Allow passing a `!neighbor` argument to the new_window mapping to open a new window next to the active window

Fixes #1746

docs/changelog.rst

@@ -9,6 +9,9 @@ To update |kitty|, :doc:`follow the instructions <binary>`.
 
 - Remote control: Add a command `kitty @ scroll-window` to scroll windows
 
+- Allow passing a ``!neighbor`` argument to the new_window mapping to open a
+  new window next to the active window (:iss:`1746`)
+
 - Fix an out of bounds read causing a crash when selecting text with the mouse
   in the alternate screen mode (:iss:`1578`)
 

kitty/boss.py

@@ -988,10 +988,14 @@ class Boss:
     def _new_window(self, args, cwd_from=None):
         tab = self.active_tab
         if tab is not None:
+            location = None
+            if args and args[0].startswith('!'):
+                location = args[0][1:].lower()
+                args = args[1:]
             if args:
-                return tab.new_special_window(self.args_to_special_window(args, cwd_from=cwd_from))
+                return tab.new_special_window(self.args_to_special_window(args, cwd_from=cwd_from), location=location)
             else:
-                return tab.new_window(cwd_from=cwd_from)
+                return tab.new_window(cwd_from=cwd_from, location=location)
 
     def new_window(self, *args):
         self._new_window(args)

kitty/config_data.py

@@ -1066,6 +1066,13 @@ Any programs running in that window will be allowed to control kitty.
 For example::
 
     map ctrl+enter new_window @ some_program
+
+You can open a new window next to the currently active window or as the first window,
+with::
+
+    map ctrl+n new_window !neighbor some_program
+    map ctrl+f new_window !first some_program
+
 '''))
 if is_macos:
     k('new_window', 'cmd+enter', 'new_window', _('New window'), add_to_docs=False)

kitty/layout.py

@@ -267,7 +267,7 @@ class Layout:  # {{{
         self.swap_windows_in_os_window(nidx, idx)
         return self.set_active_window(all_windows, nidx)
 
-    def add_window(self, all_windows, window, current_active_window_idx):
+    def add_window(self, all_windows, window, current_active_window_idx, location=None):
         active_window_idx = None
         if window.overlay_for is not None:
             i = idx_for_id(window.overlay_for, all_windows)
@@ -278,6 +278,16 @@ class Layout:  # {{{
                 all_windows.append(all_windows[i])
                 all_windows[i] = window
                 active_window_idx = i
+        elif location is not None:
+            if location == 'neighbor' and current_active_window_idx is not None:
+                active_window_idx = current_active_window_idx + 1
+            elif location == 'first':
+                active_window_idx = 0
+            if active_window_idx is not None:
+                for i in range(len(all_windows), active_window_idx, -1):
+                    self.swap_windows_in_os_window(i, i - 1)
+                all_windows.insert(active_window_idx, window)
+
         if active_window_idx is None:
             active_window_idx = len(all_windows)
             all_windows.append(window)

kitty/tabs.py

@@ -232,7 +232,7 @@ class Tab:  # {{{
         ans.fork()
         return ans
 
-    def new_window(self, use_shell=True, cmd=None, stdin=None, override_title=None, cwd_from=None, cwd=None, overlay_for=None, env=None):
+    def new_window(self, use_shell=True, cmd=None, stdin=None, override_title=None, cwd_from=None, cwd=None, overlay_for=None, env=None, location=None):
         child = self.launch_child(use_shell=use_shell, cmd=cmd, stdin=stdin, cwd_from=cwd_from, cwd=cwd, env=env)
         window = Window(self, child, self.opts, self.args, override_title=override_title)
         if overlay_for is not None:
@@ -241,12 +241,12 @@ class Tab:  # {{{
             overlaid.overlay_window_id = window.id
         # Must add child before laying out so that resize_pty succeeds
         get_boss().add_child(window)
-        self.active_window_idx = self.current_layout.add_window(self.windows, window, self.active_window_idx)
+        self.active_window_idx = self.current_layout.add_window(self.windows, window, self.active_window_idx, location)
         self.relayout_borders()
         return window
 
-    def new_special_window(self, special_window):
-        return self.new_window(False, *special_window)
+    def new_special_window(self, special_window, location=None):
+        return self.new_window(False, *special_window, location=location)
 
     def close_window(self):
         if self.windows: