feat(cookies): extend monkey-patching of Partitioned to make it a f…

…lag (#2428)

* feat(cookies): extend monkey-patching of Partitioned to make it flag

* fix(testing): restore an accidentally removed full stop

falcon/util/__init__.py

@@ -56,9 +56,11 @@
 #   attribute that will probably be added in Python 3.14.
 #   We do it this way because SimpleCookie does not give us a simple way to
 #   specify our own subclass of Morsel.
-_reserved_cookie_attrs = http_cookies.Morsel._reserved  # type: ignore
+_reserved_cookie_attrs = http_cookies.Morsel._reserved  # type: ignore[attr-defined]
 if 'partitioned' not in _reserved_cookie_attrs:  # pragma: no cover
     _reserved_cookie_attrs['partitioned'] = 'Partitioned'
+# NOTE(vytas): Partitioned is a boolean flag, similar to HttpOnly and Secure.
+http_cookies.Morsel._flags.add('partitioned')  # type: ignore[attr-defined]
 # NOTE(vytas): Morsel._reserved_defaults is a new optimization in Python 3.14+
 #   for faster initialization of Morsel instances.
 # TODO(vytas): Remove this part of monkey-patching in the case CPython 3.14

tests/test_cookies.py

@@ -285,12 +285,23 @@ def test_cookies_setable():
 
     resp.set_cookie('foo', 'wrong-cookie', max_age=301)
     resp.set_cookie('foo', 'bar', max_age=300)
-    morsel = resp._cookies['foo']
-
-    assert isinstance(morsel, http_cookies.Morsel)
-    assert morsel.key == 'foo'
-    assert morsel.value == 'bar'
-    assert morsel['max-age'] == 300
+    resp.set_cookie('bar', 'baz', same_site='None', partitioned=True)
+
+    morsel1 = resp._cookies['foo']
+    morsel2 = resp._cookies['bar']
+
+    assert isinstance(morsel1, http_cookies.Morsel)
+    assert morsel1.key == 'foo'
+    assert morsel1.value == 'bar'
+    assert morsel1['max-age'] == 300
+
+    assert isinstance(morsel2, http_cookies.Morsel)
+    assert morsel2.key == 'bar'
+    assert morsel2.value == 'baz'
+    assert morsel2['partitioned'] is True
+    assert morsel2.output() == (
+        'Set-Cookie: bar=baz; HttpOnly; Partitioned; SameSite=None; Secure'
+    )
 
 
 @pytest.mark.parametrize('cookie_name', ('foofloat', 'foostring'))