Add unit tests for LoginButton component with comprehensive coverage

backend/api/auth_api.py

@@ -3,9 +3,9 @@ import secrets, jwt
 from datetime import datetime, timedelta, timezone
 from models.user import User
 from flask import Blueprint, request, jsonify, current_app
-from utils.email_instance import email_sender
 from tinydb import Query
 import os
+import utils.email_sender as email_sender
 
 from api.utils import sanitize_email
 from config.paths import get_user_image_dir

backend/api/image_api.py

@@ -101,7 +101,10 @@ def request_image(id):
     if image.user_id is not None and image.user_id != user_id:
         return jsonify({'error': 'Forbidden: image does not belong to user', 'code': 'FORBIDDEN'}), 403
     filename = f"{image.id}{image.extension}"
-    filepath = os.path.abspath(os.path.join(get_user_image_dir(image.user_id or user_id), filename))
+    if image.user_id is None:
+        filepath = os.path.abspath(os.path.join(get_user_image_dir("default"), filename))
+    else:
+        filepath = os.path.abspath(os.path.join(get_user_image_dir(image.user_id), filename))
     if not os.path.exists(filepath):
         return jsonify({'error': 'File not found'}), 404
     return send_file(filepath)

backend/api/user_api.py

@@ -5,8 +5,7 @@ from db.db import users_db
 import jwt
 import random
 import string
-import smtplib
-from backend.utils.email_instance import email_sender
+import utils.email_sender as email_sender
 from datetime import datetime, timedelta
 from api.utils import get_validated_user_id