Commit 3818d964 authored by Tim Graham's avatar Tim Graham
Browse files

Fixed #22435 -- Prevented adding a ManyToManyField from prompting for a default. 

Thanks andrewsg for the report.
parent 142c2721

django/db/migrations/autodetector.py

+2 −1
Original line number Diff line number Diff line 
import re

import datetime



from django.db import models

from django.db.migrations import operations

from django.db.migrations.migration import Migration

from django.db.migrations.questioner import MigrationQuestioner
@@ -299,7 +300,7 @@ class MigrationAutodetector(object): 
            if found_rename:

                continue

            # You can't just add NOT NULL fields with no default

            if not field.null and not field.has_default():

            if not field.null and not field.has_default() and not isinstance(field, models.ManyToManyField):

                field = field.clone()

                field.default = self.questioner.ask_not_null_addition(field_name, model_name)

                self.add_to_migration(

tests/migrations/test_autodetector.py

+26 −0
Original line number Diff line number Diff line
@@ -37,6 +37,10 @@ class AutodetectorTests(TestCase): 
    author_proxy_notproxy = ModelState("testapp", "AuthorProxy", [], {}, ("testapp.author", ))

    author_unmanaged = ModelState("testapp", "AuthorUnmanaged", [], {"managed": False}, ("testapp.author", ))

    author_unmanaged_managed = ModelState("testapp", "AuthorUnmanaged", [], {}, ("testapp.author", ))

    author_with_m2m = ModelState("testapp", "Author", [

        ("id", models.AutoField(primary_key=True)),

        ("publishers", models.ManyToManyField("testapp.Publisher")),

    ])

    publisher = ModelState("testapp", "Publisher", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=100))])

    publisher_with_author = ModelState("testapp", "Publisher", [("id", models.AutoField(primary_key=True)), ("author", models.ForeignKey("testapp.Author")), ("name", models.CharField(max_length=100))])

    publisher_with_book = ModelState("testapp", "Publisher", [("id", models.AutoField(primary_key=True)), ("author", models.ForeignKey("otherapp.Book")), ("name", models.CharField(max_length=100))])
@@ -619,6 +623,28 @@ class AutodetectorTests(TestCase): 
        self.assertEqual(action.__class__.__name__, "DeleteModel")

        self.assertEqual(action.name, "Publisher")



    def test_add_many_to_many(self):

        """

        Adding a ManyToManyField should not prompt for a default (#22435).

        """

        class CustomQuestioner(MigrationQuestioner):

            def ask_not_null_addition(self, field_name, model_name):

                raise Exception("Should not have prompted for not null addition")



        before = self.make_project_state([self.author_empty, self.publisher])

        # Add ManyToManyField to author model

        after = self.make_project_state([self.author_with_m2m, self.publisher])

        autodetector = MigrationAutodetector(before, after, CustomQuestioner())

        changes = autodetector._detect_changes()

        # Right number of migrations?

        self.assertEqual(len(changes['testapp']), 1)

        migration = changes['testapp'][0]

        # Right actions in right order?

        self.assertEqual(len(migration.operations), 1)

        action = migration.operations[0]

        self.assertEqual(action.__class__.__name__, "AddField")

        self.assertEqual(action.name, "publishers")



    def test_many_to_many_removed_before_through_model(self):

        """

        Removing a ManyToManyField and the "through" model in the same change must remove