feat: vscode-like path display

All file pickers can be added the option to display paths in vscode
formatting where the filename appears first followed by the directory.

To enable set `formatter="path.filename_first" (hardcoded in globals):
```lua
require("fzf-lua").setup({
  files = {
    formatter = "path.filename_first"
  }
})
```

Can also be sent directly in the call options, e.g:
```lua
:lua require("fzf-lua").live_grep({ formatter = "path.filename_first" })
:FzfLua lsp_finder formatter=path.filename_first
```

This commit also sets up the framework to write your own custom
formatter, if you wish to experiment with that please open an issue.

Ref: #1051

README.md

@@ -803,6 +803,9 @@ require'fzf-lua'.setup {
     file_icons        = true,           -- show file icons?
     color_icons       = true,           -- colorize file|git icons
     -- path_shorten   = 1,              -- 'true' or number, shorten path?
+    -- Uncomment for custom vscode-like formatter where the filename is first:
+    -- e.g. "fzf-lua/previewer/fzf.lua" => "fzf.lua previewer/fzf-lua"
+    -- formatter      = "path.filename_first",
     -- executed command priority is 'cmd' (if exists)
     -- otherwise auto-detect prioritizes `fd`:`rg`:`find`
     -- default options are controlled by 'fd|rg|find|_opts'

lua/fzf-lua/config.lua

@@ -209,6 +209,22 @@ function M.normalize_opts(opts, globals, __resume_key)
       type(M.globals[k]) == "table" and utils.tbl_deep_clone(M.globals[k]) or {})
   end
 
+  -- Setup formatter options
+  if opts.formatter then
+    local _fmt = M.globals["formatters." .. opts.formatter]
+    if _fmt then
+      opts._fmt = opts._fmt or {}
+      opts._fmt.to = opts._fmt.to or _fmt.to
+      opts._fmt.from = opts._fmt.to or _fmt.from
+      -- no support for `bat_native` with a formatter
+      if opts.previewer == "bat_native" then opts.previewer = "bat" end
+      -- no support of searching file begin (we can't guarantee no. of nbsp's)
+      opts._fzf_nth_devicons = false
+    else
+      utils.warn(("Invalid formatter '%s', ignoring."):format(opts.formatter))
+    end
+  end
+
   -- backward compat: no-value flags should be set to `true`, in the past these
   -- would be set to an empty string which would now translate into a shell escaped
   -- string as we automatically shell escape all fzf_opts

lua/fzf-lua/core.lua

@@ -19,7 +19,7 @@ M.ACTION_DEFINITIONS = {
   [actions.toggle_ignore]     = {
     function(o)
       local flag = o.toggle_ignore_flag or "--no-ignore"
-      if o.cmd:match(utils.lua_regex_escape(flag)) then
+      if o.cmd and o.cmd:match(utils.lua_regex_escape(flag)) then
         return "Respect .gitignore"
       else
         return "Disable .gitignore"
@@ -660,6 +660,7 @@ M.mt_cmd_wrapper = function(opts)
       "stdout",
       "stderr",
       "stderr_to_stdout",
+      "formatter",
       "git_dir",
       "git_worktree",
       "git_icons",
@@ -714,7 +715,9 @@ M.mt_cmd_wrapper = function(opts)
       and not opts.git_icons
       and not opts.file_icons
       and not opts.file_ignore_patterns
-      and not opts.path_shorten then
+      and not opts.path_shorten
+      and not opts.formatter
+  then
     -- command does not require any processing, we also reset `argv_expr`
     -- to keep `setup_fzf_interactive_flags::no_query_condi` in the command
     opts.argv_expr = nil

lua/fzf-lua/defaults.lua

@@ -193,6 +193,35 @@ M.defaults                      = {
       pager     = M._preview_pager_fn,
     },
   },
+  formatters    = {
+    path = {
+      filename_first = {
+        -- NOT NEEDED: for perf reasons we format at the source in `make_entry.file`
+        -- to = function(s, _)
+        -- end,
+        from = function(s, o)
+          -- Which part should contain the parent folder?
+          -- files that are directly under cwd it will have no parent folder part
+          local parent_idx = (o._parent_idx or 2)
+              + (o.file_icons and 1 or 0)
+              + (o.git_icons and 1 or 0)
+          local parts = utils.strsplit(s, utils.nbsp)
+          if #parts == parent_idx then
+            local last = parts[parent_idx]
+            local filename = parts[parent_idx - 1]
+            local parent = last:match("^[^:]+")
+            local fullpath = path.join({ parent, filename })
+            -- remove the last part (parent + rest of line)
+            table.remove(parts, parent_idx)
+            -- overwrite last part with restored fullpath + rest of line
+            parts[#parts] = fullpath .. last:sub(#parent + 1)
+            s = table.concat(parts, utils.nbsp)
+          end
+          return s
+        end
+      }
+    }
+  },
 }
 
 M.defaults.files                = {

lua/fzf-lua/make_entry.lua

@@ -331,7 +331,7 @@ M.file = function(x, opts)
   if opts.git_icons then
     local diff_info = opts.diff_files
         and opts.diff_files[utils._if_win(path.normalize(origpath), origpath)]
-    local indicators = diff_info and diff_info[1] or utils.nbsp
+    local indicators = diff_info and diff_info[1] or " "
     for i = 1, #indicators do
       icon = indicators:sub(i, i)
       local git_icon = config.globals.git.icons[icon]
@@ -355,10 +355,27 @@ M.file = function(x, opts)
     ret[#ret + 1] = icon
     ret[#ret + 1] = utils.nbsp
   end
-  ret[#ret + 1] = file_is_ansi > 0
-      -- filename is ansi escape colored, replace the inner string (#819)
-      and file_part:gsub(utils.lua_regex_escape(stripped_filepath), filepath)
-      or filepath
+  -- convert to number type for faster condition testing next entry
+  if opts.formatter == "path.filename_first" then
+    opts.formatter = 1
+  end
+  if tonumber(opts.formatter) == 1 then
+    -- skip ansi coloring restoration as we use our own hlgroup for the parent
+    local parent = path.parent(filepath)
+    if parent then
+      ret[#ret + 1] = path.tail(filepath)
+      ret[#ret + 1] = utils.nbsp
+      ret[#ret + 1] = utils.ansi_codes.grey(path.remove_trailing(parent))
+      -- ret[#ret + 1] = path.remove_trailing(parent)
+    else
+      ret[#ret + 1] = filepath
+    end
+  else
+    ret[#ret + 1] = file_is_ansi > 0
+        -- filename is ansi escape colored, replace the inner string (#819)
+        and file_part:gsub(utils.lua_regex_escape(stripped_filepath), filepath)
+        or filepath
+  end
   ret[#ret + 1] = rest_of_line
   return table.concat(ret)
 end

lua/fzf-lua/providers/git.lua

@@ -44,6 +44,9 @@ M.status = function(opts)
   -- as part of our `git status -s`
   opts.git_icons = false
 
+  -- set parent_idx base for `formatter=path.filename_first`
+  opts._parent_idx = 5
+
   -- we always require processing (can't send the raw command to fzf)
   opts.requires_processing = true
 

lua/fzf-lua/providers/lsp.lua

@@ -665,6 +665,8 @@ M.finder = function(opts)
     return
   end
   opts = core.set_fzf_field_index(opts)
+  -- set parent_idx base for `formatter=path.filename_first`
+  opts._parent_idx = 3
   return core.fzf_exec(contents, opts)
 end