Changeset 2260

Timestamp:

02/03/06 18:07:03 (3 years ago)

Author:

adrian

Message:

magic-removal: Added support for QuerySet?.latest() and Manager.latest(), and updated unit tests.

Files:

• django/branches/magic-removal/django/db/models/fields/related.py (modified) (2 diffs)
• django/branches/magic-removal/django/db/models/manager.py (modified) (3 diffs)
• django/branches/magic-removal/django/db/models/query.py (modified) (1 diff)
• django/branches/magic-removal/tests/modeltests/get_latest/models.py (modified) (2 diffs)

django/branches/magic-removal/django/db/models/fields/related.py

@@ -127 +127 @@
-            manager.core_filters = {'%s__%s__exact' % (rel_field.name, instance_type._meta.pk.name): instance._get_pk_val()}
-
-        # Prepare the manager.
-        # TODO: Fix this hack?
-        # We're setting manager.model here because manager._prepare() expects
-        # that manager.model is set. This is slightly hackish.
-        manager.model = self.related.model
-        manager._prepare()
-
-        return manager
@@ -195 +190 @@
-
-        manager = RelatedManager()
-
-        # Prepare the manager.
-        # TODO: Fix this hack?
-        # We're setting manager.model here because manager._prepare() expects
-        # that manager.model is set. This is slightly hackish.
-        manager.model = self.rel_model
-        manager._prepare()
-
-        return manager

django/branches/magic-removal/django/db/models/manager.py

@@ -17 +17 @@
-            raise ValueError, "Model %s must specify a custom Manager, because it has a field named 'objects'" % name
-        cls.add_to_class('objects', Manager())
-        cls.objects._prepare()
-
-dispatcher.connect(ensure_default_manager, signal=signals.class_prepared)
@@ -32 +31 @@
-        self.model = None
-
-    def _prepare(self):
-        if self.model._meta.get_latest_by:
-            self.get_latest = self.__get_latest
-
-    def contribute_to_class(self, model, name):
-        # TODO: Use weakref because of possible memory leak / circular reference.
-        self.model = model
-        dispatcher.connect(self._prepare, signal=signals.class_prepared, sender=model)
-        setattr(model, name, ManagerDescriptor(self))
-        if not hasattr(model, '_default_manager') or self.creation_counter < model._default_manager.creation_counter:
-            model._default_manager = self
-
-    def __get_latest(self, *args, **kwargs):
-        kwargs['order_by'] = ('-' + self.model._meta.get_latest_by,)
-        kwargs['limit'] = 1
-        return self.get_object(*args, **kwargs)
-
-    #######################
@@ -90 +79 @@
-        return self.get_query_set().iterator(*args, **kwargs)
-
+    def latest(self, *args, **kwargs):
+        return self.get_query_set().latest(*args, **kwargs)
+
-    def order_by(self, *args, **kwargs):
-        return self.get_query_set().order_by(*args, **kwargs)

django/branches/magic-removal/django/db/models/query.py

@@ -162 +162 @@
-        assert len(obj_list) == 1, "get() returned more than one %s -- it returned %s! Lookup parameters were %s" % (self.model._meta.object_name, len(obj_list), kwargs)
-        return obj_list[0]
+
+    def latest(self, field_name=None):
+        """
+        Returns the latest object, according to the model's 'get_latest_by'
+        option or optional given field_name.
+        """
+        latest_by = field_name or self.model._meta.get_latest_by
+        assert bool(latest_by), "latest() requires either a field_name parameter or 'get_latest_by' in the model"
+        return self._clone(_limit=1, _order_by=('-'+latest_by,)).get()
-
-    def delete(self, *args, **kwargs):

django/branches/magic-removal/tests/modeltests/get_latest/models.py

@@ -13 +13 @@
-class Article(models.Model):
-    headline = models.CharField(maxlength=100)
-
+
+
-    class Meta:
-        get_latest_by = 'pub_date'
@@ -20 +21 @@
-        return self.headline
-
+class Person(models.Model):
+    name = models.CharField(maxlength=30)
+    birthday = models.DateField()
+
+    # Note that this model doesn't have "get_latest_by" set.
+
+    def __repr__(self):
+        return self.name
+
-API_TESTS = """
-# Because no Articles exist yet, get_latest() raises ArticleDoesNotExist.
-get_
+
-Traceback (most recent call last):
-    ...
-{'order_by': ('-pub_date',), 'limit': 1}
+...
-
-# Create a couple of Articles.
->>> from datetime import datetime
-id=None, headline='Article 1', pub_date=datetime(2005, 7, 26
+headline='Article 1', pub_date=datetime(2005, 7, 26), expire_date=datetime(2005, 9, 1
->>> a1.save()
-id=None, headline='Article 2', pub_date=datetime(2005, 7, 27
+headline='Article 2', pub_date=datetime(2005, 7, 27), expire_date=datetime(2005, 7, 28
->>> a2.save()
-id=None, headline='Article 3', pub_date=datetime(2005, 7
+headline='Article 3', pub_date=datetime(2005, 7, 27), expire_date=datetime(2005, 8
->>> a3.save()
-id=None, headline='Article 4', pub_date=datetime(2005, 7, 28
+headline='Article 4', pub_date=datetime(2005, 7, 28), expire_date=datetime(2005, 7, 30
->>> a4.save()
-
-# Get the latest Article.
-get_
+
-Article 4
+
+# Get the latest Article that matches certain filters.
+>>> Article.objects.filter(pub_date__lt=datetime(2005, 7, 27)).latest()
+Article 1
+
+# Pass a custom field name to latest() to change the field that's used to
+# determine the latest object.
+>>> Article.objects.latest('expire_date')
+Article 1
+
+>>> Article.objects.filter(pub_date__gt=datetime(2005, 7, 26)).latest('expire_date')
+Article 3
+
+# You can still use latest() with a model that doesn't have "get_latest_by"
+# set -- just pass in the field name manually.
+>>> p1 = Person(name='Ralph', birthday=datetime(1950, 1, 1))
+>>> p1.save()
+>>> p2 = Person(name='Stephanie', birthday=datetime(1960, 2, 3))
+>>> p2.save()
+>>> Person.objects.latest()
+Traceback (most recent call last):
+    ...
+AssertionError: latest() requires either a field_name parameter or 'get_latest_by' in the model
+
+>>> Person.objects.latest('birthday')
+Stephanie
-"""