Fix: Module cache did not propagate

This patch makes sure nested modules are available in their parents
cache. The module simplification broke this behavior.

See:

http://groups.google.com/group/nodejs/browse_thread/thread/e875132469547d2
b73f61a137

src/node.js

@@ -48,12 +48,12 @@ function Module (id, parent) {
   this.exports = {};
   this.parent = parent;
 
-  this.moduleCache = {};
-
   if (parent) {
-    process.mixin(this.moduleCache, parent.moduleCache);
-    this.moduleCache[parent.id] = parent;
+    this.moduleCache = parent.moduleCache;
+  } else {
+    this.moduleCache = {};
   }
+  this.moduleCache[this.id] = this;
 
   this.filename = null;
   this.loaded = false;

test/mjsunit/fixtures/a.js

@@ -4,6 +4,7 @@ debug("load fixtures/a.js");
 
 var string = "A";
 
+exports.SomeClass = c.SomeClass;
 
 exports.A = function () {
   return string;

test/mjsunit/fixtures/b/c.js

@@ -10,6 +10,10 @@ debug("load fixtures/b/c.js");
 
 var string = "C";
 
+exports.SomeClass = function() {
+ 
+};
+
 exports.C = function () {
   return string;
 };

test/mjsunit/test-module-loading.js

@@ -3,6 +3,7 @@ process.mixin(require("./common"));
 debug("load test-module-loading.js");
 
 var a = require("./fixtures/a");
+var c = require("./fixtures/b/c");
 var d = require("./fixtures/b/d");
 var d2 = require("./fixtures/b/d");
 // Absolute
@@ -33,6 +34,8 @@ assert.equal("D", d3.D());
 assert.equal(true, d4.D instanceof Function);
 assert.equal("D", d4.D());
 
+assert.ok((new a.SomeClass) instanceof c.SomeClass);
+
 debug("test index.js modules ids and relative loading")
 var one = require("./fixtures/nested-index/one"),
   two = require("./fixtures/nested-index/two");
@@ -41,6 +44,7 @@ assert.notEqual(one.hello, two.hello);
 debug("test cycles containing a .. path");
 var root = require("./fixtures/cycles/root"),
   foo = require("./fixtures/cycles/folder/foo");
+assert.equal(root.foo, foo);
 assert.equal(root.sayHello(), root.hello);
 
 var errorThrown = false;