Feature: collapse directories (#65)

When enabled/toggled, directories that only contain another directory will be displayed like `a/b/c/`, allowing you to navigate more quickly down the filesystem

---------

Co-authored-by: Simon McLean <simonmclean@192.168.1.116>
Co-authored-by: simonmclean <simonmclean@users.noreply.github.com>
Co-authored-by: Simon McLean <simonmclean@192.168.1.129>

README.md

@@ -96,11 +96,13 @@ require 'triptych'.setup {
     paste = 'p',
     quit = 'q',
     toggle_hidden = '<leader>.',
+    toggle_collapse_dirs = 'z',
   },
   extension_mappings = {},
   options = {
     dirs_first = true,
     show_hidden = false,
+    collapse_dirs = true,
     line_numbers = {
       enabled = true,
       relative = false,

doc/triptych.nvim.txt

@@ -104,11 +104,13 @@ bindings.
         paste = 'p',
         quit = 'q',
         toggle_hidden = '<leader>.',
+        toggle_collapse_dirs = 'z',
       },
       extension_mappings = {},
       options = {
         dirs_first = true,
         show_hidden = false,
+        collapse_dirs = true,
         line_numbers = {
           enabled = true,
           relative = false,

lua/triptych/actions.lua

@@ -365,11 +365,13 @@ function Actions.new(State, refresh_view)
 
   ---@return nil
   M.toggle_hidden = function()
-    if State.show_hidden then
-      State.show_hidden = false
-    else
-      State.show_hidden = true
-    end
+    State.show_hidden = not State.show_hidden
+    refresh_view()
+  end
+
+  ---@return nil
+  M.toggle_collapse_dirs = function()
+    State.collapse_dirs = not State.collapse_dirs
     refresh_view()
   end
 
@@ -396,7 +398,15 @@ function Actions.new(State, refresh_view)
     local target = view.get_target_under_cursor(State)
     if target then
       if target.is_dir then
-        view.set_primary_and_parent_window_targets(State, target.path)
+        local target_path
+        if State.collapse_dirs and target.collapse_path then
+          target_path = target.collapse_path
+        else
+          target_path = target.path
+        end
+        if target_path then
+          view.set_primary_and_parent_window_targets(State, target_path)
+        end
       else
         edit_file(target.path, 'in-place')
       end

