use id from preloaded gon.post to fix broken liking with guid

closes #5978

Changelog.md

@@ -36,6 +36,7 @@
 * Handle empty searchable in HCard gracefully [#5962](https://github.com/diaspora/diaspora/pull/5962)
 * Fix a freeze in new post parsing [#5965](https://github.com/diaspora/diaspora/pull/5965)
 * Add case insensitive unconfirmed email addresses as authentication key [#5967](https://github.com/diaspora/diaspora/pull/5967)
+* Fix liking on single post views when accessed via GUID [#5978](https://github.com/diaspora/diaspora/pull/5978)
 
 ## Features
 * Hide post title of limited post in comment notification email [#5843](https://github.com/diaspora/diaspora/pull/5843)

app/assets/javascripts/app/pages/single-post-viewer.js

@@ -8,8 +8,8 @@ app.pages.SinglePostViewer = app.views.Base.extend({
     '#single-post-interactions' : 'singlePostInteractionsView'
   },
 
-  initialize : function(options) {
-    this.model = new app.models.Post({ id : options.id });
+  initialize : function() {
+    this.model = new app.models.Post({ id : gon.post.id });
     this.model.preloadOrFetch().done(_.bind(this.initViews, this));
     this.model.interactions.fetch(); //async, yo, might want to throttle this later.
     this.setupLightbox();

spec/javascripts/app/pages/single-post-viewer_spec.js

@@ -0,0 +1,12 @@
+describe("app.pages.SinglePostViewer", function(){
+  beforeEach(function() {
+    window.gon={};gon.post = {id: 42};
+    this.view = new app.pages.SinglePostViewer();
+  });
+
+  context("#initialize", function() {
+    it("uses post-id from gon", function() {
+      expect(this.view.model.id).toBe(gon.post.id);
+    });
+  });
+});