Use shallowEqual to fix extraenous setPath() calls.

Fixes #177

Author: STRML

lib/RouterMixin.js

@@ -5,6 +5,7 @@ var invariant     = require('./util/invariant');
 var assign        = Object.assign || require('object-assign');
 var matchRoutes   = require('./matchRoutes');
 var Environment   = require('./environment');
+var shallowEqual  = require('is-equal-shallow');
 
 var RouterMixin = {
   mixins: [Environment.Mixin],
@@ -39,8 +40,10 @@ var RouterMixin = {
   },
 
   componentWillReceiveProps: function(nextProps) {
-    var nextState = this.getRouterState(nextProps);
-    this.delegateSetRoutingState(nextState);
+    if (!shallowEqual(nextProps, this.props)) {
+      var nextState = this.getRouterState(nextProps);
+      this.delegateSetRoutingState(nextState);
+    }
   },
 
   getRouterState: function(props) {

package.json

@@ -4,6 +4,7 @@
   "description": "Declarative router component for React",
   "main": "index.js",
   "dependencies": {
+    "is-equal-shallow": "^0.1.3",
     "object-assign": "^4.1.0",
     "object.omit": "^2.0.0",
     "qs": "^6.2.0",
@@ -70,4 +71,4 @@
   "publishConfig": {
     "registry": "https://registry.npmjs.org"
   }
-}
+}