perf: Improve startup by droping most of the requires + refactors

Important: It's no longer guaranteed that if component/extension
of same name exists in multiple entries in rtp which one will be
loaded. The guarantee is still there for themes . Means other
plugins or users config can overwrite a lualines internal theme
with same file name . I'm droping the guarantee for components
and extensions because there isn't much usecase for it . It's simple
to have a unique name and droping that guarantee allows more
optimizations that speeds up lualine.

lua/lualine/components/diagnostics.lua

@@ -1,12 +1,13 @@
 -- Copyright (c) 2020-2021 hoob3rt
 -- MIT license, see LICENSE for more details.
-local modules = require('lualine.utils.lazy_require'){
+local lualine_require = require'lualine_require'
+local modules = lualine_require.lazy_require{
   highlight = 'lualine.highlight',
   utils = 'lualine.utils.utils',
   utils_notices = 'lualine.utils.notices',
 }
 
-local Diagnostics = require('lualine.component'):new()
+local Diagnostics = lualine_require.require('lualine.component'):new()
 
 -- LuaFormatter off
 Diagnostics.default_colors = {

lua/lualine/components/diff.lua

@@ -1,11 +1,14 @@
 -- Copyright (c) 2020-2021 shadmansaleh
 -- MIT license, see LICENSE for more details.
-local utils = require 'lualine.utils.utils'
-local utils_notices = require('lualine.utils.notices')
-local highlight = require 'lualine.highlight'
-local Job = require'lualine.utils.job'
 
-local Diff = require('lualine.component'):new()
+local lualine_require = require'lualine_require'
+local modules = lualine_require.lazy_require{
+  utils         = 'lualine.utils.utils',
+  utils_notices = 'lualine.utils.notices',
+  highlight     = 'lualine.highlight',
+  Job           = 'lualine.utils.job',
+}
+local Diff = lualine_require.require('lualine.component'):new()
 
 -- Vars
 -- variable to store git diff stats
@@ -25,7 +28,7 @@ Diff.default_colors = {
 local diff_cache = {} -- Stores last known value of diff of a buffer
 
 local function color_deprecation_notice(color, opt_name)
-  utils_notices.add_notice(string.format([[
+  modules.utils_notices.add_notice(string.format([[
 ### Diff component
 Using option `%s` as string to set foreground color has been deprecated
 and will soon be removed. Now this option has same semantics as regular
@@ -64,7 +67,7 @@ Diff.new = function(self, options, child)
   -- apply colors
   if not new_instance.options.color_added then
     new_instance.options.color_added = {fg =
-      utils.extract_highlight_colors('DiffAdd', 'fg') or
+      modules.utils.extract_highlight_colors('DiffAdd', 'fg') or
           Diff.default_colors.added}
   elseif type(new_instance.options.color_added) == 'string'
     and vim.fn.hlexists(new_instance.options.color_added) == 0 then
@@ -73,7 +76,7 @@ Diff.new = function(self, options, child)
   end
   if not new_instance.options.color_modified then
     new_instance.options.color_modified = {fg =
-        utils.extract_highlight_colors('DiffChange', 'fg') or
+        modules.utils.extract_highlight_colors('DiffChange', 'fg') or
             Diff.default_colors.modified}
   elseif type(new_instance.options.color_modified) == 'string'
     and vim.fn.hlexists(new_instance.options.color_modified) == 0 then
@@ -82,7 +85,7 @@ Diff.new = function(self, options, child)
   end
   if not new_instance.options.color_removed then
     new_instance.options.color_removed = {fg =
-        utils.extract_highlight_colors('DiffDelete', 'fg') or
+        modules.utils.extract_highlight_colors('DiffDelete', 'fg') or
             Diff.default_colors.removed}
   elseif type(new_instance.options.color_removed) == 'string'
     and vim.fn.hlexists(new_instance.options.color_removed) == 0 then
@@ -93,13 +96,13 @@ Diff.new = function(self, options, child)
   -- create highlights and save highlight_name in highlights table
   if new_instance.options.colored then
     new_instance.highlights = {
-      added = highlight.create_component_highlight_group(
+      added = modules.highlight.create_component_highlight_group(
           new_instance.options.color_added, 'diff_added',
           new_instance.options),
-      modified = highlight.create_component_highlight_group(
+      modified = modules.highlight.create_component_highlight_group(
           new_instance.options.color_modified, 'diff_modified',
           new_instance.options),
-      removed = highlight.create_component_highlight_group(
+      removed = modules.highlight.create_component_highlight_group(
           new_instance.options.color_removed, 'diff_removed',
           new_instance.options)
     }
@@ -109,7 +112,7 @@ Diff.new = function(self, options, child)
 
