toggle_tab to easily switch to and back from a tab

Fixes #7203

docs/changelog.rst

@@ -73,6 +73,8 @@ Detailed list of changes
 
 - icat kitten: Add a command line argument to override terminal window size detection (:iss:`7165`)
 
+- A new action :ac:`toggle_tab` to easily switch to and back from a tab with a single shortcut (:iss:`7203`)
+
 - When :ac:`clearing terminal <clear_terminal>` add a new type ``to_cursor_scroll`` which can be
   used to clear to prompt while moving cleared lines into the scrollback
 

kitty/options/utils.py

@@ -169,7 +169,7 @@ def detach_tab_parse(func: str, rest: str) -> FuncArgsType:
     return func, (rest,)
 
 
-@func_with_args('set_background_opacity', 'goto_layout', 'toggle_layout', 'kitty_shell', 'show_kitty_doc', 'set_tab_title', 'push_keyboard_mode')
+@func_with_args('set_background_opacity', 'goto_layout', 'toggle_layout', 'toggle_tab', 'kitty_shell', 'show_kitty_doc', 'set_tab_title', 'push_keyboard_mode')
 def simple_parse(func: str, rest: str) -> FuncArgsType:
     return func, [rest]
 

kitty/tabs.py

@@ -7,6 +7,7 @@ import stat
 import weakref
 from collections import deque
 from contextlib import suppress
+from gettext import gettext as _
 from operator import attrgetter
 from time import monotonic
 from typing import (
@@ -870,7 +871,6 @@ class TabManager:  # {{{
         self.wm_class = wm_class
         self.recent_mouse_events: Deque[TabMouseEvent] = deque()
         self.wm_name = wm_name
-        self.last_active_tab_id = None
         self.args = args
         self.tab_bar_hidden = get_options().tab_bar_style == 'hidden'
         self.tabs: List[Tab] = []
@@ -990,6 +990,30 @@ class TabManager:  # {{{
         if len(self.tabs) > 1:
             self.set_active_tab_idx((self.active_tab_idx + len(self.tabs) + delta) % len(self.tabs))
 
+    @ac('win', '''
+        Toggle to the tab matching the specified expression
+
+        Switches to the matching tab if another tab is current, otherwise
+        switches to the last used tab. Useful to easily switch to and back from a
+        tab using a single shortcut. Note that toggling works only between
+        tabs in the same OS window. See :ref:`search_syntax` for details
+        on the match expression. For example::
+
+            map f1 toggle_tab title:mytab
+        ''')
+    def toggle_tab(self, match_expression: str) -> None:
+        tabs = set(get_boss().match_tabs(match_expression)) & set(self)
+        if not tabs:
+            get_boss().show_error(_('No matching tab'), _('No tab found matching the expression: {}').format(match_expression))
+            return
+        if self.active_tab and self.active_tab in tabs:
+            self.goto_tab(-1)
+        else:
+            for x in self:
+                if x in tabs:
+                    self.set_active_tab(x)
+                    break
+
     def tab_at_location(self, loc: str) -> Optional[Tab]:
         if loc == 'prev':
             if self.active_tab_history: