deprecate total_seconds

CHANGES.rst

@@ -72,6 +72,8 @@ Unreleased
 -   Support nesting blueprints. :issue:`593, 1548`, :pr:`3923`
 -   ``flask shell`` sets up tab and history completion like the default
     ``python`` shell if ``readline`` is installed. :issue:`3941`
+-   ``helpers.total_seconds()`` is deprecated. Use
+    ``timedelta.total_seconds()`` instead. :pr:`3962`
 
 
 Version 1.1.2

src/flask/helpers.py

@@ -709,7 +709,17 @@ def total_seconds(td):
 
     :returns: number of seconds
     :rtype: int
+
+    .. deprecated:: 2.0
+        Will be removed in Flask 2.1. Use
+        :meth:`timedelta.total_seconds` instead.
     """
+    warnings.warn(
+        "'total_seconds' is deprecated and will be removed in Flask"
+        " 2.1. Use 'timedelta.total_seconds' instead.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
     return td.days * 60 * 60 * 24 + td.seconds
 
 

src/flask/sessions.py

@@ -8,7 +8,6 @@ from itsdangerous import URLSafeTimedSerializer
 from werkzeug.datastructures import CallbackDict
 
 from .helpers import is_ip
-from .helpers import total_seconds
 from .json.tag import TaggedJSONSerializer
 
 
@@ -340,7 +339,7 @@ class SecureCookieSessionInterface(SessionInterface):
         val = request.cookies.get(self.get_cookie_name(app))
         if not val:
             return self.session_class()
-        max_age = total_seconds(app.permanent_session_lifetime)
+        max_age = int(app.permanent_session_lifetime.total_seconds())
         try:
             data = s.loads(val, max_age=max_age)
             return self.session_class(data)