Ticket #251: and_or_clauses.r434.patch

django/core/meta/__init__.py

@@ -1447 +1447 @@
                     except ObjectDoesNotExist:
                         pass
 
-            for f in rel_opts.fields:
+            core_fields = [f for f in rel_opts.fields if f.core]
+            for f in core_fields:
                 if f.core and not isinstance(f, FileField) and f.get_manipulator_new_data(rel_new_data, rel=True) in (None, ''):
                     all_cores_given = False
                 elif f.core and not isinstance(f, FileField) and f.get_manipulator_new_data(rel_new_data, rel=True) not in (None, ''):
@@ -1504 +1505 @@
 
             # If, in the change stage, all of the core fields were blank and
             # the primary key (ID) was provided, delete the item.
-            if change and all_cores_blank and rel_new_data.has_key(rel_opts.pk.name) and rel_new_data[rel_opts.pk.name][0]:
+            if change and all_cores_blank and core_fields and rel_new_data.has_key(rel_opts.pk.name) and rel_new_data[rel_opts.pk.name][0]:
                 new_rel_obj.delete()
                 self.fields_deleted.append('%s "%r"' % (rel_opts.verbose_name, old_rel_obj))
 

tests/testapp/models/__init__.py

@@ -1 +1 @@
 __all__ = ['basic', 'repr', 'custom_methods', 'many_to_one', 'many_to_many',
            'ordering', 'lookup', 'get_latest', 'm2m_intermediary', 'one_to_one',
-           'm2o_recursive', 'm2o_recursive2', 'save_delete_hooks']
+           'm2o_recursive', 'm2o_recursive2', 'save_delete_hooks', 'complex']

tests/testapp/models/complex.py

@@ +1 @@
+"""
+14. Building complex queries.
+
+To build complex queries involving AND and OR clauses, use the meta.AND
+and meta.OR functions.
+"""
+
+from django.core import meta
+
+class Person(meta.Model):
+    fields = (
+        meta.CharField('fname', maxlength=25),
+        meta.CharField('lname', maxlength=25),
+        meta.IntegerField('age'),
+    )
+    def __repr__(self):
+        return '%s %s (%s)' % (self.fname, self.lname, self.age)
+
+API_TESTS = """
+# Make sure meta gets imported; we'll need it later
+>>> from django.core import meta
+
+# Add some people to the system
+>>> p = persons.Person(fname='John', lname='Smith', age=26)
+>>> p.save()
+>>> p = persons.Person(fname='Mary', lname='Smith', age=31)
+>>> p.save()
+>>> p = persons.Person(fname='Betty', lname='Jones', age=30)
+>>> p.save()
+>>> p = persons.Person(fname='Bob', lname='Jones', age=42)
+>>> p.save()
+>>> p = persons.Person(fname='Susan', lname='White', age=70)
+>>> p.save()
+>>> p = persons.Person(fname='James', lname='White', age=65)
+>>> p.save()
+>>> p = persons.Person(fname='Karen', lname='White', age=33)
+>>> p.save()
+
+# Verify that the test data got loaded correctly.
+>>> persons.get_list(order_by=['age'])
+[John Smith (26), Betty Jones (30), Mary Smith (31), Karen White (33), \
+Bob Jones (42), James White (65), Susan White (70)]
+
+# Search clauses are joined with an AND by default
+>>> persons.get_list(order_by=['age'], lname__exact='Smith')
+[John Smith (26), Mary Smith (31)]
+>>> persons.get_list(order_by=['age'], lname__exact='Smith', age__gte=30)
+[Mary Smith (31)]
+
+# Use "clause=meta.OR" to join with an OR instead
+>>> persons.get_list(order_by=['age'], clause=meta.OR(lname__exact='Smith', age__gte=50))
+[John Smith (26), Mary Smith (31), James White (65), Susan White (70)]
+
+# You can nest AND clauses inside OR clauses
+>>> persons.get_list(order_by=['age'], clause=meta.OR(lname__exact='Smith', 
+...     clause=meta.AND(lname__exact='White', age__lte=65)))
+[John Smith (26), Mary Smith (31), Karen White (33), James White (65)]
+
+# Since Python doesn't let you repeat the same keyword parameter twice in a
+# function call, use clause# (where # is a number) if you want to have
+# multiple AND or OR clauses in a single get_list
+# (Remember that the outer level of clauses is joined by AND)
+>>> persons.get_list(order_by=['age'], clause1=meta.OR(age__lte=30, age__gte=60),
+...     clause2=meta.OR(fname__startswith='B', lname__startswith='W'))
+[Betty Jones (30), James White (65), Susan White (70)]
+"""