1 files changed, 42 insertions, 5 deletions

diff --git a/tests/modeltests/select_related/models.py b/tests/modeltests/select_related/models.py
index f0fd121665..9d64cf24c6 100644
--- a/tests/modeltests/select_related/models.py
+++ b/tests/modeltests/select_related/models.py
@@ -27,13 +27,13 @@ class Phylum(models.Model):
     kingdom = models.ForeignKey(Kingdom)
     def __unicode__(self):
         return self.name
-    
+
 class Klass(models.Model):
     name = models.CharField(max_length=50)
     phylum = models.ForeignKey(Phylum)
     def __unicode__(self):
         return self.name
-    
+
 class Order(models.Model):
     name = models.CharField(max_length=50)
     klass = models.ForeignKey(Klass)
@@ -63,7 +63,7 @@ def create_tree(stringtree):
     names = stringtree.split()
     models = [Domain, Kingdom, Phylum, Klass, Order, Family, Genus, Species]
     assert len(names) == len(models), (names, models)
-    
+
     parent = None
     for name, model in zip(names, models):
         try:
@@ -100,7 +100,7 @@ __test__ = {'API_TESTS':"""
 
 # However, a select_related() call will fill in those related objects without any extra queries:
 >>> db.reset_queries()
->>> person = Species.objects.select_related().get(name="sapiens")
+>>> person = Species.objects.select_related(depth=10).get(name="sapiens")
 >>> person.genus.family.order.klass.phylum.kingdom.domain
 <Domain: Eukaryota>
 >>> len(db.connection.queries)
@@ -129,7 +129,7 @@ __test__ = {'API_TESTS':"""
 >>> pea.genus.family.order.klass.phylum.kingdom.domain
 <Domain: Eukaryota>
 
-# Notice: one few query than above because of depth=1
+# Notice: one fewer queries than above because of depth=1
 >>> len(db.connection.queries)
 7
 
@@ -147,6 +147,43 @@ __test__ = {'API_TESTS':"""
 >>> len(db.connection.queries)
 5
 
+>>> s = Species.objects.all().select_related(depth=1).extra(select={'a': 'select_related_species.id + 10'})[0]
+>>> s.id + 10 == s.a
+True
+
+# The optional fields passed to select_related() control which related models
+# we pull in. This allows for smaller queries and can act as an alternative
+# (or, in addition to) the depth parameter.
+
+# In the next two cases, we explicitly say to select the 'genus' and
+# 'genus.family' models, leading to the same number of queries as before.
+>>> db.reset_queries()
+>>> world = Species.objects.select_related('genus__family')
+>>> [o.genus.family for o in world]
+[<Family: Drosophilidae>, <Family: Hominidae>, <Family: Fabaceae>, <Family: Amanitacae>]
+>>> len(db.connection.queries)
+1
+
+>>> db.reset_queries()
+>>> world = Species.objects.filter(genus__name='Amanita').select_related('genus__family')
+>>> [o.genus.family.order for o in world]
+[<Order: Agaricales>]
+>>> len(db.connection.queries)
+2
+
+>>> db.reset_queries()
+>>> Species.objects.all().select_related('genus__family__order').order_by('id')[0:1].get().genus.family.order.name
+u'Diptera'
+>>> len(db.connection.queries)
+1
+
+# Specifying both "depth" and fields is an error.
+>>> Species.objects.select_related('genus__family__order', depth=4)
+Traceback (most recent call last):
+...
+TypeError: Cannot pass both "depth" and fields to select_related()
+
 # Reset DEBUG to where we found it.
 >>> settings.DEBUG = False
 """}
+