Fixed django#10890: added prev/next_week in the context

of per-week date-based generic views. Thanks ee_lars for the report.

Author: aaugustin

django/views/generic/dates.py

@@ -69,15 +69,15 @@ def get_next_month(self, date):
  next = date.replace(year=date.year + 1, month=1, day=1)
  else:
  next = date.replace(month=date.month + 1, day=1)
- return _get_next_prev_month(self, next, is_previous=False, use_first_day=True)
+ return _get_next_prev(self, next, is_previous=False, period='month')
 
  def get_previous_month(self, date):
  """
  Get the previous valid month.
  """
  # prev must be the last day of the previous month.
  prev = date.replace(day=1) - datetime.timedelta(days=1)
- return _get_next_prev_month(self, prev, is_previous=True, use_first_day=True)
+ return _get_next_prev(self, prev, is_previous=True, period='month')
 
 
 class DayMixin(object):
@@ -109,14 +109,14 @@ def get_next_day(self, date):
  Get the next valid day.
  """
  next = date + datetime.timedelta(days=1)
- return _get_next_prev_month(self, next, is_previous=False, use_first_day=False)
+ return _get_next_prev(self, next, is_previous=False, period='day')
 
  def get_previous_day(self, date):
  """
  Get the previous valid day.
  """
  prev = date - datetime.timedelta(days=1)
- return _get_next_prev_month(self, prev, is_previous=True, use_first_day=False)
+ return _get_next_prev(self, prev, is_previous=True, period='day')
 
 
 class WeekMixin(object):
@@ -143,6 +143,30 @@ def get_week(self):
  raise Http404(_(u"No week specified"))
  return week
 
+ def get_next_week(self, date):
+ """
+ Get the next valid week.
+ """
+ # next must be the first day of the next week.
+ next = date + datetime.timedelta(days=7 - self._get_weekday(date))
+ return _get_next_prev(self, next, is_previous=False, period='week')
+
+ def get_previous_week(self, date):
+ """
+ Get the previous valid week.
+ """
+ # prev must be the last day of the previous week.
+ prev = date - datetime.timedelta(days=self._get_weekday(date) + 1)
+ return _get_next_prev(self, prev, is_previous=True, period='week')
+
+ def _get_weekday(self, date):
+ week_format = self.get_week_format()
+ if week_format == '%W': # week starts on Monday
+ return date.weekday()
+ elif week_format == '%U': # week starts on Sunday
+ return (date.weekday() + 1) % 7
+ else:
+ raise ValueError("unknown week format: %s" % week_format)
 
 class DateMixin(object):
  """
@@ -428,7 +452,11 @@ def get_dated_items(self):
 
  qs = self.get_dated_queryset(**lookup_kwargs)
 
- return (None, qs, {'week': date})
+ return (None, qs, {
+ 'week': date,
+ 'next_week': self.get_next_week(date),
+ 'previous_week': self.get_previous_week(date),
+ })
 
 
 class WeekArchiveView(MultipleObjectTemplateResponseMixin, BaseWeekArchiveView):
@@ -557,7 +585,7 @@ def _date_from_string(year, year_format, month='', month_format='', day='', day_
  })
 
 
-def _get_next_prev_month(generic_view, naive_result, is_previous, use_first_day):
+def _get_next_prev(generic_view, naive_result, is_previous, period):
  """
  Helper: Get the next or the previous valid date. The idea is to allow
  links on month/day views to never be 404s by never providing a date
@@ -620,10 +648,15 @@ def _get_next_prev_month(generic_view, naive_result, is_previous, use_first_day)
  result = timezone.localtime(result)
  result = result.date()
 
- # For month views, we always want to have a date that's the first of the
- # month for consistency's sake.
- if result and use_first_day:
- result = result.replace(day=1)
+ if result:
+ if period == 'month':
+ # first day of the month
+ result = result.replace(day=1)
+ elif period == 'week':
+ # monday of the week
+ result = result - datetime.timedelta(days=generic_view._get_weekday(result))
+ elif period != 'day':
+ raise ValueError('invalid period: %s' % period)
 