   if Diff.diff_checker_enabled then
     -- setup internal source
-    utils.define_autocmd('BufWritePost', "lua require'lualine.components.diff'.update_git_diff()")
+    modules.utils.define_autocmd('BufWritePost', "lua require'lualine.components.diff'.update_git_diff()")
     Diff.update_diff_args()
   end
 
@@ -136,7 +139,7 @@ Diff.update_status = function(self, is_focused)
   if self.options.colored then
     -- load the highlights and store them in colors table
     for name, highlight_name in pairs(self.highlights) do
-      colors[name] = highlight.component_format_highlight(highlight_name)
+      colors[name] = modules.highlight.component_format_highlight(highlight_name)
     end
   end
 
@@ -242,7 +245,7 @@ function Diff.update_git_diff()
   if Diff.diff_args then
     Diff.diff_output_cache = {}
     if Diff.diff_job then Diff.diff_job:stop() end
-    Diff.diff_job = Job(Diff.diff_args)
+    Diff.diff_job = modules.Job(Diff.diff_args)
     if Diff.diff_job then Diff.diff_job:start() end
   end
 end

lua/lualine/components/filetype.lua

@@ -1,9 +1,11 @@
 -- Copyright (c) 2020-2021 hoob3rt
 -- MIT license, see LICENSE for more details.
-local highlight = require('lualine.highlight')
+local lualine_require = require'lualine_require'
-local utils = require('lualine.utils.utils')
+local modules = lualine_require.lazy_require{
-
+  highlight = 'lualine.highlight',
-local FileType = require('lualine.component'):new()
+  utils     = 'lualine.utils.utils',
+}
+local FileType = lualine_require.require('lualine.component'):new()
 
 function FileType:new(options, child)
   local new_instance = self._parent:new(options, child or FileType)
@@ -28,21 +30,21 @@ function FileType:apply_icon()
     icon, icon_highlight_group = devicons.get_icon(f_name, f_extension)
 
     if icon and self.options.colored then
-      local highlight_color = utils.extract_highlight_colors(
+      local highlight_color = modules.utils.extract_highlight_colors(
                                   icon_highlight_group, 'fg')
-      local is_focused = utils.is_focused()
+      local is_focused = modules.utils.is_focused()
-      local default_highlight = highlight.format_highlight(is_focused,
+      local default_highlight = modules.highlight.format_highlight(is_focused,
                                                            self.options.self
                                                                .section)
       local icon_highlight = self.options.self.section .. '_' ..
                                  icon_highlight_group
-      if not utils.highlight_exists(icon_highlight .. '_normal') then
+      if not modules.utils.highlight_exists(icon_highlight .. '_normal') then
-        icon_highlight = highlight.create_component_highlight_group(
+        icon_highlight = modules.highlight.create_component_highlight_group(
                              {fg = highlight_color}, icon_highlight_group,
                              self.options)
       end
 
