This fixes failing tests when the timezone is different than utc

There were several problems:
* Time.now returns the systems time, not the users time
* fixtures do not translate dates from timezone to utc, but stores the
  date verbatim
* calling a controller will set the timezone to the preference of the
  current_user. So it could be changed while you do not realize this. I
  fixed the failing test, but problems could be elsewhere

app/controllers/todos_controller.rb

@@ -1071,10 +1071,10 @@ end
       if recurring_todo.todos.active.count == 0
 
         # check for next todo either from the due date or the show_from date
-        date_to_check = todo.due.nil? ? todo.show_from : todo.due
+        date_to_check = todo.due || todo.show_from
 
         # if both due and show_from are nil, check for a next todo from now
-        date_to_check = Time.zone.now if date_to_check.nil?
+        date_to_check ||= Time.zone.now
 
         if recurring_todo.active? && recurring_todo.continues_recurring?(date_to_check)
 
@@ -1087,7 +1087,7 @@ end
           # for tomorrow.
           date = date_to_check.at_midnight >= Time.zone.now.at_midnight ? date_to_check : Time.zone.now-1.day
 
-          new_recurring_todo = TodoFromRecurringTodo.new(current_user, recurring_todo).create(date.at_midnight)
+          new_recurring_todo = TodoFromRecurringTodo.new(current_user, recurring_todo).create(date)
         end
       end
     end

app/helpers/stats_helper.rb

@@ -5,7 +5,7 @@ module StatsHelper
   end
 
   def month_and_year_label(i)
-    t('date.month_names')[ (Time.now.mon - i -1 ) % 12 + 1 ]+ " " + (Time.now - i.months).year.to_s
+    t('date.month_names')[ (Time.zone.now.mon - i -1 ) % 12 + 1 ]+ " " + (Time.zone.now - i.months).year.to_s
   end
 
   def array_of_month_and_year_labels(count)
@@ -13,7 +13,7 @@ module StatsHelper
   end
 
   def month_label(i)
-    t('date.month_names')[ (Time.now.mon - i -1 ) % 12 + 1 ]
+    t('date.month_names')[ (Time.zone.now.mon - i -1 ) % 12 + 1 ]
   end
 
   def array_of_month_labels(count)

app/models/recurring_todos/abstract_recurrence_pattern.rb

@@ -151,7 +151,7 @@ module RecurringTodos
     end
 
     def get_next_date(previous)
-      raise "Should not call AbstractRecurrencePattern.get_next_date directly. Overwrite in subclass"
+      raise "Should not call AbstractRecurrencePattern.get_next_date directly. Override in subclass"
     end
 
     def continues_recurring?(previous)
@@ -174,13 +174,13 @@ module RecurringTodos
     # same day as the previous
     def determine_start(previous, offset=0.day)
       start = self.start_from || NullTime.new
-      now = Time.zone.now
       if previous
         # check if the start_from date is later than previous. If so, use
         # start_from as start to search for next date
         start > previous ? start : previous + offset
       else
         # skip to present
+        now = Time.zone.now
         start > now ? start : now
       end
     end
@@ -199,32 +199,24 @@ module RecurringTodos
     end
 
     def find_last_day_x_of_month(weekday, month, year)
-      # count backwards. use UTC to avoid strange timezone oddities
-      # where last_day -= 1.day seems to shift tz+0100 to tz+0000
-      last_day = Time.utc(year, month, Time.days_in_month(month))
+      last_day = Time.zone.local(year, month, Time.days_in_month(month))
       while last_day.wday != weekday
         last_day -= 1.day
       end
-      # convert back to local timezone
-      Time.zone.local(last_day.year, last_day.month, last_day.day)
+      last_day
     end
 
     def find_xth_day_of_month(x, weekday, month, year)
-      # 1-4th -> count upwards last -> count backwards. use UTC to avoid strange
-      # timezone oddities where last_day -= 1.day seems to shift tz+0100 to
-      # tz+0000
-      start = Time.utc(year,month,1)
+      start = Time.zone.local(year,month,1)
       n = x
       while n > 0
         while start.wday() != weekday
-          start+= 1.day
+          start += 1.day
         end
         n -= 1
-        start+= 1.day unless n==0
+        start += 1.day unless n==0
       end
-      # convert back to local timezone
-      Time.zone.local(start.year, start.month, start.day)
+      start
     end
-
   end
 end

app/models/recurring_todos/monthly_recurrence_pattern.rb

@@ -82,18 +82,9 @@ module RecurringTodos
     def find_specific_day_of_month(previous, start, n)
       if (previous && start.mday >= every_x_day) || (previous.nil? && start.mday > every_x_day)
         # there is no next day n in this month, search in next month
-        #
-        #  start += n.months
-        #
-        # The above seems to not work. Fiddle with timezone. Looks like we hit a
-        # bug in rails here where 2008-12-01 +0100 plus 1.month becomes
-        # 2008-12-31 +0100. For now, just calculate in UTC and convert back to
-        # local timezone.
-        #
-        #  TODO: recheck if future rails versions have this problem too
-        start = Time.utc(start.year, start.month, start.day)+n.months
+        start += n.months
       end
-      Time.zone.local(start.year, start.month, every_x_day)
+      start.in_time_zone.change(day: every_x_day)
     end
 
