From 51e27334cd054dc6fbfc3abf62888812ec58531a Mon Sep 17 00:00:00 2001
From: Mike Gerwitz <mike@mikegerwitz.com>
Date: Sun, 12 Jun 2011 01:07:43 -0400
Subject: [PATCH] Can no longer override methods with getters/setters

---
 lib/member_builder.js                    | 37 +++++++++++++++
 test/test-member_builder-gettersetter.js | 60 ++++++++++++++++++++++--
 2 files changed, 93 insertions(+), 4 deletions(-)

diff --git a/lib/member_builder.js b/lib/member_builder.js
index 7a071c3..cab1729 100644
--- a/lib/member_builder.js
+++ b/lib/member_builder.js
@@ -288,6 +288,8 @@ exports.buildProp = function( members, meta, name, value, keywords, base )
  */
 exports.buildGetter = function( members, meta, name, value, keywords, base )
 {
+    validateGetterSetter( members, keywords, name, base );
+
     Object.defineProperty(
         getMemberVisibility( members, keywords ),
         name,
@@ -320,6 +322,8 @@ exports.buildGetter = function( members, meta, name, value, keywords, base )
  */
 exports.buildSetter = function( members, meta, name, value, keywords, base )
 {
+    validateGetterSetter( members, keywords, name, base );
+
     Object.defineProperty(
         getMemberVisibility( members, keywords ),
         name,
@@ -334,6 +338,39 @@ exports.buildSetter = function( members, meta, name, value, keywords, base )
 };
 
 
+/**
+ * Performs common validations on getters/setters
+ *
+ * If a problem is found, an exception will be thrown.
+ *
+ * @param  {{public: Object, protected: Object, private: Object}} members
+ *
+ * @param  {Object.<string,boolean>}  keywords  parsed keywords
+ * @param  {string}                   name      getter/setter name
+ * @param  {Object}                   base      optional base to parse
+ */
+function validateGetterSetter( members, keywords, name, base )
+{
+    var prev_data = scanMembers( members, name, base ),
+        prev      = ( prev_data ) ? prev_data.member : null,
+
+        prev_keywords = ( prev && prev.___$$keywords$$ )
+            ? prev.___$$keywords$$
+            : {}
+    ;
+
+    if ( prev )
+    {
+        if ( typeof prev === 'function' )
+        {
+            throw TypeError(
+                "Cannot override method '" + name + "' with getter/setter"
+            );
+        }
+    }
+}
+
+
 /**
  * Returns member prototype to use for the requested visibility
  *
diff --git a/test/test-member_builder-gettersetter.js b/test/test-member_builder-gettersetter.js
index 6a3ece8..8d1d966 100644
--- a/test/test-member_builder-gettersetter.js
+++ b/test/test-member_builder-gettersetter.js
@@ -56,15 +56,41 @@ function setUp()
 /**
  * Partially applied function to quickly build getter from common test data
  */
-function buildGetterSetterQuick( keywords, val )
+function buildGetterSetterQuick( keywords, val, preserve_prior, use )
 {
+    preserve_prior = !!preserve_prior;
+    use            = ( use === undefined ) ? 0 : +use;
+
     keywords = keywords || {};
     val      = val || value;
 
-    setUp();
+    if ( !preserve_prior )
+    {
+        setUp();
+    }
 
-    buildGetter( members, meta, name, val, keywords );
-    buildSetter( members, meta, name, val, keywords );
+    if ( use == 0 || use == 1 )
+    {
+        buildGetter( members, meta, name, val, keywords );
+    }
+    if ( use == 0 || use == 2 )
+    {
+        buildSetter( members, meta, name, val, keywords );
+    }
+}
+
+
+function testEach( test )
+{
+    test( 'getter', function( keywords, val, preserve )
+    {
+        buildGetterSetterQuick.call( this, keywords, val, preserve, 1 );
+    } );
+
+    test( 'setter', function( keywords, val, preserve )
+    {
+        buildGetterSetterQuick.call( this, keywords, val, preserve, 2 );
+    } );
 }
 
 
@@ -176,3 +202,29 @@ function assertOnlyVisibility( vis, name, value, message )
 
 } )();
 
+
+/**
+ * Getters/setters should not be able to override methods, for the obvious
+ * reason that they are two different types and operate entirely differently. Go
+ * figure.
+ */
+testEach( function testCannotOverrideMethodWithGetterOrSetter( type, build )
+{
+    setUp();
+
+    // method
+    members[ 'public' ][ name ] = function() {};
+
+    try
+    {
+        // attempt to override method with getter/setter (should fail)
+        build( { 'public': true }, null, true );
+    }
+    catch ( e )
+    {
+        return;
+    }
+
+    assert.fail( type + " should not be able to override methods");
+} );
+