Add test migration in folder

tests/test_project_fixtures/test_correct_project/apps/test_app3/admin.py

@@ -0,0 +1,3 @@
+from django.contrib import admin
+
+# Register your models here.

tests/test_project_fixtures/test_correct_project/apps/test_app3/apps.py

@@ -0,0 +1,5 @@
+from django.apps import AppConfig
+
+
+class TestApp3Config(AppConfig):
+    name = 'test_app3'

tests/test_project_fixtures/test_correct_project/apps/test_app3/migrations/0001_initial.py

@@ -0,0 +1,21 @@
+# Generated by Django 2.1.4 on 2019-01-04 20:55
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='C',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('not_null_field', models.IntegerField()),
+            ],
+        ),
+    ]

tests/test_project_fixtures/test_correct_project/apps/test_app3/models.py

@@ -0,0 +1,4 @@
+from django.db import models
+
+class C(models.Model):
+	not_null_field = models.IntegerField(null=False)

tests/test_project_fixtures/test_correct_project/apps/test_app3/tests.py

@@ -0,0 +1,3 @@
+from django.test import TestCase
+
+# Create your tests here.

tests/test_project_fixtures/test_correct_project/apps/test_app3/views.py

@@ -0,0 +1,3 @@
+from django.shortcuts import render
+
+# Create your views here.

tests/test_project_fixtures/test_correct_project/test_project/settings.py

@@ -11,10 +11,12 @@ https://docs.djangoproject.com/en/1.11/ref/settings/
 """
 
 import os
+import sys
 
 # Build paths inside the project like this: os.path.join(BASE_DIR, ...)
 BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 
+sys.path.insert(0, os.path.join(BASE_DIR, 'apps'))
 
 # Quick-start development settings - unsuitable for production
 # See https://docs.djangoproject.com/en/1.11/howto/deployment/checklist/
@@ -38,7 +40,8 @@ INSTALLED_APPS = [
     'django.contrib.messages',
     'django.contrib.staticfiles',
     'test_app1',
-    'test_app2'
+    'test_app2',
+    'apps.test_app3',
 ]
 
 MIDDLEWARE = [

tests/unit/test_linter.py

@@ -80,12 +80,13 @@ class TestLinterFunctions(unittest.TestCase):
     def test_gather_all_migrations(self):
         linter = MigrationLinter(fixtures.CORRECT_PROJECT)
         migrations = linter._gather_all_migrations()
-        self.assertEqual(len(migrations), 3)
+        self.assertEqual(len(migrations), 4)
         self.assertEqual(
             sorted(migrations),
             sorted([
                 ("test_app1", "0001_initial"),
                 ("test_app1", "0002_a_new_null_field"),
                 ("test_app2", "0001_foo"),
+                ("test_app3", "0001_initial"),
             ])
         )