gh-68966: Deprecate the mailcap module (#91951)

Author: vstinner

Doc/library/mailcap.rst

@@ -3,9 +3,14 @@
 
 .. module:: mailcap
    :synopsis: Mailcap file handling.
+   :deprecated:
 
 **Source code:** :source:`Lib/mailcap.py`
 
+.. deprecated:: 3.11
+   The :mod:`mailcap` module is deprecated. See :pep:`594` for the rationale
+   and the :mod:`mimetypes` module for an alternative.
+
 --------------
 
 Mailcap files are used to configure how MIME-aware applications such as mail

Doc/library/netdata.rst

@@ -13,7 +13,6 @@ on the internet.
 
    email.rst
    json.rst
-   mailcap.rst
    mailbox.rst
    mimetypes.rst
    base64.rst

Doc/library/superseded.rst

@@ -20,9 +20,10 @@ backwards compatibility. They have been superseded by other modules.
    crypt.rst
    imghdr.rst
    imp.rst
+   mailcap.rst
    msilib.rst
-   nntplib.rst
    nis.rst
+   nntplib.rst
    optparse.rst
    ossaudiodev.rst
    pipes.rst

Doc/whatsnew/3.11.rst

@@ -1061,6 +1061,7 @@ Deprecated
   * :mod:`chunk`
   * :mod:`crypt`
   * :mod:`imghdr`
+  * :mod:`mailcap`
   * :mod:`msilib`
   * :mod:`nis`
   * :mod:`nntplib`
@@ -1071,7 +1072,8 @@ Deprecated
   * :mod:`sunau`
   * :mod:`telnetlib`
 
-  (Contributed by Brett Cannon in :issue:`47061`.)
+  (Contributed by Brett Cannon in :issue:`47061` and Victor Stinner in
+  :gh:`68966`.)
 
 
 Removed

Lib/mailcap.py

@@ -6,6 +6,12 @@
 __all__ = ["getcaps","findmatch"]
 
 
+_DEPRECATION_MSG = ('The {name} module is deprecated and will be removed in '
+                    'Python {remove}. See the mimetypes module for an '
+                    'alternative.')
+warnings._deprecated(__name__, _DEPRECATION_MSG, remove=(3, 13))
+
+
 def lineno_sort_key(entry):
     # Sort in ascending order, with unspecified entries at the end
     if 'lineno' in entry:

Lib/test/test_mailcap.py

@@ -1,10 +1,15 @@
-import mailcap
-import os
 import copy
+import os
+import sys
 import test.support
-from test.support import os_helper
 import unittest
-import sys
+import warnings
+from test.support import os_helper
+from test.support import warnings_helper
+
+
+mailcap = warnings_helper.import_deprecated('mailcap')
+
 
 # Location of mailcap file
 MAILCAPFILE = test.support.findfile("mailcap.txt")

Misc/NEWS.d/next/Library/2022-04-26-09-09-07.gh-issue-68966.roapI2.rst

@@ -0,0 +1,3 @@
+The :mod:`mailcap` module is now deprecated and will be removed in Python 3.13.
+See :pep:`594` for the rationale and the :mod:`mimetypes` module for an
+alternative. Patch by Victor Stinner.