fix issue #3671 reshare a post multiple times

app/assets/javascripts/app/models/post/interactions.js

@@ -95,14 +95,20 @@ app.models.Post.Interactions = Backbone.Model.extend({
   reshare : function(){
     var interactions = this
       , reshare = this.post.reshare()
+      , flash = new Diaspora.Widgets.FlashMessages;
 
     reshare.save({}, {
       success : function(resp){
-        var flash = new Diaspora.Widgets.FlashMessages;
         flash.render({
           success: true,
           notice: Diaspora.I18n.t("reshares.successful")
         });
+      },
+      error: function(resp){
+        flash.render({
+          success: false,
+          notice: Diaspora.I18n.t("reshares.duplicate")
+        });
       }
     }).done(function(){
         interactions.reshares.add(reshare)
@@ -119,7 +125,8 @@ app.models.Post.Interactions = Backbone.Model.extend({
       , publicPost = this.post.get("public")
       , userIsNotAuthor = this.post.get("author").diaspora_id != app.currentUser.get("diaspora_id")
       , userIsNotRootAuthor = rootExists && (isReshare ? this.post.get("root").author.diaspora_id != app.currentUser.get("diaspora_id") : true)
+      , notReshared = this.reshares.length === 0;
 
-    return publicPost && app.currentUser.authenticated() && userIsNotAuthor && userIsNotRootAuthor;
+    return publicPost && app.currentUser.authenticated() && userIsNotAuthor && userIsNotRootAuthor && notReshared;
   }
 });

app/controllers/reshares_controller.rb

@@ -7,8 +7,9 @@ class ResharesController < ApplicationController
     if @reshare.save
       current_user.add_to_streams(@reshare, current_user.aspects)
       current_user.dispatch_post(@reshare, :url => post_url(@reshare), :additional_subscribers => @reshare.root_author)
-    end
-
       render :json => ExtremePostPresenter.new(@reshare, current_user), :status => 201
+    else
+      render :nothing => true, :status => 422
+    end
   end
 end

features/reshare.feature

@@ -22,3 +22,4 @@ Feature: public repost
     And I wait for the ajax to finish
     Then I should see a flash message indicating success
     And I should see a flash message containing "successfully"
+    And I should not see a ".reshare" within ".feedback"

spec/controllers/reshares_controller_spec.rb

@@ -7,7 +7,8 @@ describe ResharesController do
     }
 
     before do
-      @post_guid = FactoryGirl.create(:status_message, :public => true).guid
+      @post = FactoryGirl.create(:status_message, :public => true)
+      @post_guid = @post.guid
     end
 
     it 'requires authentication' do
@@ -41,6 +42,18 @@ describe ResharesController do
         bob.should_receive(:dispatch_post).with(anything, hash_including(:additional_subscribers))
         post_request!
       end
+
+      context 'resharing a reshared post' do
+        before do
+          FactoryGirl.create(:reshare, :root => @post, :author => bob.person)
+        end
+
+        it 'doesn\'t allow the user to reshare the post again' do
+          post_request!
+          response.code.should == '422'
+          response.body.strip.should be_empty
+        end
+      end
     end
   end
 end