id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
24278	squashmigrations throws ValueError: need more than 1 value to unpack	Piotr Maliński	Marten Kenbeek	"When squashing several migrations I got an exception during squashmigrations:
{{{
Traceback (most recent call last):
  File ""/env/bin/django-admin.py"", line 5, in <module>
    management.execute_from_command_line()
  File ""/env/lib/python3.4/site-packages/django/core/management/__init__.py"", line 385, in execute_from_command_line
    utility.execute()
  File ""/env/lib/python3.4/site-packages/django/core/management/__init__.py"", line 377, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File ""/env/lib/python3.4/site-packages/django/core/management/base.py"", line 288, in run_from_argv
    self.execute(*args, **options.__dict__)
  File ""/env/lib/python3.4/site-packages/django/core/management/base.py"", line 338, in execute
    output = self.handle(*args, **options)
  File ""/env/lib/python3.4/site-packages/django/core/management/commands/squashmigrations.py"", line 122, in handle
    fh.write(writer.as_string())
  File ""/env/lib/python3.4/site-packages/django/db/migrations/writer.py"", line 130, in as_string
    operation_string, operation_imports = OperationWriter(operation).serialize()
  File ""/env/lib/python3.4/site-packages/django/db/migrations/writer.py"", line 87, in serialize
    arg_string, arg_imports = MigrationWriter.serialize(arg_value)
  File ""/env/lib/python3.4/site-packages/django/db/migrations/writer.py"", line 260, in serialize
    item_string, item_imports = cls.serialize(item)
  File ""/env/lib/python3.4/site-packages/django/db/migrations/writer.py"", line 327, in serialize
    return cls.serialize_deconstructed(*value.deconstruct())
  File ""/env/lib/python3.4/site-packages/django/db/migrations/writer.py"", line 223, in serialize_deconstructed
    module, name = path.rsplit(""."", 1)
ValueError: need more than 1 value to unpack
}}}

The ""path"" variable got a value of ""RenameField"" instead of django.something.someField. I found one ""migrations.RenameField"" in the migrations set and after removing it (and ""migrations.AlterField"" which also caused such exception) the squash passed.

The migration (operations) with those fields looks like so:

{{{
operations = [
        migrations.SeparateDatabaseAndState(state_operations=[
            migrations.RenameField(
                model_name='somemodel',
                old_name='some_old_name',
                new_name='new_name',
            ),
            migrations.AlterField(
                model_name='somemodel',
                name='new_name',
                field=models.BooleanField(db_column='some_old_name', default=False),
                preserve_default=True,
            ),
        ]),
    ]
}}}
"	Bug	closed	Migrations	1.8	Normal	fixed		Markus Holtermann michaelvantellingen@…	Ready for checkin	1	0	0	0	0	0