gh-122953: applied reviewed fixes - retaining removed documentation, space added accidently in test, inlining one use helper functions, adding whats new and fixing ci failure

Author: durawat

Doc/library/imaplib.rst

@@ -15,9 +15,10 @@
 
 This module defines three classes, :class:`IMAP4`, :class:`IMAP4_SSL` and
 :class:`IMAP4_stream`, which encapsulate a connection to an IMAP4 server and
-implement IMAP4rev1 and IMAP4rev2 client protocol features. It is backward
-compatible with IMAP4 (:rfc:`1730`) servers, but note that the ``STATUS``
-command is not supported in IMAP4.
+implement a large subset of the IMAP4rev1 client protocol as defined in
+:rfc:`2060` and adds support for IMAP4rev2 client protocol as defined in
+:rfc:`9051`.  It is backward compatible with IMAP4 (:rfc:`1730`) servers, but
+note that the ``STATUS`` command is not supported in IMAP4.
 
 .. include:: ../includes/wasm-notavail.rst
 

Doc/whatsnew/3.16.rst

@@ -94,6 +94,11 @@ gzip
   which is passed on to the constructor of the :class:`~gzip.GzipFile` class.
   (Contributed by Marin Misur in :gh:`91372`.)
 
+imaplib
+-------
+
+* Add support for IMAP4rev2.
+
 os
 --
 

Lib/imaplib.py

@@ -270,54 +270,36 @@ def _connect(self):
 
     def _set_protocol_version(self):
 
-        if self._should_use_rev1_mode_for_dual_support():
-            self._activate_rev1_mode()
+        if 'IMAP4REV2' in self.capabilities and 'IMAP4REV1' in self.capabilities:
+            self.PROTOCOL_VERSION = 'IMAP4REV1'
+            self._mode_ascii()
             return
 
         for version in AllowedVersions:
             if not version in self.capabilities:
                 continue
             if version == 'IMAP4REV2':
-                self._activate_rev2_mode()
+                self.PROTOCOL_VERSION = 'IMAP4REV2'
+                self._mode_utf8()
             else:
                 self.PROTOCOL_VERSION = version
             return
 
         raise self.error('server not IMAP4 compliant')
 
-    def _supports_rev2(self):
-        return 'IMAP4REV2' in self.capabilities
-
-    def _supports_dual_rev1_rev2(self):
-        return self._supports_rev2() and 'IMAP4REV1' in self.capabilities
-
-    def _is_using_rev2(self):
-        return self.PROTOCOL_VERSION == 'IMAP4REV2'
-
     def _is_capability_available(self, capability):
         capability = capability.upper()
-        if self._is_using_rev2() and capability in IMAP4REV2_BUILTIN_COMMANDS:
+        if self.PROTOCOL_VERSION == 'IMAP4REV2' and capability in IMAP4REV2_BUILTIN_COMMANDS:
             return True
         return capability in self.capabilities
 
-    def _should_use_rev1_mode_for_dual_support(self):
-        return self._supports_dual_rev1_rev2()
-
-    def _activate_rev1_mode(self):
-        self.PROTOCOL_VERSION = 'IMAP4REV1'
-        self._mode_ascii()
-
-    def _activate_rev2_mode(self):
-        self.PROTOCOL_VERSION = 'IMAP4REV2'
-        self._mode_utf8()
-
     def _handle_enable_success(self, capability):
         capability = capability.upper()
         if 'UTF8=ACCEPT' in capability:
             self._mode_utf8()
         if 'IMAP4REV2' in capability:
-            self._activate_rev2_mode()
-
+            self.PROTOCOL_VERSION = 'IMAP4REV2'
+            self._mode_utf8()
 
     def __getattr__(self, attr):
         #       Allow UPPERCASE variants of IMAP4 command methods.
@@ -888,7 +870,7 @@ def search(self, charset, *criteria):
         """
         name = 'SEARCH'
         if charset:
-            if self.utf8_enabled and not self._is_using_rev2():
+            if self.utf8_enabled and not self.PROTOCOL_VERSION == 'IMAP4REV2':
                 raise IMAP4.error("Non-None charset not valid in UTF8 mode")
             typ, dat = self._simple_command(name, 'CHARSET', charset, *criteria)
         else:

Lib/test/test_imaplib.py

@@ -138,7 +138,7 @@ def _send_textline(self, message):
     def _send_tagged(self, tag, code, message):
         self._send_textline(' '.join((tag, code, message)))
 
-    def  handle(self):
+    def handle(self):
         # Send a welcome message.
         self._send_textline(f'* OK {self.welcome}')
         while 1:

Misc/NEWS.d/next/Library/2026-05-17-09-42-33.gh-issue-122953.94ShPG.rst

@@ -1,2 +1,2 @@
 Update the :mod:`imaplib` module to support IMAP4rev2 following :rfc:`9501`, with backward compatibility with IMAP4rev1
-(outlined in  :rfc:`9051#appendix-A`) and IMAP4rev1 extensions folded into IMAP4rev2 (outlined in :rfc:`9051#appendix-E`).
+(outlined in  :rfc:`9051#appendix-A`) and IMAP4rev1 extensions folded into IMAP4rev2 (outlined in :rfc:`9051#appendix-E`).