Fixed #28718 -- Allowed user to request a password reset if their password doesn't use an enabled hasher.

Regression in aeb1389442d0f9669edf6660b747fd10693b63a7.
Reverted changes to is_password_usable() from
703c266682be39f7153498ad0d8031231f12ee79 and documentation changes from
92f48680dbd2e02f2b33f6ad0e35b7d337889fb2.

2 files changed, 12 insertions, 3 deletions

diff --git a/tests/auth_tests/test_hashers.py b/tests/auth_tests/test_hashers.py
index 51aaa3d72c..ab34ad78b6 100644
--- a/tests/auth_tests/test_hashers.py
+++ b/tests/auth_tests/test_hashers.py
@@ -276,9 +276,11 @@ class TestUtilsHashPass(SimpleTestCase):
         with self.assertRaisesMessage(ValueError, msg % 'lolcat'):
             identify_hasher('lolcat$salt$hash')
 
-    def test_bad_encoded(self):
-        self.assertFalse(is_password_usable('lètmein_badencoded'))
-        self.assertFalse(is_password_usable(''))
+    def test_is_password_usable(self):
+        passwords = ('lètmein_badencoded', '', None)
+        for password in passwords:
+            with self.subTest(password=password):
+                self.assertIs(is_password_usable(password), True)
 
     def test_low_level_pbkdf2(self):
         hasher = PBKDF2PasswordHasher()
diff --git a/tests/auth_tests/test_models.py b/tests/auth_tests/test_models.py
index 9438ed8aff..bd83b47677 100644
--- a/tests/auth_tests/test_models.py
+++ b/tests/auth_tests/test_models.py
@@ -158,6 +158,13 @@ class UserManagerTestCase(TestCase):
 
 class AbstractBaseUserTests(TestCase):
 
+    def test_has_usable_password(self):
+        """
+        Passwords are usable even if they don't correspond to a hasher in
+        settings.PASSWORD_HASHERS.
+        """
+        self.assertIs(User(password='some-gibbberish').has_usable_password(), True)
+
     def test_normalize_username(self):
         self.assertEqual(IntegerUsernameUser().normalize_username(123), 123)