From c030a380ef697dad7ff099f3343830c2d64a1ccd Mon Sep 17 00:00:00 2001
From: shadmansaleh <13149513+shadmansaleh@users.noreply.github.com>
Date: Thu, 25 Nov 2021 12:57:00 +0600
Subject: [PATCH] feat: add support for inline custom components

---
 lua/lualine/component.lua    |  2 ++
 lua/lualine/config.lua       | 12 ++++++-----
 lua/lualine/utils/loader.lua | 12 ++++++++---
 lua/lualine/utils/utils.lua  | 42 ++++++++++++++++++++++++++++++++++++
 4 files changed, 60 insertions(+), 8 deletions(-)

diff --git a/lua/lualine/component.lua b/lua/lualine/component.lua
index 853ec9a..a9c25fb 100644
--- a/lua/lualine/component.lua
+++ b/lua/lualine/component.lua
@@ -18,6 +18,8 @@ function M:__tostring()
   return str
 end
 
+M.__is_lualine_component = true
+
 ---initialize new component
 ---@param options table options for component
 function M:init(options)
diff --git a/lua/lualine/config.lua b/lua/lualine/config.lua
index fc794e2..10ead32 100644
--- a/lua/lualine/config.lua
+++ b/lua/lualine/config.lua
@@ -1,5 +1,7 @@
 -- Copyright (c) 2020-2021 hoob3rt
 -- MIT license, see LICENSE for more details.
+local utils = require 'lualine.utils.utils'
+
 local config = {
   options = {
     icons_enabled = true,
@@ -46,7 +48,7 @@ end
 ---@return table copy of config
 local function apply_configuration(config_table)
   if not config_table then
-    return vim.deepcopy(config)
+    return utils.deepcopy(config)
   end
   local function parse_sections(section_group_name)
     if config_table[section_group_name] == nil then
@@ -57,7 +59,7 @@ local function apply_configuration(config_table)
       return
     end
     for section_name, section in pairs(config_table[section_group_name]) do
-      config[section_group_name][section_name] = vim.deepcopy(section)
+      config[section_group_name][section_name] = utils.deepcopy(section)
     end
   end
   parse_sections 'options'
@@ -65,17 +67,17 @@ local function apply_configuration(config_table)
   parse_sections 'inactive_sections'
   parse_sections 'tabline'
   if config_table.extensions then
-    config.extensions = vim.deepcopy(config_table.extensions)
+    config.extensions = utils.deepcopy(config_table.extensions)
   end
   config.options.section_separators = fix_separators(config.options.section_separators)
   config.options.component_separators = fix_separators(config.options.component_separators)
-  return vim.deepcopy(config)
+  return utils.deepcopy(config)
 end
 
 --- returns current active config
 ---@return table a copy of config
 local function get_current_config()
-  return vim.deepcopy(config)
+  return utils.deepcopy(config)
 end
 
 return {
diff --git a/lua/lualine/utils/loader.lua b/lua/lualine/utils/loader.lua
index 5b37bbf..258982a 100644
--- a/lua/lualine/utils/loader.lua
+++ b/lua/lualine/utils/loader.lua
@@ -4,6 +4,7 @@
 local lualine_require = require 'lualine_require'
 local require = lualine_require.require
 local modules = lualine_require.lazy_require {
+  utils = 'lualine.utils.utils',
   notice = 'lualine.utils.notices',
 }
 local is_valid_filename = lualine_require.is_valid_filename
@@ -11,6 +12,10 @@ local sep = lualine_require.sep
 
 --- function that loads specific type of component
 local component_types = {
+  -- loads custion component
+  custom = function(component)
+    return component[1](component)
+  end,
   --- loads lua functions as component
   lua_fun = function(component)
     return require 'lualine.components.special.function_component'(component)
@@ -53,8 +58,7 @@ local component_types = {
 local function component_loader(component)
   if type(component[1]) == 'function' then
     return component_types.lua_fun(component)
-  end
-  if type(component[1]) == 'string' then
+  elseif type(component[1]) == 'string' then
     -- load the component
     if component.type ~= nil then
       if component_types[component.type] and component.type ~= 'lua_fun' then
@@ -81,6 +85,8 @@ component type '%s' isn't recognised. Check if spelling is correct.]],
     else
       return component_types['_'](component)
     end
+  elseif type(component[1]) == 'table' then
+    return component_types.custom(component)
   end
 end
 
@@ -168,7 +174,7 @@ end
 local function load_sections(sections, options)
   for section_name, section in pairs(sections) do
     for index, component in pairs(section) do
-      if type(component) == 'string' or type(component) == 'function' then
+      if (type(component) == 'string' or type(component) == 'function') or modules.utils.is_component(component) then
         component = { component }
       end
       if is_valid_component_type(index, component) then
diff --git a/lua/lualine/utils/utils.lua b/lua/lualine/utils/utils.lua
index b089601..d2a7eca 100644
--- a/lua/lualine/utils/utils.lua
+++ b/lua/lualine/utils/utils.lua
@@ -101,4 +101,46 @@ function M.charAt(str, pos)
   return string.char(str:byte(pos))
 end
 
+-- deepcopy adapted from penlight
+-- https://github.com/lunarmodules/Penlight/blob/0653cdb05591454a9804a7fee8c873b8f06b0b8f/lua/pl/tablex.lua#L98-L122
+local function cycle_aware_copy(t, cache)
+  if type(t) ~= 'table' then
+    return t
+  end
+  if cache[t] then
+    return cache[t]
+  end
+  local res = {}
+  cache[t] = res
+  local mt = getmetatable(t)
+  for k, v in pairs(t) do
+    k = cycle_aware_copy(k, cache)
+    v = cycle_aware_copy(v, cache)
+    res[k] = v
+  end
+  setmetatable(res, mt)
+  return res
+end
+
+--- make a deep copy of a table, recursively copying all the keys and fields.
+-- This supports cycles in tables; cycles will be reproduced in the copy.
+-- This will also set the copied table's metatable to that of the original.
+-- @within Copying
+-- @tab t A table
+-- @return new table
+function M.deepcopy(t)
+  return cycle_aware_copy(t, {})
+end
+
+--- Check if comp is a lualine component
+--- @param comp any
+--- @return boolean
+function M.is_component(comp)
+  if type(comp) ~= 'table' then
+    return false
+  end
+  local mt = getmetatable(comp)
+  return mt and mt.__is_lualine_component == true
+end
+
 return M