add comments to ambiguous code

lib/6to5/transformation/modules/umd.js

@@ -31,15 +31,17 @@ UMDFormatter.prototype.transform = function (ast) {
 
   var factory = t.functionExpression(null, args, t.blockStatement(body));
 
-  // runner
+  // amd
 
   var defineArgs = [t.literal("exports")];
   if (this.passModuleArg) defineArgs.push(t.literal("module"));
   defineArgs = defineArgs.concat(names);
   defineArgs = [t.arrayExpression(defineArgs)];
 
+  // common
+
   var testExports = util.template("test-exports");
-  var testModule = util.template("test-module");
+  var testModule  = util.template("test-module");
   var commonTests = this.passModuleArg ? t.logicalExpression("&&", testExports, testModule) : testExports;
 
   var commonArgs = [t.identifier("exports")];
@@ -48,6 +50,12 @@ UMDFormatter.prototype.transform = function (ast) {
     return t.callExpression(t.identifier("require"), [name]);
   }));
 
+  // globals
+
+  var umdArgs = [];
+
+  //
+
   var moduleName = this.getModuleName();
   if (moduleName) defineArgs.unshift(t.literal(moduleName));
 

lib/6to5/transformation/transformers/react.js

@@ -42,6 +42,7 @@ var isTag = function(tagName) {
 
 exports.XJSOpeningElement = {
   exit: function (node, parent, file) {
+    console.log(node);
     var reactCompat = file.opts.reactCompat;
     var tagExpr = node.name;
     var args = [];
@@ -61,11 +62,16 @@ exports.XJSOpeningElement = {
       }
     }
 
-    var props = node.attributes;
-    if (props.length) {
+    var attribs = node.attributes;
+    if (attribs.length) {
       var _props = [];
       var objs = [];
 
+      // so basically in order to support spread elements we
+      // loop over all the attributes, breaking on spreads
+      // we then push a new object containing all prior attributes
+      // to an array for later processing
+
       var pushProps = function () {
         if (!_props.length) return;
 
@@ -73,8 +79,8 @@ exports.XJSOpeningElement = {
         _props = [];
       };
 
-      while (props.length) {
-        var prop = props.shift();
+      while (attribs.length) {
+        var prop = attribs.shift();
         if (t.isXJSSpreadAttribute(prop)) {
           pushProps();
           objs.push(prop.argument);
@@ -86,22 +92,25 @@ exports.XJSOpeningElement = {
       pushProps();
 
       if (objs.length === 1) {
-        props = objs[0];
+        // only one object
+        attribs = objs[0];
       } else {
+        // looks like we have multiple objects
         if (!t.isObjectExpression(objs[0])) {
           objs.unshift(t.objectExpression([]));
         }
 
-        props = t.callExpression(
+        // spread it
+        attribs = t.callExpression(
           t.memberExpression(t.identifier("React"), t.identifier("__spread")),
           objs
         );
       }
     } else {
-      props = t.literal(null);
+      attribs = t.literal(null);
     }
 
-    args.push(props);
+    args.push(attribs);
 
     if (reactCompat) {
       if (tagName && isTag(tagName)) {