-      icon = highlight.component_format_highlight(icon_highlight) .. icon ..
+      icon = modules.highlight.component_format_highlight(icon_highlight) .. icon ..
                  default_highlight
     end
   else

lua/lualine/components/mode.lua

@@ -1,5 +1,6 @@
 -- Copyright (c) 2020-2021 hoob3rt
 -- MIT license, see LICENSE for more details.
+local require = require'lualine_require'.require
 local Mode = require('lualine.component'):new()
 local get_mode = require('lualine.utils.mode').get_mode
 

lua/lualine/highlight.lua

@@ -1,22 +1,25 @@
 -- Copyright (c) 2020-2021 hoob3rt
 -- MIT license, see LICENSE for more details.
 local M = {}
-local cterm_colors
+local lualine_require = require'lualine_require'
-local utils = require 'lualine.utils.utils'
+local require = lualine_require.require
+local modules = lualine_require.lazy_require{
+  utils = 'lualine.utils.utils',
+  color_utils = 'lualine.utils.cterm_colors',
+}
 local section_highlight_map = {x = 'c', y = 'b', z = 'a'}
 local active_theme = nil
+local create_cterm_colors = false
 
 local function sanitize_color(color)
   if type(color) == 'string' then
     if color:sub(1,1) == '#' then return color end -- RGB value
-    local converter = require 'lualine.utils.cterm_colors'
+    return modules.color_utils.color_name2rgb(color)
-    return converter.color_name2rgb(color)
   elseif type(color) == 'number' then
     if color > 255 then
       error("What's this it can't be higher then 255 and you've given "..color)
     end
-    local converter = require 'lualine.utils.cterm_colors'
+    return modules.color_utils.cterm2rgb(color)
-    return converter.cterm2rgb(color)
   end
 end
 
@@ -30,16 +33,16 @@ function M.highlight(name, foreground, background, gui, link, reload)
     table.insert(command, name)
     if foreground and foreground ~= 'none' then
       table.insert(command, 'guifg=' .. foreground)
-      if cterm_colors then
+      if create_cterm_colors then
         table.insert(command,
-                     'ctermfg=' .. cterm_colors.get_cterm_color(foreground))
+                     'ctermfg=' .. modules.color_utils.get_cterm_color(foreground))
       end
     end
     if background and background ~= 'none' then
       table.insert(command, 'guibg=' .. background)
-      if cterm_colors then
+      if create_cterm_colors then
         table.insert(command,
-                     'ctermbg=' .. cterm_colors.get_cterm_color(background))
+                     'ctermbg=' .. modules.color_utils.get_cterm_color(background))
       end
     end
     if gui then
@@ -49,15 +52,15 @@ function M.highlight(name, foreground, background, gui, link, reload)
   end
   vim.cmd(table.concat(command, ' '))
   if not reload then
-    utils.save_highlight(name, {name, foreground, background, gui, link, true})
+    modules.utils.save_highlight(name, {name, foreground, background, gui, link, true})
   end
 end
 
 function M.create_highlight_groups(theme)
-  utils.clear_highlights()
+  modules.utils.clear_highlights()
   active_theme = theme
-  if not vim.opt.termguicolors:get() then
+  if not vim.go.termguicolors then
-    cterm_colors = require 'lualine.utils.cterm_colors'
+    create_cterm_colors = true
   end
   for mode, sections in pairs(theme) do
     for section, color in pairs(sections) do
@@ -109,13 +112,13 @@ local function get_default_component_color(color, options_color, default_color,
     if type(options_color) == 'table' and options_color[kind] then
       return options_color[kind]
     elseif type(options_color) == 'string' then
-      return utils.extract_highlight_colors(options_color, kind)
+      return modules.utils.extract_highlight_colors(options_color, kind)
     end
   end
   if type(default_color) == 'table' then
     return default_color[kind]
   elseif type(default_color) == 'string' then
-    return utils.extract_highlight_colors(default_color, kind)
+    return modules.utils.extract_highlight_colors(default_color, kind)
   end
 end
 
