def test_chain_parent_sr():
qs = Chain(NSR('publisher')).rebuild(Chain(
SelectRelated('author'))).apply(default_qs)
assert qs.query.select_related == {'author': {'publisher': {}}}
def test_nsr_apply_sr_parent():
qs = NestedSelectRelated('publisher').rebuild(
SelectRelated('author')).apply(default_qs)
assert qs.query.select_related == {'author': {'publisher': {}}}
def test_chain_without_parent():
qs = Chain(SelectRelated('author__publisher'),
SelectRelated('author')).apply(default_qs)
assert qs.query.select_related == {'author': {'publisher': {}}}
def test_nested_prefetch_object_in_parent():
with pytest.raises(AssertionError) as e:
NestedPrefetchRelated('pages').rebuild(
PrefetchRelated(Prefetch('pages')))
assert str(e.value) == 'Only simple parent relations are supported.'
def test_npr_apply_no_parent():
qs = NestedPrefetchRelated('pages').apply(default_qs)
assert qs._prefetch_related_lookups == ('pages', )
@pytest.mark.parametrize('parent',
(PrefetchRelated('author'), SelectRelated('author')))
def test_npr_apply_parent(parent):
qs = NestedPrefetchRelated('publisher').rebuild(parent).apply(default_qs)
assert qs._prefetch_related_lookups == ('author__publisher', )
def test_npr_apply_multi():
qs = NPR(Prefetch('publisher'),
'publisher').rebuild(SelectRelated('author')).apply(default_qs)
assert len(qs._prefetch_related_lookups) == 2
assert qs._prefetch_related_lookups[1] == 'author__publisher'
pr_obj = qs._prefetch_related_lookups[0]
assert isinstance(pr_obj, Prefetch)
assert pr_obj.prefetch_through == pr_obj.prefetch_to == 'author__publisher'