From 360d15a87081d87ffdcdaa173714f8be028c1a17 Mon Sep 17 00:00:00 2001
From: Serhiy Storchaka <storchaka@gmail.com>
Date: Wed, 6 Dec 2023 16:42:15 +0200
Subject: [PATCH] gh-75666: Tkinter: "unbind(sequence, funcid)" now only
 unbinds "funcid" (GH-111322)

Previously, "widget.unbind(sequence, funcid)" destroyed the current binding
for "sequence", leaving "sequence" unbound, and deleted the "funcid"
command.

Now it removes only "funcid" from the binding for "sequence", keeping
other commands, and deletes the "funcid" command.
It leaves "sequence" unbound only if "funcid" was the last bound command.

Co-authored-by: GiovanniL <13402461+GiovaLomba@users.noreply.github.com>
---
 Lib/test/test_tkinter/test_misc.py            | 34 +++++++++++++++----
 Lib/tkinter/__init__.py                       | 22 +++++++++---
 ...3-10-25-16-37-13.gh-issue-75666.BpsWut.rst |  6 ++++
 3 files changed, 51 insertions(+), 11 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2023-10-25-16-37-13.gh-issue-75666.BpsWut.rst

diff --git a/Lib/test/test_tkinter/test_misc.py b/Lib/test/test_tkinter/test_misc.py
index ca99caaf88b80dd..6639eaaa59936a9 100644
--- a/Lib/test/test_tkinter/test_misc.py
+++ b/Lib/test/test_tkinter/test_misc.py
@@ -479,26 +479,46 @@ def test2(e): pass
 
     def test_unbind2(self):
         f = self.frame
+        f.wait_visibility()
+        f.focus_force()
+        f.update_idletasks()
         event = '<Control-Alt-Key-c>'
         self.assertEqual(f.bind(), ())
         self.assertEqual(f.bind(event), '')
-        def test1(e): pass
-        def test2(e): pass
+        def test1(e): events.append('a')
+        def test2(e): events.append('b')
+        def test3(e): events.append('c')
 
         funcid = f.bind(event, test1)
         funcid2 = f.bind(event, test2, add=True)
+        funcid3 = f.bind(event, test3, add=True)
+        events = []
+        f.event_generate(event)
+        self.assertEqual(events, ['a', 'b', 'c'])
 
-        f.unbind(event, funcid)
+        f.unbind(event, funcid2)
         script = f.bind(event)
-        self.assertNotIn(funcid, script)
-        self.assertCommandNotExist(funcid)
-        self.assertCommandExist(funcid2)
+        self.assertNotIn(funcid2, script)
+        self.assertIn(funcid, script)
+        self.assertIn(funcid3, script)
+        self.assertEqual(f.bind(), (event,))
+        self.assertCommandNotExist(funcid2)
+        self.assertCommandExist(funcid)
+        self.assertCommandExist(funcid3)
+        events = []
+        f.event_generate(event)
+        self.assertEqual(events, ['a', 'c'])
 
-        f.unbind(event, funcid2)
+        f.unbind(event, funcid)
+        f.unbind(event, funcid3)
         self.assertEqual(f.bind(event), '')
         self.assertEqual(f.bind(), ())
         self.assertCommandNotExist(funcid)
         self.assertCommandNotExist(funcid2)
+        self.assertCommandNotExist(funcid3)
+        events = []
+        f.event_generate(event)
+        self.assertEqual(events, [])
 
         # non-idempotent
         self.assertRaises(tkinter.TclError, f.unbind, event, funcid2)
diff --git a/Lib/tkinter/__init__.py b/Lib/tkinter/__init__.py
index 0df7f9d889413c8..124882420c255c3 100644
--- a/Lib/tkinter/__init__.py
+++ b/Lib/tkinter/__init__.py
@@ -1527,10 +1527,24 @@ def bind(self, sequence=None, func=None, add=None):
         return self._bind(('bind', self._w), sequence, func, add)
 
     def unbind(self, sequence, funcid=None):
-        """Unbind for this widget for event SEQUENCE  the
-        function identified with FUNCID."""
-        self.tk.call('bind', self._w, sequence, '')
-        if funcid:
+        """Unbind for this widget the event SEQUENCE.
+
+        If FUNCID is given, only unbind the function identified with FUNCID
+        and also delete the corresponding Tcl command.
+
+        Otherwise destroy the current binding for SEQUENCE, leaving SEQUENCE
+        unbound.
+        """
+        if funcid is None:
+            self.tk.call('bind', self._w, sequence, '')
+        else:
+            lines = self.tk.call('bind', self._w, sequence).split('\n')
+            prefix = f'if {{"[{funcid} '
+            keep = '\n'.join(line for line in lines
+                             if not line.startswith(prefix))
+            if not keep.strip():
+                keep = ''
+            self.tk.call('bind', self._w, sequence, keep)
             self.deletecommand(funcid)
 
     def bind_all(self, sequence=None, func=None, add=None):
diff --git a/Misc/NEWS.d/next/Library/2023-10-25-16-37-13.gh-issue-75666.BpsWut.rst b/Misc/NEWS.d/next/Library/2023-10-25-16-37-13.gh-issue-75666.BpsWut.rst
new file mode 100644
index 000000000000000..d774cc4f7c687f2
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-10-25-16-37-13.gh-issue-75666.BpsWut.rst
@@ -0,0 +1,6 @@
+Fix the behavior of :mod:`tkinter` widget's ``unbind()`` method with two
+arguments. Previously, ``widget.unbind(sequence, funcid)`` destroyed the
+current binding for *sequence*, leaving *sequence* unbound, and deleted the
+*funcid* command. Now it removes only *funcid* from the binding for
+*sequence*, keeping other commands, and deletes the *funcid* command. It
+leaves *sequence* unbound only if *funcid* was the last bound command.