Fixed #3121 -- Made get_or_create() work for RelatedManager and ManyRelatedManager.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@8415 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/regressiontests/get_or_create_regress/models.py

@@ -0,0 +1,91 @@
+from django.db import models
+
+class Publisher(models.Model):
+    name = models.CharField(max_length=100)
+
+class Author(models.Model):
+    name = models.CharField(max_length=100)
+
+class Book(models.Model):
+    name = models.CharField(max_length=100)
+    authors = models.ManyToManyField(Author, related_name='books')
+    publisher = models.ForeignKey(Publisher, related_name='books')
+
+
+__test__ = {'one':"""
+#
+# RelatedManager
+#
+
+# First create a Publisher.
+>>> p = Publisher.objects.create(name='Acme Publishing')
+
+# Create a book through the publisher.
+>>> book, created = p.books.get_or_create(name='The Book of Ed & Fred')
+>>> created
+True
+
+# The publisher should have one book.
+>>> p.books.count()
+1
+
+# Try get_or_create again, this time nothing should be created.
+>>> book, created = p.books.get_or_create(name='The Book of Ed & Fred')
+>>> created
+False
+
+# And the publisher should still have one book.
+>>> p.books.count()
+1
+
+#
+# ManyRelatedManager
+#
+
+# Add an author to the book.
+>>> ed, created = book.authors.get_or_create(name='Ed')
+>>> created
+True
+
+# Book should have one author.
+>>> book.authors.count()
+1
+
+# Try get_or_create again, this time nothing should be created.
+>>> ed, created = book.authors.get_or_create(name='Ed')
+>>> created
+False
+
+# And the book should still have one author.
+>>> book.authors.count()
+1
+
+# Add a second author to the book.
+>>> fred, created = book.authors.get_or_create(name='Fred')
+>>> created
+True
+
+# The book should have two authors now.
+>>> book.authors.count()
+2
+
+# Create an Author not tied to any books.
+>>> Author.objects.create(name='Ted')
+<Author: Author object>
+
+# There should be three Authors in total. The book object should have two.
+>>> Author.objects.count()
+3
+>>> book.authors.count()
+2
+
+# Try creating a book through an author.
+>>> ed.books.get_or_create(name="Ed's Recipies", publisher=p)
+(<Book: Book object>, True)
+
+# Now Ed has two Books, Fred just one.
+>>> ed.books.count()
+2
+>>> fred.books.count()
+1
+"""}