feat(#2127): add experimental.actions.open_file.relative_path to open files with a relative path rather than absolute (#2805)

* temp workaround for issue #2803

* fix #2127 and #2803

* chore(#2127): read the configuration correctly

* feat(#2127): add help

* feat(#2127): normalise relative_path in config hierarchy

* feat(#2127): update help

---------

Co-authored-by: eph <eph@MacBook-Pro.local>
Co-authored-by: Alexander Courtis <alex@courtis.org>

lua/nvim-tree/actions/node/open-file.lua

@@ -190,6 +190,9 @@ local function open_file_in_tab(filename)
   if M.quit_on_open then
     view.close()
   end
+  if M.relative_path then
+    filename = utils.path_relative(filename, vim.fn.getcwd())
+  end
   vim.cmd("tabe " .. vim.fn.fnameescape(filename))
 end
 
@@ -197,6 +200,9 @@ local function drop(filename)
   if M.quit_on_open then
     view.close()
   end
+  if M.relative_path then
+    filename = utils.path_relative(filename, vim.fn.getcwd())
+  end
   vim.cmd("drop " .. vim.fn.fnameescape(filename))
 end
 
@@ -204,6 +210,9 @@ local function tab_drop(filename)
   if M.quit_on_open then
     view.close()
   end
+  if M.relative_path then
+    filename = utils.path_relative(filename, vim.fn.getcwd())
+  end
   vim.cmd("tab :drop " .. vim.fn.fnameescape(filename))
 end
 
@@ -310,7 +319,12 @@ local function open_in_new_window(filename, mode)
     end
   end
 
-  local fname = utils.escape_special_chars(vim.fn.fnameescape(filename))
+  local fname
+  if M.relative_path then
+    fname = utils.escape_special_chars(vim.fn.fnameescape(utils.path_relative(filename, vim.fn.getcwd())))
+  else
+    fname = utils.escape_special_chars(vim.fn.fnameescape(filename))
+  end
 
   local command
   if create_new_window then
@@ -346,6 +360,9 @@ end
 
 local function edit_in_current_buf(filename)
   require("nvim-tree.view").abandon_current_window()
+  if M.relative_path then
+    filename = utils.path_relative(filename, vim.fn.getcwd())
+  end
   vim.cmd("keepalt keepjumps edit " .. vim.fn.fnameescape(filename))
 end
 
@@ -402,6 +419,7 @@ end
 function M.setup(opts)
   M.quit_on_open = opts.actions.open_file.quit_on_open
   M.resize_window = opts.actions.open_file.resize_window
+  M.relative_path = opts.experimental.actions.open_file.relative_path
   if opts.actions.open_file.window_picker.chars then
     opts.actions.open_file.window_picker.chars = tostring(opts.actions.open_file.window_picker.chars):upper()
   end