@@ -130,9 +133,9 @@ end
 --   to retrive highlight group
 function M.create_component_highlight_group(color, highlight_tag, options)
   local tag_id = 0
-  while (utils.highlight_exists(table.concat(
+  while (modules.utils.highlight_exists(table.concat(
                              {'lualine', highlight_tag, 'no_mode'}, '_'))
-      or (options.self.section and utils.highlight_exists(table.concat(
+      or (options.self.section and modules.utils.highlight_exists(table.concat(
                              {options.self.section, highlight_tag, 'normal'}, '_')))
 ) do
     highlight_tag = highlight_tag .. '_' .. tostring(tag_id)
@@ -193,12 +196,12 @@ function M.component_format_highlight(highlight_name)
   if highlight_name:find('no_mode') == #highlight_name - #'no_mode' + 1 then
     return '%#' .. highlight_group .. '#'
   end
-  if utils.is_focused() then
+  if modules.utils.is_focused() then
     highlight_group = append_mode(highlight_group)
   else
     highlight_group = highlight_group .. '_inactive'
   end
-  if utils.highlight_exists(highlight_group) then
+  if modules.utils.highlight_exists(highlight_group) then
     return '%#' .. highlight_group .. '#'
   else
     return '%#' .. highlight_name .. '_normal#'
@@ -207,7 +210,7 @@ end
 
 function M.format_highlight(is_focused, highlight_group)
   if highlight_group > 'lualine_c'
-    and not utils.highlight_exists(highlight_group .. '_normal') then
+    and not modules.utils.highlight_exists(highlight_group .. '_normal') then
     highlight_group = 'lualine_' ..
                           section_highlight_map[highlight_group:match(
                               'lualine_(.)')]
@@ -218,7 +221,7 @@ function M.format_highlight(is_focused, highlight_group)
   else
     highlight_name = append_mode(highlight_group)
   end
-  if utils.highlight_exists(highlight_name) then
+  if modules.utils.highlight_exists(highlight_name) then
     return '%#' .. highlight_name .. '#'
   end
   return '%#' .. highlight_group .. '_normal#'
@@ -236,11 +239,11 @@ function M.get_transitional_highlights(left_hl, right_hl)
 
   -- construct the name of hightlight group
   local highlight_name = table.concat({'lualine_transitional',left_hl,'to',right_hl}, '_')
-  if not utils.highlight_exists(highlight_name) then
+  if not modules.utils.highlight_exists(highlight_name) then
     -- Create the highlight_group if needed
     -- Get colors from highlights
-    local fg = utils.extract_highlight_colors(left_hl, 'bg')
+    local fg = modules.utils.extract_highlight_colors(left_hl, 'bg')
-    local bg = utils.extract_highlight_colors(right_hl, 'bg')
+    local bg = modules.utils.extract_highlight_colors(right_hl, 'bg')
     if not fg or not bg then return nil end -- Color retrieval failed
     if bg == fg then return nil end -- Separator won't be visible anyway
     M.highlight(highlight_name, fg, bg, nil)

lua/lualine/init.lua

@@ -1,6 +1,7 @@
 -- Copyright (c) 2020-2021 hoob3rt
 -- MIT license, see LICENSE for more details.
-local modules = require('lualine.utils.lazy_require'){
+local lualine_require = require'lualine_require'
+local modules = lualine_require.lazy_require{
   highlight = 'lualine.highlight',
   loader = 'lualine.utils.loader',
   utils_section = 'lualine.utils.section',
@@ -284,6 +285,7 @@ local function setup(user_config)
   new_config = true
   config = modules.config_module.apply_configuration(user_config)
   vim.go.statusline = "%{%v:lua.require'lualine'.statusline()%}"
+  vim.go.laststatus = 2
 end
 
 return {

lua/lualine/utils/lazy_require.lua

@@ -1,13 +0,0 @@
-return function(modules)
-  return setmetatable({}, {
-    __index = function(self, key)
-      local loaded = rawget(self, key)
-      if loaded ~= nil then return loaded end
-      local module_location = modules[key]
-      if module_location == nil then return nil end
-      local module = require(module_location)
-      rawset(self, key, module)
-      return module
-    end
-  })
-end

