def test_get_page_empty_object_list_and_allow_empty_first_page_false(self):
"""
Paginator.get_page() raises EmptyPage if allow_empty_first_page=False
and object_list is empty.
"""
paginator = Paginator([], 2, allow_empty_first_page=False)
with self.assertRaises(EmptyPage):
paginator.get_page(1)
def test_get_page_empty_object_list(self):
"""Paginator.get_page() with an empty object_list."""
paginator = Paginator([], 2)
# An empty page returns the last page.
self.assertEqual(paginator.get_page(1).number, 1)
self.assertEqual(paginator.get_page(2).number, 1)
# Non-integer page returns the first page.
self.assertEqual(paginator.get_page(None).number, 1)
def test_get_page(self):
"""
Paginator.get_page() returns a valid page even with invalid page
arguments.
"""
paginator = Paginator([1, 2, 3], 2)
page = paginator.get_page(1)
self.assertEqual(page.number, 1)
self.assertEqual(page.object_list, [1, 2])
# An empty page returns the last page.
self.assertEqual(paginator.get_page(3).number, 2)
# Non-integer page returns the first page.
self.assertEqual(paginator.get_page(None).number, 1)
def test_invalid_page_number(self):
"""
Invalid page numbers result in the correct exception being raised.
"""
paginator = Paginator([1, 2, 3], 2)
with self.assertRaises(InvalidPage):
paginator.page(3)
with self.assertRaises(PageNotAnInteger):
paginator.validate_number(None)
with self.assertRaises(PageNotAnInteger):
paginator.validate_number('x')
with self.assertRaises(PageNotAnInteger):
paginator.validate_number(1.2)
def test_last_page(self):
paginator = Paginator(Article.objects.order_by('id'), 5)
p = paginator.page(2)
self.assertEqual("<Page 2 of 2>", str(p))
self.assertQuerysetEqual(p.object_list, [
"<Article: Article 6>", "<Article: Article 7>",
"<Article: Article 8>", "<Article: Article 9>"
])
self.assertFalse(p.has_next())
self.assertTrue(p.has_previous())
self.assertTrue(p.has_other_pages())
with self.assertRaises(InvalidPage):
p.next_page_number()
self.assertEqual(1, p.previous_page_number())
self.assertEqual(6, p.start_index())
self.assertEqual(9, p.end_index())
def test_count_does_not_silence_type_error(self):
class TypeErrorContainer:
def count(self):
raise TypeError('abc')
with self.assertRaisesMessage(TypeError, 'abc'):
Paginator(TypeErrorContainer(), 10).count()
def test_count_does_not_silence_attribute_error(self):
class AttributeErrorContainer:
def count(self):
raise AttributeError('abc')
with self.assertRaisesMessage(AttributeError, 'abc'):
Paginator(AttributeErrorContainer(), 10).count()
def test_paginating_unordered_queryset_raises_warning(self):
msg = ("Pagination may yield inconsistent results with an unordered "
"object_list: <class 'pagination.models.Article'> QuerySet.")
with self.assertWarnsMessage(UnorderedObjectListWarning, msg) as cm:
Paginator(Article.objects.all(), 5)
# The warning points at the Paginator caller (i.e. the stacklevel
# is appropriate).
self.assertEqual(cm.filename, __file__)
def test_page_sequence(self):
"""
A paginator page acts like a standard sequence.
"""
eleven = 'abcdefghijk'
page2 = Paginator(eleven, per_page=5, orphans=1).page(2)
self.assertEqual(len(page2), 6)
self.assertIn('k', page2)
self.assertNotIn('a', page2)
self.assertEqual(''.join(page2), 'fghijk')
self.assertEqual(''.join(reversed(page2)), 'kjihgf')
def test_paginate_misc_classes(self):
class CountContainer:
def count(self):
return 42
# Paginator can be passed other objects with a count() method.
paginator = Paginator(CountContainer(), 10)
self.assertEqual(42, paginator.count)
self.assertEqual(5, paginator.num_pages)
self.assertEqual([1, 2, 3, 4, 5], list(paginator.page_range))
# Paginator can be passed other objects that implement __len__.
class LenContainer:
def __len__(self):
return 42
paginator = Paginator(LenContainer(), 10)
self.assertEqual(42, paginator.count)
self.assertEqual(5, paginator.num_pages)
self.assertEqual([1, 2, 3, 4, 5], list(paginator.page_range))
def check_indexes(self, params, page_num, indexes):
"""
Helper method that instantiates a Paginator object from the passed
params and then checks that the start and end indexes of the passed
page_num match those given as a 2-tuple in indexes.
"""
paginator = Paginator(*params)
if page_num == 'first':
page_num = 1
elif page_num == 'last':
page_num = paginator.num_pages
page = paginator.page(page_num)
start, end = indexes
msg = (
"For %s of page %s, expected %s but got %s. Paginator parameters were: %s"
)
self.assertEqual(
start, page.start_index(),
msg % ('start index', page_num, start, page.start_index(), params))
self.assertEqual(
end, page.end_index(),
msg % ('end index', page_num, end, page.end_index(), params))
def test_paginating_unordered_object_list_raises_warning(self):
"""
Unordered object list warning with an object that has an ordered
attribute but not a model attribute.
"""
class ObjectList:
ordered = False
object_list = ObjectList()
msg = ("Pagination may yield inconsistent results with an unordered "
"object_list: {!r}.".format(object_list))
with self.assertWarnsMessage(UnorderedObjectListWarning, msg):
Paginator(object_list, 5)
def check_paginator(self, params, output):
"""
Helper method that instantiates a Paginator object from the passed
params and then checks that its attributes match the passed output.
"""
count, num_pages, page_range = output
paginator = Paginator(*params)
self.check_attribute('count', paginator, count, params)
self.check_attribute('num_pages', paginator, num_pages, params)
self.check_attribute('page_range',
paginator,
page_range,
params,
coerce=list)
def test_page_getitem(self):
"""
Tests proper behavior of a paginator page __getitem__ (queryset
evaluation, slicing, exception raised).
"""
paginator = Paginator(Article.objects.order_by('id'), 5)
p = paginator.page(1)
# Make sure object_list queryset is not evaluated by an invalid __getitem__ call.
# (this happens from the template engine when using eg: {% page_obj.has_previous %})
self.assertIsNone(p.object_list._result_cache)
with self.assertRaises(TypeError):
p['has_previous']
self.assertIsNone(p.object_list._result_cache)
self.assertNotIsInstance(p.object_list, list)
# Make sure slicing the Page object with numbers and slice objects work.
self.assertEqual(p[0], Article.objects.get(headline='Article 1'))
self.assertQuerysetEqual(p[slice(2)], [
"<Article: Article 1>",
"<Article: Article 2>",
])
# After __getitem__ is called, object_list is a list
self.assertIsInstance(p.object_list, list)
def test_page_range_iterator(self):
"""
Paginator.page_range should be an iterator.
"""
self.assertIsInstance(
Paginator([1, 2, 3], 2).page_range, type(range(0)))
def test_paginating_empty_queryset_does_not_warn(self):
with warnings.catch_warnings(record=True) as recorded:
Paginator(Article.objects.none(), 5)
self.assertEqual(len(recorded), 0)
def test_no_content_allow_empty_first_page(self):
# With no content and allow_empty_first_page=True, 1 is a valid page number
paginator = Paginator([], 2)
self.assertEqual(paginator.validate_number(1), 1)
def test_float_integer_page(self):
paginator = Paginator([1, 2, 3], 2)
self.assertEqual(paginator.validate_number(1.0), 1)