lua/triptych/config.lua

@@ -6,6 +6,93 @@ local function config_warn(config_prop_name)
   end
 end
 
+---@class TriptychConfig
+---@field debug boolean
+---@field mappings TriptychConfigMappings
+---@field extension_mappings { [string]: ExtensionMapping }
+---@field options TriptychConfigOptions
+---@field git_signs TriptychConfigGitSigns
+---@field diagnostic_signs TriptychConfigDiagnostic
+
+---@class TriptychConfigMappings
+---@field show_help KeyMapping
+---@field jump_to_cwd KeyMapping
+---@field nav_left KeyMapping
+---@field nav_right KeyMapping
+---@field open_vsplit KeyMapping
+---@field open_hsplit KeyMapping
+---@field open_tab KeyMapping
+---@field cd KeyMapping
+---@field delete KeyMapping
+---@field add KeyMapping
+---@field copy KeyMapping
+---@field rename KeyMapping
+---@field cut KeyMapping
+---@field paste KeyMapping
+---@field quit KeyMapping
+---@field toggle_hidden KeyMapping
+---@field toggle_collapse_dirs KeyMapping
+
+---@class ExtensionMapping
+---@field mode string
+---@field fn fun(contents?: PathDetails, refresh_fn: fun(): nil): nil
+
+---@class TriptychConfigOptions
+---@field dirs_first boolean
+---@field collapse_dirs boolean
+---@field show_hidden boolean
+---@field line_numbers TriptychConfigLineNumbers
+---@field file_icons TriptychConfigFileIcons
+---@field responsive_column_widths { [string]: number[] }
+---@field highlights TriptychConfigHighlights
+---@field syntax_highlighting TriptychConfigSyntaxHighlighting
+---@field backdrop number
+---@field border string | table
+---@field max_height number
+---@field max_width number
+---@field margin_x number
+---@field margin_y number
+
+---@class TriptychConfigHighlights
+---@field file_names string
+---@field directory_names string
+
+---@class TriptychConfigSyntaxHighlighting
+---@field enabled boolean
+---@field debounce_ms number
+
+---@class TriptychConfigLineNumbers
+---@field enabled boolean
+---@field relative boolean
+
+---@class TriptychConfigFileIcons
+---@field enabled boolean
+---@field directory_icon string
+---@field fallback_file_icon  string
+
+---@class TriptychConfigGitSigns
+---@field enabled boolean
+---@field signs TriptychConfigGitSignsSigns
+
+---@class TriptychConfigGitSignsSigns
+---@field add string | TriptychConfigGitSignDefineOptions
+---@field modify string | TriptychConfigGitSignDefineOptions
+---@field rename string | TriptychConfigGitSignDefineOptions
+---@field untracked string | TriptychConfigGitSignDefineOptions
+
+---@class TriptychConfigGitSignDefineOptions
+---@field icon? string
+---@field linehl? string
+---@field numhl? string
+---@field text? string
+---@field texthl? string
+---@field culhl? string
+
+---@class TriptychConfigDiagnostic
+---@field enabled boolean
+
+---@alias KeyMapping (string | string[])
+
 ---@return TriptychConfig
 local function default_config()
   return {
@@ -28,10 +115,12 @@ local function default_config()
       paste = 'p',
       quit = 'q',
       toggle_hidden = '<leader>.',
+      toggle_collapse_dirs = 'z',
     },
     extension_mappings = {},
     options = {
       dirs_first = true,
+      collapse_dirs = true,
       show_hidden = false,
       line_numbers = {
         enabled = true,

lua/triptych/event_handlers.lua

@@ -3,6 +3,7 @@ local log = require 'triptych.logger'
 local float = require 'triptych.float'
 local autocmds = require 'triptych.autocmds'
 local view = require 'triptych.view'
+local fs = require 'triptych.fs'
 
 local M = {}
 
@@ -16,7 +17,13 @@ function M.handle_cursor_moved(State)
   local line_number = vim.api.nvim_win_get_cursor(0)[1]
   State.path_to_line_map[current_dir] = line_number
   if target then
-    view.set_child_window_target(State, target)
+    local final_target
+    if State.collapse_dirs and target.is_dir and target.collapse_path then
+      final_target = fs.read_path(target.collapse_path, true)
+    else
+      final_target = target
+    end
+    view.set_child_window_target(State, final_target)
   end
 end
 

lua/triptych/fs.lua

@@ -38,10 +38,37 @@ M.read_file_async = plenary_async.wrap(function(file_path, callback)
   end)
 end, 2)
 
+---Keep recursively reading into sub-directories, so long as each sub-directory contains only a single directory and no files
+---@param path string
+---@param display_name string
+---@return string - full path
+---@return string - display name
+local function read_collapsed_dirs(path, display_name)
+  local handle, _ = vim.loop.fs_scandir(path)
+  if not handle then
+    return path, display_name
+  end
+
+  local first_node_name, first_node_type = vim.loop.fs_scandir_next(handle)
+
+  -- Empty dir, or node is not a directory
+  if not first_node_name or first_node_type ~= 'directory' then
+    return path, display_name
+  end
+
+  local second_node_name, _ = vim.loop.fs_scandir_next(handle)
+
+  -- Directory contains more than 1 node
+  if second_node_name then
+    return path, display_name
+  end
+
+  return read_collapsed_dirs(path .. '/' .. first_node_name, display_name .. first_node_name .. '/')
+end
+
 ---@param _path string
----@param show_hidden boolean
----@param callback fun(path_details: PathDetails): nil
-function M.get_path_details(_path, show_hidden, callback)
+---@param include_collapsed boolean whether to drill recursively into collapsed dirs
+function M.read_path(_path, include_collapsed)
   local path = vim.fs.normalize(_path)
 
