add classProps declaration to simplify/nicen up class property defining - closes #88

lib/6to5/templates/class-props.js

@@ -0,0 +1,4 @@
+(function (child, staticProps, instanceProps) {
+  if (staticProps) Object.defineProperties(child, staticProps);
+  if (instanceProps) Object.defineProperties(child.prototype, instanceProps);
+})

lib/6to5/transformers/classes.js

@@ -56,14 +56,14 @@ var buildClass = function (node, file) {
     container.callee.params.push(superClassCallee);
   }
 
-  buildClassBody(body, className, superName, node);
+  buildClassBody(file, body, className, superName, node);
 
   body.push(returnStatement);
 
   return container;
 };
 
-var buildClassBody = function (body, className, superName, node) {
+var buildClassBody = function (file, body, className, superName, node) {
   var instanceMutatorMap = {};
   var staticMutatorMap   = {};
   var hasConstructor     = false;
@@ -105,16 +105,28 @@ var buildClassBody = function (body, className, superName, node) {
     }, true));
   }
 
+  var instanceProps;
+  var staticProps;
+
   if (!_.isEmpty(instanceMutatorMap)) {
     var protoId = util.template("prototype-identifier", {
       CLASS_NAME: className
     });
 
-    body.push(util.buildDefineProperties(instanceMutatorMap, protoId));
+    instanceProps = util.buildDefineProperties(instanceMutatorMap, protoId);
   }
 
   if (!_.isEmpty(staticMutatorMap)) {
-    body.push(util.buildDefineProperties(staticMutatorMap, className));
+    staticProps = util.buildDefineProperties(staticMutatorMap, className);
+  }
+
+  if (instanceProps || staticProps) {
+    instanceProps = instanceProps || b.literal(null);
+    staticProps = staticProps || b.literal(null);
+
+    body.push(b.expressionStatement(
+      b.callExpression(file.addDeclaration("class-props"), [className, staticProps, instanceProps])
+    ));
   }
 };
 

lib/6to5/transformers/property-method-assignment.js

@@ -24,6 +24,9 @@ exports.ObjectExpression = function (node, parent, file) {
   return util.template("object-define-properties-closure", {
     KEY: objId,
     OBJECT: node,
-    CONTENT: util.buildDefineProperties(mutatorMap, objId).expression
+    CONTENT: util.template("object-define-properties", {
+      OBJECT: objId,
+      PROPS:  util.buildDefineProperties(mutatorMap)
+    })
   });
 };

lib/6to5/util.js

@@ -147,7 +147,7 @@ exports.pushMutatorMap = function (mutatorMap, key, kind, method) {
   }
 };
 
-exports.buildDefineProperties = function (mutatorMap, keyNode) {
+exports.buildDefineProperties = function (mutatorMap) {
   var objExpr = b.objectExpression([]);
 
   _.each(mutatorMap, function (map, key) {
@@ -164,10 +164,7 @@ exports.buildDefineProperties = function (mutatorMap, keyNode) {
     objExpr.properties.push(propNode);
   });
 
-  return exports.template("object-define-properties", {
-    OBJECT: keyNode,
-    PROPS: objExpr
-  }, true);
+  return objExpr;
 };
 
 exports.template = function (name, nodes, keepExpression) {