Always set last_fetched_at in NotesFinder spec

spec/finders/notes_finder_spec.rb

@@ -12,25 +12,25 @@ describe NotesFinder do
   end
 
   describe :execute do
+    let(:params)  { { target_id: commit.id, target_type: 'commit', last_fetched_at: 1.hour.ago } }
+
     before do
       note1
       note2
     end
 
     it 'should find all notes' do
-      params = { target_id: commit.id, target_type: 'commit' }
       notes = NotesFinder.new.execute(project, user, params)
       notes.size.should eq(2)
     end
 
     it 'should raise an exception for an invalid target_type' do
-      params = { target_id: commit.id, target_type: 'invalid' }
+      params.merge!(target_type: 'invalid')
       expect { NotesFinder.new.execute(project, user, params) }.to raise_error('invalid target_type')
     end
 
     it 'filters out old notes' do
       note2.update_attribute(:updated_at, 2.hours.ago)
-      params = { target_id: commit.id, target_type: 'commit', last_fetched_at: 1.hour.ago }
       notes = NotesFinder.new.execute(project, user, params)
       notes.should eq([note1])
     end