  # Check against future dates.
  if result and (allow_future or result < datetime.date.today()):

tests/regressiontests/generic_views/dates.py

@@ -196,7 +196,7 @@ def test_month_view_allow_empty(self):
  self.assertEqual(list(res.context['book_list']), [])
  self.assertEqual(res.context['month'], datetime.date(2000, 1, 1))
 
- # Since it's allow empty, next/prev are allowed to be empty months (#7164)
+ # Since allow_empty=True, next/prev are allowed to be empty months (#7164)
  self.assertEqual(res.context['next_month'], datetime.date(2000, 2, 1))
  self.assertEqual(res.context['previous_month'], datetime.date(1999, 12, 1))
 
@@ -222,7 +222,7 @@ def test_month_view_allow_future(self):
  self.assertEqual(list(res.context['book_list']), [b])
  self.assertEqual(res.context['month'], future)
 
- # Since it's allow_future but not allow_empty, next/prev are not
+ # Since allow_future = True but not allow_empty, next/prev are not
  # allowed to be empty months (#7164)
  self.assertEqual(res.context['next_month'], None)
  self.assertEqual(res.context['previous_month'], datetime.date(2008, 10, 1))
@@ -298,17 +298,35 @@ def test_week_view(self):
  self.assertEqual(res.context['book_list'][0], Book.objects.get(pubdate=datetime.date(2008, 10, 1)))
  self.assertEqual(res.context['week'], datetime.date(2008, 9, 28))
 
+ # Since allow_empty=False, next/prev weeks must be valid
+ self.assertEqual(res.context['next_week'], None)
+ self.assertEqual(res.context['previous_week'], datetime.date(2006, 4, 30))
+
  def test_week_view_allow_empty(self):
+ # allow_empty = False, empty week
  res = self.client.get('/dates/books/2008/week/12/')
  self.assertEqual(res.status_code, 404)
 
+ # allow_empty = True, empty month
  res = self.client.get('/dates/books/2008/week/12/allow_empty/')
  self.assertEqual(res.status_code, 200)
  self.assertEqual(list(res.context['book_list']), [])
+ self.assertEqual(res.context['week'], datetime.date(2008, 3, 23))
+
+ # Since allow_empty=True, next/prev are allowed to be empty weeks
+ self.assertEqual(res.context['next_week'], datetime.date(2008, 3, 30))
+ self.assertEqual(res.context['previous_week'], datetime.date(2008, 3, 16))
+
+ # allow_empty but not allow_future: next_week should be empty
+ url = datetime.date.today().strftime('/dates/books/%Y/week/%U/allow_empty/').lower()
+ res = self.client.get(url)
+ self.assertEqual(res.status_code, 200)
+ self.assertEqual(res.context['next_week'], None)
 
  def test_week_view_allow_future(self):
  # January 7th always falls in week 1, given Python's definition of week numbers
  future = datetime.date(datetime.date.today().year + 1, 1, 7)
+ future_sunday = future - datetime.timedelta(days=(future.weekday() + 1) % 7)
  b = Book.objects.create(name="The New New Testement", pages=600, pubdate=future)
 
  res = self.client.get('/dates/books/%s/week/1/' % future.year)
@@ -317,6 +335,19 @@ def test_week_view_allow_future(self):
  res = self.client.get('/dates/books/%s/week/1/allow_future/' % future.year)
  self.assertEqual(res.status_code, 200)
  self.assertEqual(list(res.context['book_list']), [b])
+ self.assertEqual(res.context['week'], future_sunday)
+
+ # Since allow_future = True but not allow_empty, next/prev are not
+ # allowed to be empty weeks
+ self.assertEqual(res.context['next_week'], None)
+ self.assertEqual(res.context['previous_week'], datetime.date(2008, 9, 28))
+
+ # allow_future, but not allow_empty, with a current week. So next
+ # should be in the future
+ res = self.client.get('/dates/books/2008/week/39/allow_future/')
+ self.assertEqual(res.status_code, 200)
+ self.assertEqual(res.context['next_week'], future_sunday)
+ self.assertEqual(res.context['previous_week'], datetime.date(2006, 4, 30))
 
  def test_week_view_paginated(self):
  week_start = datetime.date(2008, 9, 28)