warn on invalid packages

lib/package.js

@@ -75,15 +75,23 @@
     if (!pkgConfig.env)
       return Promise.resolve(pkgConfig);
 
+    // NB this derive function will run many times as we have no queue
+
     // check environment conditions
     // default environment condition is '@env' in package or '@system-env' globally
     return loader['import'](pkgConfig.map['@env'] || '@system-env', pkgName)
     .then(function(env) {
       // derived config object
       var pkg = {};
-      for (var p in pkgConfig)
-        if (p !== 'map' & p !== 'env')
+      for (var p in pkgConfig) {
+        if (p == 'main' || p == 'format' || p == 'defaultExtension' || p == 'meta') {
           pkg[p] = pkgConfig[p];
+        }
+        else if (p != 'map' && p != 'env') {
+          if (typeof console != 'undefined' && console.warn)
+            console.warn('"' + p + '" is not a valid package configuration option in package ' + pkgName);
+        }
+      }
 
       pkg.map = {};
       for (var p in pkgConfig.map)
@@ -100,6 +108,7 @@
       }
 
       // store the derived environment config so we have this cached for next time
+      console.log('store derived');
       loader.packages[pkgName] = pkg;
 
       return pkg;

test/test.js

@@ -894,7 +894,8 @@ asyncTest('Package configuration CommonJS config example', function() {
               './env-module': './env-module-browser.js'
             }
           }
-        }
+        },
+        asdf: 'asdf'
       }
     }
   });