How to modify only the background colour of a colourscheme in neovim using lua

Question

I am slowly switching my neovim configurations to Lua. I am currently using the colour scheme https://github.com/nightsense/snow. It sets the background colour to a light-grey, while I want it to be a darker tone of grey. Previously, when using vimL, I used to use the following snippet to change the background colour (to match my terminal colour).

set termguicolors
try
    colorscheme snow
    set background=dark
    hi Normal ctermbg=232 guibg=#0a0a0a
catch /^Vim\%((\a\+)\)\=:E185/
    colorscheme default
endtry

I am trying to achieve the same in my Neovim Lua based configuration. I tried the following piece of code to do so.

vim.cmd('set background=dark')
vim.cmd('colorscheme snow')
vim.cmd('hi Normal guibg=#0a0a0a')

Unfortunately, this does not seem to work. What am I doing wrong here?

Answer 1

This was how I sorted out my problem in the end

vim.api.nvim_command([[
    augroup ChangeBackgroudColour
        autocmd colorscheme * :hi normal guibg=#0a0a0a
    augroup END
]])
vim.o.termguicolors = true
vim.cmd [[silent! colorscheme snow]]

Answer 2

I see no particular problem about Lua syntax. Perhaps, you simply forgot to set termguicolors or your console does not support 24-bit color at all. Anyway, the following seems to work just fine:

    vim.o.termguicolors = true
    vim.o.background = "dark"
    vim.cmd [[
        silent! colorscheme snow
        hi Normal guibg=#0a0a0a
    ]]

But note that you have to "patch" background after any colorscheme change, so usually one does make use of an auto-command.