Fixed #33199 -- Deprecated passing positional arguments to Signer/TimestampSigner.

Thanks Jacob Walls for the implementation idea.

docs/internals/deprecation.txt

@@ -42,6 +42,9 @@ details on these changes.
 * Support for passing encoded JSON string literals to ``JSONField`` and
   associated lookups and expressions will be removed.
 
+* Support for passing positional arguments to ``Signer`` and
+  ``TimestampSigner`` will be removed.
+
 .. _deprecation-removed-in-5.0:
 
 5.0

docs/releases/4.2.txt

@@ -540,3 +540,6 @@ Miscellaneous
 
 * ``TransactionTestCase.assertQuerysetEqual()`` is deprecated in favor of
   ``assertQuerySetEqual()``.
+
+* Passing positional arguments to ``Signer`` and ``TimestampSigner`` is
+  deprecated in favor of keyword-only arguments.

docs/topics/signing.txt

@@ -96,12 +96,12 @@ By default, the ``Signer`` class uses the :setting:`SECRET_KEY` setting to
 generate signatures. You can use a different secret by passing it to the
 ``Signer`` constructor::
 
-    >>> signer = Signer('my-other-secret')
+    >>> signer = Signer(key='my-other-secret')
     >>> value = signer.sign('My string')
     >>> value
     'My string:EkfQJafvGyiofrdGnuthdxImIJw'
 
-.. class:: Signer(key=None, sep=':', salt=None, algorithm=None, fallback_keys=None)
+.. class:: Signer(*, key=None, sep=':', salt=None, algorithm=None, fallback_keys=None)
 
     Returns a signer which uses ``key`` to generate signatures and ``sep`` to
     separate values. ``sep`` cannot be in the :rfc:`URL safe base64 alphabet
@@ -115,6 +115,10 @@ generate signatures. You can use a different secret by passing it to the
 
         The ``fallback_keys`` argument was added.
 
+    .. deprecated:: 4.2
+
+        Support for passing positional arguments is deprecated.
+
 Using the ``salt`` argument
 ---------------------------
 
@@ -172,7 +176,7 @@ created within a specified period of time::
     >>> signer.unsign(value, max_age=timedelta(seconds=20))
     'hello'
 
-.. class:: TimestampSigner(key=None, sep=':', salt=None, algorithm='sha256')
+.. class:: TimestampSigner(*, key=None, sep=':', salt=None, algorithm='sha256')
 
     .. method:: sign(value)
 
@@ -195,6 +199,10 @@ created within a specified period of time::
         otherwise raises ``SignatureExpired``. The ``max_age`` parameter can
         accept an integer or a :py:class:`datetime.timedelta` object.
 
+    .. deprecated:: 4.2
+
+        Support for passing positional arguments is deprecated.
+
 .. _signing-complex-data:
 
 Protecting complex data structures