gh-113951: Tkinter: "tag_unbind(tag, sequence, funcid)" now only unbinds "funcid" (GH-113955)

Previously, "tag_unbind(tag, sequence, funcid)" methods of Text and
Canvas widgets destroyed the current binding for "sequence", leaving
"sequence" unbound, and deleted the "funcid" command.

Now they remove only "funcid" from the binding for "sequence", keeping
other commands, and delete the "funcid" command.
They leave "sequence" unbound only if "funcid" was the last bound command.

1 files changed, 15 insertions, 11 deletions

diff --git a/Lib/tkinter/__init__.py b/Lib/tkinter/__init__.py
index e0db41dd915..a1567d332ae 100644
--- a/Lib/tkinter/__init__.py
+++ b/Lib/tkinter/__init__.py
@@ -1537,16 +1537,19 @@ class Misc:
         Otherwise destroy the current binding for SEQUENCE, leaving SEQUENCE
         unbound.
         """
+        self._unbind(('bind', self._w, sequence), funcid)
+
+    def _unbind(self, what, funcid=None):
         if funcid is None:
-            self.tk.call('bind', self._w, sequence, '')
+            self.tk.call(*what, '')
         else:
-            lines = self.tk.call('bind', self._w, sequence).split('\n')
+            lines = self.tk.call(what).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.tk.call(*what, keep)
             self.deletecommand(funcid)
 
     def bind_all(self, sequence=None, func=None, add=None):
@@ -1558,7 +1561,7 @@ class Misc:
 
     def unbind_all(self, sequence):
         """Unbind for all widgets for event SEQUENCE all functions."""
-        self.tk.call('bind', 'all' , sequence, '')
+        self._root()._unbind(('bind', 'all', sequence))
 
     def bind_class(self, className, sequence=None, func=None, add=None):
         """Bind to widgets with bindtag CLASSNAME at event
@@ -1573,7 +1576,7 @@ class Misc:
     def unbind_class(self, className, sequence):
         """Unbind for all widgets with bindtag CLASSNAME for event SEQUENCE
         all functions."""
-        self.tk.call('bind', className , sequence, '')
+        self._root()._unbind(('bind', className, sequence))
 
     def mainloop(self, n=0):
         """Call the mainloop of Tk."""
@@ -2885,9 +2888,7 @@ class Canvas(Widget, XView, YView):
     def tag_unbind(self, tagOrId, sequence, funcid=None):
         """Unbind for all items with TAGORID for event SEQUENCE  the
         function identified with FUNCID."""
-        self.tk.call(self._w, 'bind', tagOrId, sequence, '')
-        if funcid:
-            self.deletecommand(funcid)
+        self._unbind((self._w, 'bind', tagOrId, sequence), funcid)
 
     def tag_bind(self, tagOrId, sequence=None, func=None, add=None):
         """Bind to all items with TAGORID at event SEQUENCE a call to function FUNC.
@@ -3997,9 +3998,7 @@ class Text(Widget, XView, YView):
     def tag_unbind(self, tagName, sequence, funcid=None):
         """Unbind for all characters with TAGNAME for event SEQUENCE  the
         function identified with FUNCID."""
-        self.tk.call(self._w, 'tag', 'bind', tagName, sequence, '')
-        if funcid:
-            self.deletecommand(funcid)
+        return self._unbind((self._w, 'tag', 'bind', tagName, sequence), funcid)
 
     def tag_bind(self, tagName, sequence, func, add=None):
         """Bind to all characters with TAGNAME at event SEQUENCE a call to function FUNC.
@@ -4010,6 +4009,11 @@ class Text(Widget, XView, YView):
         return self._bind((self._w, 'tag', 'bind', tagName),
                   sequence, func, add)
 
+    def _tag_bind(self, tagName, sequence=None, func=None, add=None):
+        # For tests only
+        return self._bind((self._w, 'tag', 'bind', tagName),
+                  sequence, func, add)
+
     def tag_cget(self, tagName, option):
         """Return the value of OPTION for tag TAGNAME."""
         if option[:1] != '-':