Feat: Add icon to `filename` component

[tapyu]

Requested feature

An option to filename component that allows displaying the filetype icon along with the name. With the current components, the best that I could achieve was the following:

It is a reasonable result, but the file name and the type icon are kind of distant... Furthermore, I had to disable the file status option, otherwise it would be in the middle...

Motivation

In my humble opinion, filename and filetype carry very close meanings and could be displayed together, as I tried to do with the available components.

setup

local is_status_ok, lualine = pcall(require, "lualine")
if not is_status_ok then
  return
end

lualine.setup {
  options = {
    icons_enabled = true,
    theme = 'codedark',
    component_separators = { left = '', right = ''},
    section_separators = { left = '', right = ''},
    disabled_filetypes = {},
    always_divide_middle = true,
    globalstatus = false,
  },
  sections = {
    lualine_a = {'mode'},
    lualine_b = {'branch', 'diff', 'diagnostics'},
    lualine_c = {{'filename', file_status = false, separator = ''}, {'filetype', icon_only = true}},
    lualine_x = {'encoding', 'fileformat'},
    lualine_y = {'progress'},
    lualine_z = {'location'}
  },
  inactive_sections = {
    lualine_a = {},
    lualine_b = {},
    lualine_c = {'filename'},
    lualine_x = {'location'},
    lualine_y = {},
    lualine_z = {}
  },
  tabline = {},
  extensions = {}
}

[shadmansaleh]

You can put the fitletype icon in front of filename and also can control the spacing with padding option. You're quite close actually .

-    lualine_c = {{'filename', file_status = false, separator = ''}, {'filetype', icon_only = true}},
+    lualine_c = {{'filetype', icon_only = true, separator = '', padding={right=0, left=1}}, 'filename' },

[tapyu]

I thought just setting the padding to zero wouldn't be enough. Now it looks fine. Thanks.