adding tests

Author: jszrajber

.github/workflows/django-tests.yml

@@ -0,0 +1,37 @@
+# Config file for GitHub Actions
+
+name: Django CI
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest  # Fastest option
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6   # Copies code on VM
+
+      - name: Set up Python
+        uses: actions/setup-python@v5   # Official GitHub tool
+        with:
+          python-version: '3.12'
+
+      - name: Install dependencies
+        run: |            # Everything below will be treated as one line
+          python -m pip install --upgrade pip
+          pip install -r requirements.txt
+
+      - name: Run migrations
+        env:    # Create env at virtual machine
+            DJANGO_SETTINGS_MODULE: backend.config.settings # Show where is the brain of the project
+        run: |
+            python manage.py migrate
+        
+
+      - name: Run tests
+        env:
+          DJANGO_SETTINGS_MODULE: backend.config.settings
+          PYTHONPATH: ${{ github.workspace }}  # github.workspace is a root dir, safe config
+        run: |
+            pytest --cov=backend/apps --cov-report=term-missing

backend/apps/conftest.py

@@ -0,0 +1,12 @@
+import pytest
+from model_bakery import baker
+
+
+@pytest.fixture
+def user(db):   # db needed to open connection with db
+    return baker.make("auth.User", username="Test_user")
+
+
+@pytest.fixture
+def post(db, user):
+    return baker.make("posts.Post", title="Testing", author=user)

backend/apps/interactions/migrations/0006_alter_comment_id_alter_follow_id_alter_like_id_and_more.py

@@ -0,0 +1,34 @@
+# Generated by Django 6.0 on 2026-02-09 19:44
+
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('interactions', '0005_alter_comment_id_alter_follow_id_alter_like_id'),
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='comment',
+            name='id',
+            field=models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID'),
+        ),
+        migrations.AlterField(
+            model_name='follow',
+            name='id',
+            field=models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID'),
+        ),
+        migrations.AlterField(
+            model_name='like',
+            name='id',
+            field=models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID'),
+        ),
+        migrations.AddConstraint(
+            model_name='follow',
+            constraint=models.CheckConstraint(condition=models.Q(('follower', models.F('following')), _negated=True), name='prevent_self_follow'),
+        ),
+    ]

backend/apps/interactions/models.py

@@ -34,6 +34,14 @@ class Follow(models.Model):
     class Meta:
         unique_together = ("follower", "following")
         ordering = ["-created_at"]
+        # Constraint to prevent self follow on database level
+        constraints = [
+            models.CheckConstraint(
+                # Object needed to negate it with ~, constraint doesn't accept other symbols than =
+                condition=~models.Q(follower=models.F("following")),    # models.F checks value in column 'following' for the same row
+                name="prevent_self_follow"
+            )
+        ]
 
     def __str__(self):
         return f"{self.follower.username} follows {self.following.username}"

backend/apps/interactions/tests.py

@@ -1,3 +1,65 @@
-from django.test import TestCase
+import pytest
+from model_bakery import baker
+from datetime import datetime
+from backend.apps.interactions.models import Like, Follow
+from django.db import IntegrityError
 
 # Create your tests here.
+
+
+@pytest.mark.django_db(transaction=True)    # Lets Django clean up database after error to continue assertions, no TransactionManagementError
+def test_like_creation_and_duplicate(user, post):
+    """
+    Check is like is created correctly,
+    error when duplicates
+    """
+    like = baker.make("interactions.Like", user=user, post=post)
+
+    assert Like.objects.count() == 1    # Manager doesn't exist for instance
+    assert like.post == post
+    assert like.user == user
+    assert isinstance(like.created_at, datetime)
+
+    with pytest.raises(IntegrityError):
+        baker.make("interactions.Like", user=user, post=post)   # We want this error, values must be unique
+
+    assert Like.objects.count() == 1    # To make sure there is still only one object
+
+
+@pytest.mark.django_db
+def test_comment_creation(user, post):
+    """
+    Checks if comment is created correctly
+    """
+
+    comment = baker.make("interactions.Comment", user=user, post=post)
+
+    assert comment.user == user
+    assert comment.post == post
+    assert comment.body is not None
+    assert isinstance(comment.created_at, datetime)
+
+
+@pytest.mark.django_db(transaction=True)
+def test_follow_creation(user):
+    """
+    Checks if follow is created correctly
+    Error if follow duplicates
+    Error if users tries to follow himself
+    """
+    user2 = baker.make("auth.User")
+    follow = baker.make("interactions.Follow", follower=user, following=user2)
+    assert Follow.objects.count() == 1
+    assert follow.follower == user
+    assert follow.following == user2
+    assert isinstance(follow.created_at, datetime)
+
+    # Calling error, duplicate
+    with pytest.raises(IntegrityError):
+        baker.make("interactions.Follow", follower=user, following=user2)
+
+    # Calling error, self follow
+    with pytest.raises(IntegrityError):
+        baker.make("interactions.Follow", follower=user, following=user)
+
+    assert Follow.objects.count() == 1

backend/apps/posts/migrations/0005_alter_post_id.py

@@ -0,0 +1,18 @@
+# Generated by Django 6.0 on 2026-02-09 19:44
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('posts', '0004_alter_post_id'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='post',
+            name='id',
+            field=models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID'),
+        ),
+    ]

backend/apps/posts/tests.py

@@ -1,3 +1,18 @@
 from django.test import TestCase
+import pytest
+from model_bakery import baker
+from datetime import datetime
 
 # Create your tests here.
+
+
+@pytest.mark.django_db
+def test_post_creation(user, post):
+    """
+    Check is post is created correctly
+    """
+
+    assert post.title == "Testing"
+    assert post.body is not None
+    assert post.author == user
+    assert isinstance(post.date, datetime)

backend/apps/users/migrations/0003_alter_profile_id.py

@@ -0,0 +1,18 @@
+# Generated by Django 6.0 on 2026-02-09 19:44
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('users', '0002_alter_profile_id_alter_profile_user'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='profile',
+            name='id',
+            field=models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID'),
+        ),
+    ]

backend/apps/users/tests.py

@@ -1,3 +1,16 @@
-from django.test import TestCase
+import pytest
+from model_bakery import baker
 
 # Create your tests here.
+
+
+@pytest.mark.django_db
+def test_user_profile_creation():
+    """
+    Check is user is created correctly
+    """
+    user = baker.make('auth.User', username="Test")
+
+    assert user.username == "Test"
+    assert user.is_active is True
+    assert user.id is not None

pytest.ini

@@ -0,0 +1,20 @@
+[pytest]
+
+# Settings path
+DJANGO_SETTINGS_MODULE = backend.config.settings
+
+# For apps imports
+pythonpath = . backend
+
+# Where to look for tests
+testpaths = backend/apps
+
+# Test filenames
+python_files = tests.py test_*.py *_tests.py
+
+# Django will tru to reuse db instead of creating one, no migrations issues
+addopts = -v --tb=short --reuse-db
+
+markers:
+    unit: logic tests
+    view: template and view test