    }
+
+    // initialize static property if not yet defined
+    if ( !inheriting )
+    {
+        // "inherit" properties from the supertype, if available
+        ctor.$ = base.$ || {};
+
+        // add our own properties
+        util.copyTo( ctor.$, props[ 'public' ], true );
     }
 
     // copy over public static members (deep copy; we don't want subtypes to
     // share references with their parents)
-    util.copyTo( ctor, members[ 'public' ], true );
+    util.copyTo( ctor, methods[ 'public' ], true );
 }
 
 

test/test-class_builder-static.js

@@ -79,13 +79,13 @@ var common    = require( './common' ),
         } );
 
     // properties should be accessible via class definition
-    assert.equal( Foo.foo, val,
+    assert.equal( Foo.$.foo, val,
         "Public static properties should be accessible via class definition"
     );
 
     // as long as the above test succeeded, we can then conclude that static
     // members are public by default if the following succeeds
-    assert.equal( Foo.bar, val2,
+    assert.equal( Foo.$.bar, val2,
         "Static properties are public by default"
     );
 
@@ -240,10 +240,10 @@ var common    = require( './common' ),
     ;
 
     // properties
-    assert.equal( SubFoo.foo, Foo.foo,
+    assert.equal( SubFoo.$.foo, Foo.$.foo,
         "Public static properties are inherited by subtypes"
     );
-    assert.equal( SubSubFoo.foo, Foo.foo,
+    assert.equal( SubSubFoo.$.foo, Foo.$.foo,
         "Public static properties are inherited by sub-subtypes"
     );
 
@@ -256,7 +256,7 @@ var common    = require( './common' ),
     );
 
     // merge
-    assert.equal( SubFoo.baz, baz,
+    assert.equal( SubFoo.$.baz, baz,
         "Subtypes contain both inherited static members as well as their own"
     );
 
@@ -288,10 +288,11 @@ var common    = require( './common' ),
 
 
 /**
- * Each class should have its own set of static values. That is, a subtype
+ * Static references should be inherited by subtypes. That is, modifying a
- * should not share references with its parent.
+ * static property of a supertype should modify the same static property of the
+ * subtype, so long as the subtype has not defined a property of the same name.
  */
-( function testInheritedPublicStaticPropertiesAreClones()
+( function testPublicStaticPropertyReferencesAreInheritedBySubtypes()
 {
     var val = [ 1, 2, 3 ],
         Foo = builder.build(
@@ -301,14 +302,9 @@ var common    = require( './common' ),
         SubFoo = builder.build( Foo, {} )
     ;
 
-    // the values should certainly be equal...
+    // the properties should reference the same object
-    assert.deepEqual( SubFoo.bar, Foo.bar,
+    assert.ok( SubFoo.$.bar === Foo.$.bar,
-        "Inherited static properties should be equal by value"
+        "Inherited static properties should share references"
-    );
-
-    // ...but they should not be the same object
-    assert.ok( SubFoo.bar !== Foo.bar,
-        "Inherited static propertis should not be the same object"
     );
 } )();