Merge branch 'replaceState' of https://github.com/lmp/backbone

backbone.js

@@ -700,8 +700,8 @@
     },
 
     // Simple proxy to `Backbone.history` to save a fragment into the history.
-    navigate : function(fragment, triggerRoute) {
-      Backbone.history.navigate(fragment, triggerRoute);
+    navigate : function(fragment, options) {
+      Backbone.history.navigate(fragment, options);
     },
 
     // Bind all defined routes to `Backbone.history`. We have to reverse the
@@ -857,27 +857,54 @@
       return matched;
     },
 
-    // Save a fragment into the hash history. You are responsible for properly
+    // Save a fragment into the hash history, or replace the URL state
+    // if the 'replace' option is passed. You are responsible for properly
     // URL-encoding the fragment in advance. This does not trigger
     // a `hashchange` event.
-    navigate : function(fragment, triggerRoute) {
+    // parameters:
+    //
+    // * fragment: the URL fragment to navigate to (the portion after the '#')
+    // * options: An object with the following parameters:
+    //            - trigger: call the route corresponding to the provided fragment
+    //            - replace: Navigate such that the back button will
+    //              not return to this current state.
+    //
+    //            To comply with earlier API specifications, passing
+    //            true/false for options will be interpretted as
+    //            {options: trigger: true/false}
+    navigate : function(fragment, options) {
+      if (!options || typeof options === 'boolean') options = {trigger: options};
       var frag = (fragment || '').replace(hashStrip, '');
       if (this.fragment == frag || this.fragment == decodeURIComponent(frag)) return;
       if (this._hasPushState) {
-        var loc = window.location;
         if (frag.indexOf(this.options.root) != 0) frag = this.options.root + frag;
         this.fragment = frag;
-        window.history.pushState({}, document.title, loc.protocol + '//' + loc.host + frag);
+        if (options.replace) {
+          window.history.replaceState({}, document.title, frag);
+        } else {
+          window.history.pushState({}, document.title, frag);
+        }
       } else {
-        window.location.hash = this.fragment = frag;
+        this.fragment = frag;
+        this._updateLocationHash(window.location, frag, options.replace);
         if (this.iframe && (frag != this.getFragment(this.iframe.location.hash))) {
-          this.iframe.document.open().close();
-          this.iframe.location.hash = frag;
+          // Opening and closing the iframe tricks IE7 and earlier to push a history entry on hash-tag change.
+          // When replace is true, we don't want this.
+          if(!options.replace) this.iframe.document.open().close();
+          this._updateLocationHash(this.iframe.location, frag, options.replace);
         }
       }
-      if (triggerRoute) this.loadUrl(fragment);
-    }
+      if (options.trigger) this.loadUrl(fragment);
+    },
 
+    // Since you can't run `location.replace` on a hash fragment, this
+    // helper function provides an effective work-around.
+    _updateLocationHash: function(location, new_fragment, replace) {
+      if (replace)
+        location.replace(location.toString().replace(/#.*$/, "") + "#" + new_fragment);
+      else
+        location.hash = new_fragment;
+    }
   });
 
   // Backbone.View