     def find_relative_day_of_month(start, n)
@@ -101,13 +92,7 @@ module RecurringTodos
       if the_next.nil? || the_next <= start
         # the nth day is already passed in this month, go to next month and try
         # again
-
-        # fiddle with timezone. Looks like we hit a bug in rails here where
-        # 2008-12-01 +0100 plus 1.month becomes 2008-12-31 +0100. For now, just
-        # calculate in UTC and convert back to local timezone.
-        #  TODO: recheck if future rails versions have this problem too
-        the_next = Time.utc(the_next.year, the_next.month, the_next.day)+n.months
-        the_next = Time.zone.local(the_next.year, the_next.month, the_next.day)
+        the_next += n.months
 
         # TODO: if there is still no match, start will be set to nil. if we ever
         # support 5th day of the month, we need to handle this case
@@ -136,7 +121,5 @@ module RecurringTodos
         day:      day_of_week_as_text(day_of_week),
         n_months: n_months)
     end
-
   end
-
 end

app/models/stats/totals.rb

@@ -19,7 +19,7 @@ module Stats
     end
 
     def first_action_at
-      first_action.created_at if first_action
+      first_action.try(:created_at)
     end
 
     def projects

app/views/layouts/application.html.erb

@@ -40,7 +40,7 @@
           <% if @count -%>
             <span id="badge_count" class="badge"><%= @count %></span>
           <% end -%>
-          <%= l(Date.today, :format => current_user.prefs.title_date_format) %>
+          <%= l(Time.zone.today, :format => current_user.prefs.title_date_format) %>
         </h1>
       </div>
       <div id="minilinks">

app/views/layouts/mobile.m.erb

@@ -16,7 +16,7 @@
 </head><body>
 <% if current_user && !current_user.prefs.nil? -%>
 <div id="topbar"><h1><% if @down_count -%><span class="count" id="badge_count"><%= @down_count %></span><% end -%> <%=
-        l(Date.today, :format => current_user.prefs.title_date_format) -%></h1>
+        l(Time.zone.today, :format => current_user.prefs.title_date_format) -%></h1>
 <ul class="nav">
   <li class="link"><%=     (link_to(t('layouts.mobile_navigation.new_action'), new_todo_path(new_todo_params))) -%></li>
   <li class="link"><%=     (link_to(t('layouts.mobile_navigation.home'), todos_path(:format => 'm'))) -%></li>

app/views/preferences/_date_and_time.html.erb

@@ -1,23 +1,22 @@
 <%= pref_with_text_field('prefs', 'date_format') %>
 
-<div class='prefs_example'>This will result in: <span id='prefs.date_format'><%= l(Date.today, :format => current_user.prefs.date_format) %></span></div>
+<div class='prefs_example'>This will result in: <span id='prefs.date_format'><%= l(Time.zone.today, :format => current_user.prefs.date_format) %></span></div>
 <br/>
 Or pick one of the following:<br/>
 <% %w{default short long longer}.each do |format| %>
-<%= radio_button_tag("date_picker1", t("date.formats.#{format}")) %> <%= l(Date.today, :format => format.to_sym) %> <br/>
+<%= radio_button_tag("date_picker1", t("date.formats.#{format}")) %> <%= l(Time.zone.today, :format => format.to_sym) %> <br/>
 <% end %>
 <br/>
 
 <%= pref_with_text_field('prefs', 'title_date_format') %>
-<div class='prefs_example'>This will result in: <span id='prefs.title_date_format'><%= l(Date.today, :format => current_user.prefs.title_date_format) %></span></div>
+<div class='prefs_example'>This will result in: <span id='prefs.title_date_format'><%= l(Time.zone.today, :format => current_user.prefs.title_date_format) %></span></div>
 <br/>
 Or pick one of the following:<br/>
 <% %w{default short long longer}.each do |format| %>
-<%= radio_button_tag("date_picker2", t("date.formats.#{format}")) %> <%= l(Date.today, :format => format.to_sym) %> <br/>
+<%= radio_button_tag("date_picker2", t("date.formats.#{format}")) %> <%= l(Time.zone.today, :format => format.to_sym) %> <br/>
 <% end %>
 <br/>
 
 <%= pref('prefs', 'time_zone') { time_zone_select('prefs','time_zone') } %>
 
 <%= pref_with_select_field('prefs', "week_starts", (0..6).to_a.map {|num| [t('date.day_names')[num], num] }) %>
-