[WIP] for issue 713: INTERNALERROR due to DB access in repr

pytest_django_test/app/migrations/0002_seed_data.py

@@ -0,0 +1,9 @@
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    """Placeholder migration to be replaced in tests."""
+
+    dependencies = [
+        ('app', '0001_initial'),
+    ]

tests/test_bad_environment.py

@@ -0,0 +1,109 @@
+bad_migration = """
+# Generated by Django 2.0.8 on 2018-09-05 14:47
+
+from django.db import migrations
+
+
+def cb_seed_items(apps, schema_editor):
+    Item = apps.get_model('app', 'Item')
+    Item.objects.get(name='This one is not there')
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('app', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.RunPython(cb_seed_items),
+    ]
+"""
+
+
+class TestNativeMigrations(object):
+    """ Tests for Django Migrations """
+
+    def test_migration_should_not_cause_internal_error(self, django_testdir):
+        django_testdir.create_test_module(
+            """
+            import pytest
+
+            @pytest.mark.django_db
+            def test_inner_migrations():
+                from .app.models import Item
+                Item.objects.create()
+        """
+        )
+
+        migration_file = django_testdir.project_root.join(
+            "tpkg/app/migrations/0002_seed_data.py"
+        )
+        assert migration_file.isfile()
+        migration_file.write(
+            bad_migration, ensure=True
+        )
+
+        result = django_testdir.runpytest_subprocess(
+            "-vv", "-s",
+        )
+        assert result.ret == 1
+        assert "Operations to perform:" in result.stdout.str()
+        result.stdout.fnmatch_lines([
+            "Running migrations:",
+            "E           __fake__.Item.DoesNotExist: Item matching query does not exist.",
+            "*= 1 error in *",
+        ])
+
+    def test_migrations_run(self, django_testdir):
+        testdir = django_testdir
+        testdir.create_test_module(
+            """
+            import pytest
+
+            @pytest.mark.django_db
+            def test_inner_migrations():
+                from .app.models import Item
+                Item.objects.create()
+            """
+        )
+
+        testdir.create_app_file(
+            """
+            from django.db import migrations, models
+
+            def print_it(apps, schema_editor):
+                print("mark_migrations_run")
+
+            class Migration(migrations.Migration):
+
+                dependencies = []
+
+                operations = [
+                    migrations.CreateModel(
+                        name='Item',
+                        fields=[
+                            ('id', models.AutoField(serialize=False,
+                                                    auto_created=True,
+                                                    primary_key=True)),
+                            ('name', models.CharField(max_length=100)),
+                        ],
+                        options={
+                        },
+                        bases=(models.Model,),
+                    ),
+                    migrations.RunPython(
+                        print_it,
+                    ),
+                ]
+            """,
+            "migrations/0001_initial.py",
+        )
+        result = testdir.runpytest_subprocess("--tb=short", "-v", "-s")
+        assert result.ret == 0
+        result.stdout.fnmatch_lines(["*mark_migrations_run*"])
+
+        result = testdir.runpytest_subprocess(
+            "--no-migrations", "--migrations", "--tb=short", "-v", "-s"
+        )
+        assert result.ret == 0
+        result.stdout.fnmatch_lines(["*mark_migrations_run*"])