extract get_current_user, fix tests

atst/domain/auth.py

@@ -8,11 +8,19 @@ def login_required(f):
 
     @wraps(f)
     def decorated_function(*args, **kwargs):
-        if session.get("user_id"):
-            g.user = Users.get(session.get("user_id"))
+        user = get_current_user()
+        if user:
+            g.user = user
             return f(*args, **kwargs)
 
         else:
             return redirect(url_for("atst.root"))
 
     return decorated_function
+
+def get_current_user():
+    user_id = session.get("user_id")
+    if user_id:
+        return Users.get(user_id)
+    else:
+        return False