Feature Suggestion: also set listchars depending on tabs/spaces

[chrisgrieser]

I find it useful to only show tab via listchars when using spaces and vice versa, since that allows me to quickly identify the use of the wrong type of indention in a file.

Currently, I run a simple autocommand like this to adjust listchars depending whether the buffer uses tabs or spaces:

autocmd("BufReadPost", {
	callback = function()
		-- defered, to ensure it runs after `:GuessIndent`
		vim.defer_fn(function()
			opt_local.listchars = vim.opt_global.listchars:get() -- copy the global
			if bo.expandtab then
				opt_local.listchars:append { tab = "? " }
				opt_local.listchars:append { lead = " " }
			else
				opt_local.listchars:append { tab = "  " }
				opt_local.listchars:append { lead = "�" }
			end
		end, 5)
	end,
})

I was thinking that adjusting listchars would actually make a lot of sense for in the context of this plugin (and would also save one from using hacky solutions like deferring that autocmd)