Remove squashed migration and rely on run_before

The initial migration must continue to rely on the historical PageRevision model. Changing it to the generic revision model may cause errors with existing databases that have migrations applied in a certain order. New databases won't be able to migrate because they have no history and try to migrate the initial migration using the PageRevision model _after_ it was removed by Wagtail's migrations. To combat this, we add `run_before` to ensure we run the initial migration _before_ the PageRevision model is removed by Wagtail's migrations. I feel like this is a better solution then squashing the migration history.
wagtail-nest · Jul 27, 2023 · 27eb9bb · 27eb9bb
1 parent 3a557fb
commit 27eb9bb
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diff --git a/wagtail_ab_testing/migrations/0001_initial.py b/wagtail_ab_testing/migrations/0001_initial.py
@@ -12,6 +12,12 @@ class Migration(migrations.Migration):
         ('wagtailcore', '0052_pagelogentry'),
     ]
 
+    # Added for compatibility with Wagtail 4+
+    # This migration references the old PageRevision model and must run before it was migrated to a generic Revision model
+    run_before = [
+        ("wagtailcore", "0070_rename_pagerevision_revision")
+    ]
+
     operations = [
         migrations.CreateModel(
             name='AbTest',

diff --git a/wagtail_ab_testing/migrations/0001_squashed_0012_abtest_variant_revision.py b/wagtail_ab_testing/migrations/0001_squashed_0012_abtest_variant_revision.py
diff --git a/wagtail_ab_testing/migrations/0012_abtest_variant_revision.py b/wagtail_ab_testing/migrations/0012_abtest_variant_revision.py