From 7d92e3982f8c4c38d9c7223d5fd3a05774ed8682 Mon Sep 17 00:00:00 2001
From: Matt Westcott <matt@west.co.tt>
Date: Thu, 22 Oct 2020 16:32:03 +0100
Subject: [PATCH] Fix steps for adding translations to an existin snippet

* Fix BootstrapTranslatableMixin to skip TranslatableModel's system check for the missing unique constraint
* Fix incorrect import for BootstrapTranslatableModel and use of `--empty` in final schema migration
* Clarify handling of Meta classes, the fact that you need to run makemigrations for step 1, and what to do for the non-nullable 'locale' prompt
---
 docs/advanced_topics/i18n.rst | 19 +++++++++++++++++--
 wagtail/core/models.py        |  5 +++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/docs/advanced_topics/i18n.rst b/docs/advanced_topics/i18n.rst
index a6fb26ff38..ceea31ea42 100644
--- a/docs/advanced_topics/i18n.rst
+++ b/docs/advanced_topics/i18n.rst
@@ -508,6 +508,13 @@ This will add the two fields without any constraints:
     class Advert(BootstrapTranslatableMixin, models.Model):
         name = models.CharField(max_length=255)
 
+        # if the model has a Meta class, ensure it inherits from
+        # BootstrapTranslatableMixin.Meta too
+        class Meta(BootstrapTranslatableMixin.Meta):
+            verbose_name = 'adverts'
+
+Run ``python manage.py makemigrations myapp`` to generate the schema migration.
+
 Step 2: Create a data migration
 *******************************
 
@@ -524,7 +531,7 @@ in that app:
 .. code-block:: python
 
     from django.db import migrations
-    from wagtail_localize.bootstrap import BootstrapTranslatableModel
+    from wagtail.core.models import BootstrapTranslatableModel
 
     class Migration(migrations.Migration):
         dependencies = [
@@ -556,6 +563,9 @@ constraints:
     class Advert(TranslatableMixin, models.Model):  # Change this line
         name = models.CharField(max_length=255)
 
+        class Meta(TranslatableMixin.Meta):  # Change this line, if present
+            verbose_name = 'adverts'
+
 Step 4: Run ``makemigrations`` to generate schema migrations, then migrate!
 ***************************************************************************
 
@@ -565,9 +575,14 @@ migrations:
 
 .. code-block:: bash
 
-    python manage.py makemigrations myapp --empty
+    python manage.py makemigrations myapp
     python manage.py migrate
 
+When prompted to select a fix for the nullable field 'locale' being changed to
+non-nullable, select the option "Ignore for now" (as this has been handled by the
+data migration).
+
+
 Translation workflow
 --------------------
 
diff --git a/wagtail/core/models.py b/wagtail/core/models.py
index 9996cdf3ab..d0ad2d34f8 100644
--- a/wagtail/core/models.py
+++ b/wagtail/core/models.py
@@ -574,6 +574,11 @@ class BootstrapTranslatableMixin(TranslatableMixin):
         Locale, on_delete=models.PROTECT, null=True, related_name="+", editable=False
     )
 
+    @classmethod
+    def check(cls, **kwargs):
+        # skip the check in TranslatableMixin that enforces the unique-together constraint
+        return super(TranslatableMixin, cls).check(**kwargs)
+
     class Meta:
         abstract = True