Fix problem adding photos from photosets.

When we fetched photos from a photoset, the response object didn't
respond to to_a, breaking our controller code. This turned out to be due
to weirdness in FlickRaw's API:
https://github.com/hanklords/flickraw/issues/58

app/controllers/photos_controller.rb

@@ -33,11 +33,10 @@ class PhotosController < ApplicationController
     @flickr_auth = current_member.auth('flickr')
     if @flickr_auth
       @sets = current_member.flickr_sets
-      photos = current_member.flickr_photos(page, params[:set])
-      total = photos.instance_of?(FlickRaw::ResponseList) ? photos.total : 0
+      photos, total = current_member.flickr_photos(page, params[:set])
 
       @photos = WillPaginate::Collection.create(page, 30, total) do |pager|
-        pager.replace photos.to_a
+        pager.replace photos
       end
     end
 

app/models/member.rb

@@ -150,19 +150,37 @@ class Member < ActiveRecord::Base
   end
 
   # Fetches a collection of photos from Flickr
+  # Returns a [[page of photos], total] pair.
+  # Total is needed for pagination.
   def flickr_photos(page_num=1, set=nil)
+    # FlickRaw returns a ResponseList when asked for a user's photos, but a
+    # Response when asked for photos in a set. Only ResponseList supports
+    # to_a(). Both support total(). Hence the following.
+    #
+    # We think this is a bug in FlickRaw, and have reported it here:
+    # https://github.com/hanklords/flickraw/issues/58
     if set
-      return flickr.photosets.getPhotos(
+      result = flickr.photosets.getPhotos(
         :photoset_id => set,
         :page => page_num,
         :per_page => 30
       )
+      if result
+        return [result.photo, result.total]
+      else
+        return [[], 0]
+      end
     else
-      return flickr.people.getPhotos(
+      result_list = flickr.people.getPhotos(
         :user_id => 'me',
         :page => page_num,
         :per_page => 30
       )
+      if result_list
+        return [result_list.to_a, result_list.total]
+      else
+        return [[], 0]
+      end
     end
   end
 

spec/controllers/photos_controller_spec.rb

@@ -23,12 +23,15 @@ describe PhotosController do
   end
 
   describe "GET new" do
-    it "assigns the flickr auth as @flickr_auth" do
+    before(:each) do
       @member = FactoryGirl.create(:member)
       sign_in @member
-      @member.stub(:flickr_photos) { [] }
+      @member.stub(:flickr_photos) { [[], 0] }
       @member.stub(:flickr_sets) { [] }
       controller.stub(:current_member) { @member }
+    end
+
+    it "assigns the flickr auth as @flickr_auth" do
       @auth = FactoryGirl.create(:flickr_authentication, :member => @member)
       get :new, {}
       assigns(:flickr_auth).should be_an_instance_of(Authentication)