lua/lualine/utils/loader.lua

@@ -1,73 +1,20 @@
 -- Copyright (c) 2020-2021 hoob3rt
 -- MIT license, see LICENSE for more details.
+
+local lualine_require = require'lualine_require'
+local require = lualine_require.require
 local notice = require'lualine.utils.notices'
-local utils = require'lualine.utils.utils'
+local is_valid_filename = lualine_require.is_valid_filename
 
-local function lualine_load(patern, use_cache)
+local sep = package.config:sub(1,1)
-  assert(utils.is_valid_filename(patern[#patern]), "Invalid filename")
-  local retval, cache_name = nil, nil
-  local sep = package.config:sub(1,1)
-
-  if use_cache == true then
-    -- Turn {lua, lualine, module, name} -> lualine.module.name
-    -- same formst that require uses
-    -- then check if it's in requires cache
-    local copy_patern = {}
-    local start = patern[1] == 'lua' and 2 or 1
-    local copy_start = 1
-    for i=start, #patern do
-      copy_patern[copy_start] = patern[i]
-      copy_start = copy_start + 1
-    end
-    cache_name = table.concat(copy_patern, '.')
-    if package.loaded[cache_name] then
-      return package.loaded[cache_name]
-    end
-  end
-
-  -- Get all the runtime files that match the patern
-  local files = vim.fn.uniq(vim.api.nvim_get_runtime_file(
-                  table.concat(patern, sep)..'.lua', true))
-  local n_files = #files
-
-  if n_files == 0 then
-    -- No match found
-    error(table.concat(patern, sep) .. " Not found")
-  elseif n_files == 1 then
-    -- when only one is found run that and return it's return value
-    retval =  dofile(files[1])
-  else
-    -- More then 1 found . Use the first one that isn't in lualines repo
-    local lualine_repo_pattern = table.concat({'lualine.nvim', 'lua', 'lualine'}, sep)
-    local file_found = false
-    for _, file in ipairs(files) do
-      if not file:find(lualine_repo_pattern) then
-        retval = dofile(file)
-        file_found = true
-        break
-      end
-    end
-    if not file_found then
-      -- This shouldn't happen but somehow we have multiple files but they
-      -- apear to be in lualines repo . Just run the first one
-      retval =  dofile(files[1])
-    end
-  end
-
-  if use_cache == true and cache_name then
-    package.loaded[cache_name] = retval
-  end
-  return retval
-end
 
 local component_types = {
   luaf = function(component)
     return
-      lualine_load({'lua', 'lualine', 'components', 'special', 'function_component'}, true):new(component)
+      require('lualine.components.special.function_component'):new(component)
   end,
   mod = function(component)
-    local ok, loaded_component = pcall(lualine_load,
+    local ok, loaded_component = pcall(require,'lualine.components.'..component[1])
-                            {'lua', 'lualine', 'components', component[1]}, true)
     if ok then
       component.component_name = component[1]
       loaded_component = loaded_component:new(component)
@@ -78,15 +25,15 @@ local component_types = {
     local stl_expr = component[1] -- Vim's %p %l statusline elements
     component[1] = function() return stl_expr end
     return
-      lualine_load({'lua', 'lualine', 'components', 'special', 'function_component'}, true):new(component)
+      require('lualine.components.special.function_component'):new(component)
   end,
   var = function(component)
     return
-        lualine_load({'lua', 'lualine', 'components', 'special', 'vim_var_component'}, true):new(component)
+        require('lualine.components.special.vim_var_component'):new(component)
   end,
   ['_'] = function(component)
     return
-        lualine_load({'lua', 'lualine', 'components', 'special', 'eval_func_component'}, true):new(component)
+        require('lualine.components.special.eval_func_component'):new(component)
   end
 }
 
