Commit 537818af authored by Piper Merriam's avatar Piper Merriam Committed by Tim Graham
Browse files

Fixed #25185 -- Added support for functools.partial serialization in migrations

parent b1e552de

django/db/migrations/writer.py

+17 −0
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ from __future__ import unicode_literals 
import collections

import datetime

import decimal

import functools

import math

import os

import re
@@ -439,6 +440,22 @@ class MigrationWriter(object): 
            string, imports = OperationWriter(value, indentation=0).serialize()

            # Nested operation, trailing comma is handled in upper OperationWriter._write()

            return string.rstrip(','), imports

        elif isinstance(value, functools.partial):

            imports = {'import functools'}

            # Serialize functools.partial() arguments

            func_string, func_imports = cls.serialize(value.func)

            args_string, args_imports = cls.serialize(value.args)

            keywords_string, keywords_imports = cls.serialize(value.keywords)

            # Add any imports needed by arguments

            imports.update(func_imports)

            imports.update(args_imports)

            imports.update(keywords_imports)

            return (

                "functools.partial(%s, *%s, **%s)" % (

                    func_string, args_string, keywords_string,

                ),

                imports,

            )

        # Anything that knows how to deconstruct itself.

        elif hasattr(value, 'deconstruct'):

            return cls.serialize_deconstructed(*value.deconstruct())

docs/releases/1.9.txt

+2 −0
Original line number Diff line number Diff line
@@ -385,6 +385,8 @@ Migrations 
  :djadminopt:`migrate --fake-initial <--fake-initial>` to more easily detect

  initial migrations.



* Added support for serialization of ``functools.partial`` objects.



Models

^^^^^^

docs/topics/migrations.txt

+6 −0
Original line number Diff line number Diff line
@@ -652,11 +652,17 @@ Django can serialize the following: 
- ``datetime.date``, ``datetime.time``, and ``datetime.datetime`` instances

  (include those that are timezone-aware)

- ``decimal.Decimal`` instances

- ``functools.partial`` instances which have serializable ``func``, ``args``,

  and ``keywords`` values.

- Any Django field

- Any function or method reference (e.g. ``datetime.datetime.today``) (must be in module's top-level scope)

- Any class reference (must be in module's top-level scope)

- Anything with a custom ``deconstruct()`` method (:ref:`see below <custom-deconstruct-method>`)



.. versionchanged:: 1.9



    Serialization support for `functools.partial` was added.



Django can serialize the following on Python 3 only:



- Unbound methods used from within the class body (see below)

tests/migrations/test_writer.py

+8 −0
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
from __future__ import unicode_literals



import datetime

import functools

import math

import os

import re
@@ -414,6 +415,13 @@ class WriterTests(SimpleTestCase): 
        self.assertSerializedEqual(datetime.timedelta())

        self.assertSerializedEqual(datetime.timedelta(minutes=42))



    def test_serialize_functools_partial(self):

        value = functools.partial(datetime.timedelta, 1, seconds=2)

        result = self.serialize_round_trip(value)

        self.assertEqual(result.func, value.func)

        self.assertEqual(result.args, value.args)

        self.assertEqual(result.keywords, value.keywords)



    def test_simple_migration(self):

        """

        Tests serializing a simple migration.