Automatically add active params to <Link>s

Added a test stub, but still not sure about our strategy for testing
actual components. Would love for someone with more experience in this
area to help out.

Fixes #89

Author: mjackson

modules/components/Link.js

@@ -1,5 +1,7 @@
 var React = require('react');
 var ActiveState = require('../mixins/ActiveState');
+var ActiveStore = require('../helpers/ActiveStore');
+var mergeProperties = require('../helpers/mergeProperties');
 var withoutProperties = require('../helpers/withoutProperties');
 var transitionTo = require('../helpers/transitionTo');
 var makeHref = require('../helpers/makeHref');
@@ -66,7 +68,8 @@ var Link = React.createClass({
    * Returns a hash of URL parameters to use in this <Link>'s path.
    */
   getParams: function () {
-    return Link.getUnreservedProps(this.props);
+    // Links may omit active params. See #89
+    return mergeProperties(ActiveStore.getActiveParams(), Link.getUnreservedProps(this.props));
   },
 
   /**

modules/stores/ActiveStore.js

@@ -68,6 +68,27 @@ var ActiveStore = {
     notifyChange();
   },
 
+  /**
+   * Returns an array of the currently active routes.
+   */
+  getActiveRoutes: function () {
+    return _activeRoutes;
+  },
+
+  /**
+   * Returns a hash of the currently active params.
+   */
+  getActiveParams: function () {
+    return _activeParams;
+  },
+
+  /**
+   * Returns a hash of the currently active query parameters.
+   */
+  getActiveQuery: function () {
+    return _activeQuery;
+  },
+
   /**
    * Returns true if the route with the given name, URL parameters, and query
    * are all currently active.

specs/Link.spec.js

@@ -0,0 +1,6 @@
+require('./helper');
+var Link = require('../modules/components/Link');
+
+describe('a Link that is present in an active route', function () {
+  it('automatically gets the active params');
+});