Merge pull request #30 from mariocasciaro/fix-loop

Prevent infinite loops when state is updated before the actual history change is fired

Author: jlongster

src/index.js

@@ -37,6 +37,7 @@ function locationToString(location) {
 }
 
 function syncReduxAndRouter(history, store, selectRouterState = SELECT_STATE) {
+  let lastRoute;
   const getRouterState = () => selectRouterState(store.getState());
 
   if(!getRouterState()) {
@@ -47,22 +48,26 @@ function syncReduxAndRouter(history, store, selectRouterState = SELECT_STATE) {
   }
 
   const unsubscribeHistory = history.listen(location => {
+    const newLocation = locationToString(location);
     // Avoid dispatching an action if the store is already up-to-date,
     // even if `history` wouldn't do anything if the location is the same
-    if(getRouterState().path !== locationToString(location)) {
-      store.dispatch(updatePath(locationToString(location)));
+    if(getRouterState().path !== newLocation) {
+      lastRoute = newLocation;
+      store.dispatch(updatePath(newLocation));
     }
   });
 
   const unsubscribeStore = store.subscribe(() => {
     const routing = getRouterState();
 
-    // Don't update the router if nothing has changed. The
-    // `noRouterUpdate` flag can be set to avoid updating altogether,
+    // Don't update the router if the routing state hasn't changed or the new routing path
+    // is already the current location.
+    // The `noRouterUpdate` flag can be set to avoid updating altogether,
     // which is useful for things like loading snapshots or very special
     // edge cases.
-    if(routing.path !== locationToString(window.location) &&
+    if(lastRoute !== routing.path && routing.path !== locationToString(window.location) &&
        !routing.noRouterUpdate) {
+      lastRoute = routing.path;
       history.pushState(null, routing.path);
     }
   });
@@ -77,5 +82,5 @@ module.exports = {
   UPDATE_PATH,
   updatePath,
   syncReduxAndRouter,
-  routeReducer: update,
+  routeReducer: update
 };