@@ -146,7 +93,7 @@ local function load_extensions(config)
   local loaded_extensions = {}
   for _, extension in pairs(config.extensions) do
     if type(extension) == 'string' then
-      local ok, local_extension = pcall(lualine_load, {'lua', 'lualine', 'extensions', extension}, true)
+      local ok, local_extension = pcall(require, 'lualine.extensions.' ..extension)
       if ok then
         local_extension = vim.deepcopy(local_extension)
         load_sections(local_extension.sections, config.options)
@@ -184,7 +131,36 @@ local function load_all(config)
 end
 
 local function load_theme(theme_name)
-  return lualine_load({'lua', 'lualine', 'themes', theme_name}, false)
+  assert(is_valid_filename(theme_name), "Invalid filename")
+  local retval
+  local path = table.concat({'lua', 'lualine', 'themes', theme_name}, sep)..'.lua'
+  local files = vim.fn.globpath(vim.api.nvim_get_option('rtp'),
+                                path, true, true)
+  local n_files = #files
+  if n_files == 0 then
+    -- No match found
+    error(path .. " Not found")
+  elseif n_files == 1 then
+    -- when only one is found run that and return it's return value
+    retval =  dofile(files[1])
+  else
+    -- More then 1 found . Use the first one that isn't in lualines repo
+    local lualine_repo_pattern = table.concat({'lualine.nvim', 'lua', 'lualine'}, sep)
+    local file_found = false
+    for _, file in ipairs(files) do
+      if not file:find(lualine_repo_pattern) then
+        retval = dofile(file)
+        file_found = true
+        break
+      end
+    end
+    if not file_found then
+      -- This shouldn't happen but somehow we have multiple files but they
+      -- apear to be in lualines repo . Just run the first one
+      retval =  dofile(files[1])
+    end
+  end
+  return retval
 end
 
 return {

lua/lualine/utils/utils.lua

@@ -75,11 +75,6 @@ function M.is_focused()
   return tonumber(vim.g.actual_curwin) == vim.fn.win_getid()
 end
 
-function M.is_valid_filename(name)
-  local invalid_chars="[^a-zA-Z0-9_. -]"
-  return name:find(invalid_chars) == nil
-end
-
 function M.charAt(str, pos)
   return string.char(str:byte(pos))
 end

lua/lualine_require.lua

@@ -0,0 +1,47 @@
+local M = {}
+
+M.sep = package.config:sub(1,1)
+
+local source = debug.getinfo(1, "S").source
+if source:sub(1,1) == '@' then
+  local base_start = source:find(table.concat({'lualine.nvim', 'lua', 'lualine_require.lua'}, M.sep))
+  if base_start then
+    source = source:sub(2, base_start + 12 + 1 + 3) -- #lualine.nvim = 12 , #lua = 3.
+    if source then M.plugin_dir = source end
+  end
+end
+
+function M.is_valid_filename(name)
+  local invalid_chars="[^a-zA-Z0-9_. -]"
+  return name:find(invalid_chars) == nil
+end
+
+function M.require(module)
+  if package.loaded[module] then return package.loaded[module] end
+  if M.plugin_dir then
+    local path = M.plugin_dir .. module:gsub('%.', M.sep) .. '.lua'
+    assert(M.is_valid_filename(module), "Invalid filename")
+    if vim.loop.fs_stat(path) then
+      local mod_result = dofile(path)
+      package.loaded[module] = mod_result
+      return mod_result
+    end
+  end
+  return require(module)
+end
+
+function M.lazy_require(modules)
+  return setmetatable({}, {
+    __index = function(self, key)
+      local loaded = rawget(self, key)
+      if loaded ~= nil then return loaded end
+      local module_location = modules[key]
+      if module_location == nil then return nil end
+      local module = M.require(module_location)
+      rawset(self, key, module)
+      return module
+    end
+  })
+end
+
+return M