   local tree = {
@@ -56,8 +83,7 @@ function M.get_path_details(_path, show_hidden, callback)
   local handle, _ = vim.loop.fs_scandir(path)
   if not handle then
     -- On error fallback to cwd
-    M.get_path_details(vim.fn.getcwd(), show_hidden, callback)
-    return
+    return M.read_path(vim.fn.getcwd())
   end
 
   while true do
@@ -66,24 +92,27 @@ function M.get_path_details(_path, show_hidden, callback)
       break
     end
     local entry_path = path .. '/' .. name
-    table.insert(tree.children, {
-      display_name = u.eval(function()
-        if type == 'directory' then
-          return name .. '/'
-        end
-        return name
-      end),
+    local is_dir = type == 'directory'
+    local display_name = is_dir and (name .. '/') or name
+    local entry = {
+      display_name = display_name,
       path = entry_path,
       dirname = path,
-      is_dir = type == 'directory',
+      is_dir = is_dir,
       filetype = u.eval(function()
         if type == 'directory' then
           return
         end
         return M.get_filetype_from_path(entry_path)
       end),
       children = {},
-    })
+    }
+    if is_dir and include_collapsed then
+      local collapsed_path, collapsed_display_name = read_collapsed_dirs(entry_path, display_name)
+      entry.collapse_path = collapsed_path
+      entry.collapse_display_name = collapsed_display_name
+    end
+    table.insert(tree.children, entry)
   end
 
   if vim.g.triptych_config.options.dirs_first then
@@ -98,7 +127,7 @@ function M.get_path_details(_path, show_hidden, callback)
     end)
   end
 
-  callback(tree)
+  return tree
 end
 
 return M

lua/triptych/mappings.lua

@@ -44,6 +44,7 @@ function Mappings.new(State, actions, refresh_fn)
   map('n', mappings.paste, actions.paste)
   map('n', mappings.show_help, actions.help)
   map('n', mappings.toggle_hidden, actions.toggle_hidden)
+  map('n', mappings.toggle_collapse_dirs, actions.toggle_collapse_dirs)
   map('n', mappings.quit, function()
     vim.g.triptych_close() -- TODO: Move to actions
   end)

lua/triptych/state.lua

@@ -1,5 +1,20 @@
 local u = require 'triptych.utils'
 
+---@class TriptychState
+---@field new fun(config: TriptychConfig, opening_win: integer): TriptychState
+---@field list_add fun(self: TriptychState, list_type: 'cut' | 'copy', item: PathDetails): nil
+---@field list_remove fun(self: TriptychState, list_type: 'cut' | 'copy', item: PathDetails): nil
+---@field list_remove_all fun(self: TriptychState, list_type: 'cut' | 'copy'): nil
+---@field list_toggle fun(self: TriptychState, list_type: 'cut' | 'copy', item: PathDetails): nil
+---@field list_contains fun(self: TriptychState, list_type: 'cut' | 'copy', item: PathDetails): nil
+---@field windows ViewState
+---@field cut_list PathDetails[]
+---@field copy_list PathDetails[]
+---@field path_to_line_map { [string]: integer }
+---@field opening_win integer
+---@field show_hidden boolean
+---@field collapse_dirs boolean
+---@field has_initial_cursor_pos_been_set boolean
 local TriptychState = {}
 
 ---@return TriptychState
@@ -8,6 +23,7 @@ function TriptychState.new(config, opening_win)
   setmetatable(instance, { __index = TriptychState })
 
   instance.show_hidden = config.options.show_hidden
+  instance.collapse_dirs = config.options.collapse_dirs
   instance.windows = {
     parent = {
       path = '',