Fixed #28305 -- Fixed "Cannot change column 'x': used in a foreign key constraint" crash on MySQL with a sequence of AlterField or RenameField operations.

Regression in 45ded053b1.
This commit is contained in:
Tim Graham 2017-06-30 14:51:08 -04:00
parent d6859a1489
commit c3e0adcad8
5 changed files with 113 additions and 8 deletions

View file

@ -1322,6 +1322,83 @@ class OperationTests(OperationTestBase):
operation.database_backwards("test_alflpkfk", editor, new_state, project_state)
assertIdTypeEqualsFkType()
def test_alter_field_reloads_state_on_fk_target_changes(self):
"""
If AlterField doesn't reload state appropriately, the second AlterField
crashes on MySQL due to not dropping the PonyRider.pony foreign key
constraint before modifying the column.
"""
app_label = 'alter_alter_field_reloads_state_on_fk_target_changes'
project_state = self.apply_operations(app_label, ProjectState(), operations=[
migrations.CreateModel('Rider', fields=[
('id', models.CharField(primary_key=True, max_length=100)),
]),
migrations.CreateModel('Pony', fields=[
('id', models.CharField(primary_key=True, max_length=100)),
('rider', models.ForeignKey('%s.Rider' % app_label, models.CASCADE)),
]),
migrations.CreateModel('PonyRider', fields=[
('id', models.AutoField(primary_key=True)),
('pony', models.ForeignKey('%s.Pony' % app_label, models.CASCADE)),
]),
])
project_state = self.apply_operations(app_label, project_state, operations=[
migrations.AlterField('Rider', 'id', models.CharField(primary_key=True, max_length=99)),
migrations.AlterField('Pony', 'id', models.CharField(primary_key=True, max_length=99)),
])
def test_alter_field_reloads_state_on_fk_with_to_field_target_changes(self):
"""
If AlterField doesn't reload state appropriately, the second AlterField
crashes on MySQL due to not dropping the PonyRider.pony foreign key
constraint before modifying the column.
"""
app_label = 'alter_alter_field_reloads_state_on_fk_with_to_field_target_changes'
project_state = self.apply_operations(app_label, ProjectState(), operations=[
migrations.CreateModel('Rider', fields=[
('id', models.CharField(primary_key=True, max_length=100)),
('slug', models.CharField(unique=True, max_length=100)),
]),
migrations.CreateModel('Pony', fields=[
('id', models.CharField(primary_key=True, max_length=100)),
('rider', models.ForeignKey('%s.Rider' % app_label, models.CASCADE, to_field='slug')),
('slug', models.CharField(unique=True, max_length=100)),
]),
migrations.CreateModel('PonyRider', fields=[
('id', models.AutoField(primary_key=True)),
('pony', models.ForeignKey('%s.Pony' % app_label, models.CASCADE, to_field='slug')),
]),
])
project_state = self.apply_operations(app_label, project_state, operations=[
migrations.AlterField('Rider', 'slug', models.CharField(unique=True, max_length=99)),
migrations.AlterField('Pony', 'slug', models.CharField(unique=True, max_length=99)),
])
def test_rename_field_reloads_state_on_fk_target_changes(self):
"""
If RenameField doesn't reload state appropriately, the AlterField
crashes on MySQL due to not dropping the PonyRider.pony foreign key
constraint before modifying the column.
"""
app_label = 'alter_rename_field_reloads_state_on_fk_target_changes'
project_state = self.apply_operations(app_label, ProjectState(), operations=[
migrations.CreateModel('Rider', fields=[
('id', models.CharField(primary_key=True, max_length=100)),
]),
migrations.CreateModel('Pony', fields=[
('id', models.CharField(primary_key=True, max_length=100)),
('rider', models.ForeignKey('%s.Rider' % app_label, models.CASCADE)),
]),
migrations.CreateModel('PonyRider', fields=[
('id', models.AutoField(primary_key=True)),
('pony', models.ForeignKey('%s.Pony' % app_label, models.CASCADE)),
]),
])
project_state = self.apply_operations(app_label, project_state, operations=[
migrations.RenameField('Rider', 'id', 'id2'),
migrations.AlterField('Pony', 'id', models.CharField(primary_key=True, max_length=99)),
])
def test_rename_field(self):
"""
Tests the RenameField operation.