Fixed #27310 -- Stopped rendering apps in RenameModel.state_forwards.

Thanks Tim for the review.
This commit is contained in:
Simon Charette 2016-11-04 08:58:46 -04:00
parent 8e3a72f4fb
commit ecd625e830
2 changed files with 46 additions and 63 deletions

View File

@ -3,6 +3,7 @@ from __future__ import unicode_literals
from django.db import models
from django.db.migrations.operations.base import Operation
from django.db.migrations.state import ModelState
from django.db.models.fields.related import RECURSIVE_RELATIONSHIP_CONSTANT
from django.db.models.options import normalize_together
from django.utils import six
from django.utils.functional import cached_property
@ -277,70 +278,50 @@ class RenameModel(ModelOperation):
kwargs
)
def _get_model_tuple(self, remote_model, app_label, model_name):
if remote_model == RECURSIVE_RELATIONSHIP_CONSTANT:
return app_label, model_name.lower()
elif '.' in remote_model:
return tuple(remote_model.lower().split('.'))
else:
return app_label, remote_model.lower()
def state_forwards(self, app_label, state):
# In cases where state doesn't have rendered apps, prevent subsequent
# reload_model() calls from rendering models for performance
# reasons. This method should be refactored to avoid relying on
# state.apps (#27310).
reset_apps = 'apps' not in state.__dict__
apps = state.apps
model = apps.get_model(app_label, self.old_name)
model._meta.apps = apps
# Get all of the related objects we need to repoint
all_related_objects = (
f for f in model._meta.get_fields(include_hidden=True)
if f.auto_created and not f.concrete and (not f.hidden or f.many_to_many)
# Add a new model.
renamed_model = state.models[app_label, self.old_name_lower].clone()
renamed_model.name = self.new_name
state.models[app_label, self.new_name_lower] = renamed_model
# Repoint all fields pointing to the old model to the new one.
old_model_tuple = app_label, self.old_name_lower
new_remote_model = '%s.%s' % (app_label, self.new_name)
for (model_app_label, model_name), model_state in state.models.items():
model_changed = False
for index, (name, field) in enumerate(model_state.fields):
changed_field = None
remote_field = field.remote_field
if remote_field:
remote_model_tuple = self._get_model_tuple(
remote_field.model, model_app_label, model_name
)
if reset_apps:
del state.__dict__['apps']
# Rename the model
state.models[app_label, self.new_name_lower] = state.models[app_label, self.old_name_lower]
state.models[app_label, self.new_name_lower].name = self.new_name
if remote_model_tuple == old_model_tuple:
changed_field = field.clone()
changed_field.remote_field.model = new_remote_model
through_model = getattr(remote_field, 'through', None)
if through_model:
through_model_tuple = self._get_model_tuple(
through_model, model_app_label, model_name
)
if through_model_tuple == old_model_tuple:
if changed_field is None:
changed_field = field.clone()
changed_field.remote_field.through = new_remote_model
if changed_field:
model_state.fields[index] = name, changed_field
model_changed = True
if model_changed:
state.reload_model(model_app_label, model_name)
# Remove the old model.
state.remove_model(app_label, self.old_name_lower)
# Repoint the FKs and M2Ms pointing to us
for related_object in all_related_objects:
if related_object.model is not model:
# The model being renamed does not participate in this relation
# directly. Rather, a superclass does.
continue
# Use the new related key for self referential related objects.
if related_object.related_model == model:
related_key = (app_label, self.new_name_lower)
else:
related_key = (
related_object.related_model._meta.app_label,
related_object.related_model._meta.model_name,
)
new_fields = []
for name, field in state.models[related_key].fields:
if name == related_object.field.name:
field = field.clone()
field.remote_field.model = "%s.%s" % (app_label, self.new_name)
new_fields.append((name, field))
state.models[related_key].fields = new_fields
state.reload_model(*related_key)
# Repoint M2Ms with through pointing to us
related_models = {
f.remote_field.model for f in model._meta.fields
if getattr(f.remote_field, 'model', None)
}
model_name = '%s.%s' % (app_label, self.old_name)
for related_model in related_models:
if related_model == model:
related_key = (app_label, self.new_name_lower)
else:
related_key = (related_model._meta.app_label, related_model._meta.model_name)
new_fields = []
changed = False
for name, field in state.models[related_key].fields:
if field.is_relation and field.many_to_many and field.remote_field.through == model_name:
field = field.clone()
field.remote_field.through = '%s.%s' % (app_label, self.new_name)
changed = True
new_fields.append((name, field))
if changed:
state.models[related_key].fields = new_fields
state.reload_model(*related_key)
state.reload_model(app_label, self.new_name_lower)
def database_forwards(self, app_label, schema_editor, from_state, to_state):

View File

@ -624,9 +624,11 @@ class OperationTests(OperationTestBase):
self.assertIn(("test_rmwsrf", "horserider"), new_state.models)
# Remember, RenameModel also repoints all incoming FKs and M2Ms
self.assertEqual(
"test_rmwsrf.HorseRider",
'self',
new_state.models["test_rmwsrf", "horserider"].fields[2][1].remote_field.model
)
HorseRider = new_state.apps.get_model('test_rmwsrf', 'horserider')
self.assertIs(HorseRider._meta.get_field('horserider').remote_field.model, HorseRider)
# Test the database alteration
self.assertTableExists("test_rmwsrf_rider")
self.assertTableNotExists("test_rmwsrf_horserider")