Merge pull request #33 from mrjones2014/mrj/32/check-tmux-session

check tmux session before attempting to change tmux panes

lua/smart-splits/tmux.lua

@@ -1,11 +1,30 @@
 local M = {}
 
+local function get_socket_path()
+  local tmux = vim.env.TMUX
+  if not tmux or #tmux == 0 then
+    return nil
+  end
+
+  return vim.split(tmux, ',')[1]
+end
+
+local function tmux_exec(cmd)
+  local socket = get_socket_path()
+  if not socket then
+    return nil
+  end
+
+  local cmd_str = string.format('tmux -S %s %s', socket, cmd)
+  return vim.fn.system(cmd_str)
+end
+
 ---Try to get current tmux pane ID
----returns nil if failed.
+---returns nil if failed or not in a tmux session.
 ---@return string|nil
 function M.current_pane_id()
   local _, id = pcall(function()
-    local output = vim.fn.system('tmux display-message -p "#{pane_id}"')
+    local output = tmux_exec('display-message -p "#{pane_id}"')
     if not output or #output == 0 then
       return nil
     end
@@ -23,7 +42,7 @@ end
 function M.next_pane(direction)
   direction = string.upper(direction)
   local ok, _ = pcall(function()
-    vim.fn.system(string.format('tmux select-pane -%s', direction))
+    tmux_exec(string.format('select-pane -%s', direction))
   end)
 
   return ok