Add tests for activity signup and unregistration functionality

Author: briefjo

requirements.txt

@@ -1,4 +1,5 @@
 fastapi
 uvicorn
 httpx
-watchfiles
+watchfiles
+pytest

tests/__init__.py

@@ -0,0 +1,150 @@
+import copy
+import pytest
+from fastapi.testclient import TestClient
+from src.app import app, activities
+
+@pytest.fixture(autouse=True)
+def reset_activities():
+    """Reset activities to original state before each test."""
+    original = copy.deepcopy(activities)
+    yield
+    activities.clear()
+    activities.update(original)
+
+
+client = TestClient(app)
+
+
+# ── GET / ────────────────────────────────────────────────────────────────
+
+def test_root_redirect():
+    # Arrange
+    url = "/"
+
+    # Act
+    response = client.get(url, follow_redirects=False)
+
+    # Assert
+    assert response.status_code == 307
+    assert response.headers["location"] == "/static/index.html"
+
+
+# ── GET /activities ──────────────────────────────────────────────────────
+
+def test_get_activities_returns_all():
+    # Arrange
+    expected_keys = {"description", "schedule", "max_participants", "participants"}
+
+    # Act
+    response = client.get("/activities")
+
+    # Assert
+    assert response.status_code == 200
+    data = response.json()
+    assert isinstance(data, dict)
+    assert len(data) == len(activities)
+    for name, details in data.items():
+        assert expected_keys == set(details.keys())
+        assert isinstance(details["participants"], list)
+
+
+# ── POST /activities/{name}/signup ───────────────────────────────────────
+
+def test_signup_success():
+    # Arrange
+    activity_name = "Chess Club"
+    email = "newstudent@mergington.edu"
+
+    # Act
+    response = client.post(
+        f"/activities/{activity_name}/signup",
+        params={"email": email},
+    )
+
+    # Assert
+    assert response.status_code == 200
+    assert email in activities[activity_name]["participants"]
+    assert response.json()["message"] == f"Signed up {email} for {activity_name}"
+
+
+def test_signup_duplicate():
+    # Arrange
+    activity_name = "Chess Club"
+    email = "michael@mergington.edu"  # already in participants
+
+    # Act
+    response = client.post(
+        f"/activities/{activity_name}/signup",
+        params={"email": email},
+    )
+
+    # Assert
+    assert response.status_code == 400
+    assert response.json()["detail"] == "Already signed up"
+
+
+def test_signup_unknown_activity():
+    # Arrange
+    activity_name = "Nonexistent Club"
+    email = "student@mergington.edu"
+
+    # Act
+    response = client.post(
+        f"/activities/{activity_name}/signup",
+        params={"email": email},
+    )
+
+    # Assert
+    assert response.status_code == 404
+    assert response.json()["detail"] == "Activity not found"
+
+
+# ── DELETE /activities/{name}/signup ─────────────────────────────────────
+
+def test_unregister_success():
+    # Arrange
+    activity_name = "Chess Club"
+    email = "michael@mergington.edu"  # existing participant
+
+    # Act
+    response = client.delete(
+        f"/activities/{activity_name}/signup",
+        params={"email": email},
+    )
+
+    # Assert
+    assert response.status_code == 200
+    assert email not in activities[activity_name]["participants"]
+    assert response.json()["message"] == f"Unregistered {email} from {activity_name}"
+
+
+def test_unregister_not_signed_up():
+    # Arrange
+    activity_name = "Chess Club"
+    email = "unknown@mergington.edu"
+
+    # Act
+    response = client.delete(
+        f"/activities/{activity_name}/signup",
+        params={"email": email},
+    )
+
+    # Assert
+    assert response.status_code == 400
+    assert response.json()["detail"] == "Student not signed up for this activity"
+
+
+def test_unregister_unknown_activity():
+    # Arrange
+    activity_name = "Nonexistent Club"
+    email = "student@mergington.edu"
+
+    # Act
+    response = client.delete(
+        f"/activities/{activity_name}/signup",
+        params={"email": email},
+    )
+
+    # Assert
+    assert response.status_code == 404
+    assert response.json()["detail"] == "Activity not found"