Merge pull request #1271 from SchrodingersGat/migration-unit-test

Migration unit test

InvenTree/part/migrations/0020_auto_20190908_0404.py

@@ -12,6 +12,8 @@ def update_tree(apps, schema_editor):
 
 class Migration(migrations.Migration):
 
+    atomic = False
+
     dependencies = [
         ('part', '0019_auto_20190908_0404'),
     ]

InvenTree/part/migrations/0034_auto_20200404_1238.py

@@ -18,6 +18,8 @@ def create_thumbnails(apps, schema_editor):
 
 class Migration(migrations.Migration):
 
+    atomic = False
+
     dependencies = [
         ('part', '0033_auto_20200404_0445'),
     ]

InvenTree/part/migrations/0039_auto_20200515_1127.py

@@ -16,6 +16,8 @@ def nupdate_tree(apps, schema_editor):
 
 class Migration(migrations.Migration):
 
+    atomic = False
+
     dependencies = [
         ('part', '0038_auto_20200513_0016'),
     ]

InvenTree/part/migrations/0056_auto_20201110_1125.py

@@ -138,6 +138,8 @@ def reverse_currencies(apps, schema_editor):
 
 class Migration(migrations.Migration):
 
+    atomic = False
+
     dependencies = [
         ('part', '0055_auto_20201110_1001'),
     ]

InvenTree/part/test_migrations.py

@@ -0,0 +1,51 @@
+"""
+Unit tests for the part model database migrations
+"""
+
+from django_test_migrations.contrib.unittest_case import MigratorTestCase
+
+from InvenTree import helpers
+
+
+class TestForwardMigrations(MigratorTestCase):
+    """
+    Test entire schema migration sequence for the part app
+    """
+
+    migrate_from = ('part', helpers.getOldestMigrationFile('part'))
+    migrate_to = ('part', helpers.getNewestMigrationFile('part'))
+
+    def prepare(self):
+        """
+        Create initial data
+        """
+
+        Part = self.old_state.apps.get_model('part', 'part')
+
+        Part.objects.create(name='A', description='My part A')
+        Part.objects.create(name='B', description='My part B')
+        Part.objects.create(name='C', description='My part C')
+        Part.objects.create(name='D', description='My part D')
+        Part.objects.create(name='E', description='My part E')
+
+        # Extract one part object to investigate
+        p = Part.objects.all().last()
+
+        # Initially some fields are not present
+        with self.assertRaises(AttributeError):
+            print(p.has_variants)
+        
+        with self.assertRaises(AttributeError):
+            print(p.is_template)
+
+    def test_models_exist(self):
+
+        Part = self.new_state.apps.get_model('part', 'part')
+
+        self.assertEqual(Part.objects.count(), 5)
+
+        for part in Part.objects.all():
+            part.is_template = True
+            part.save()
+            part.is_template = False
+            part.save()