How to set a unique highlight group for a specific picker?

[KaihoCD]

I’d like to set a unique highlight group for the input window in snacks.explorer without affecting other pickers. I’ve tried several approaches but haven’t found a reliable solution yet.

The configuration below works occasionally when Neovim starts, but most of the time it doesn’t — maybe due to race conditions during initialization? I’m not entirely sure.

picker = {
	sources = {
		explorer = {
			win = {
				input = {
					wo = {
						-- I also tried using winhighlight, but that didn’t work at all.
						winhl = table.concat({
							'Normal:Normal',
							'NormalNC:Normal',
							'FloatBorder:Normal',
						}, ','),
					},
				},
			},
		},
	},
}

While I know it’s possible to modify the highlight group dynamically by fetching the window ID, I’d prefer a solution through the plugin’s configuration to avoid a visible flicker effect when the highlight changes after the window is created.

Here’s the kind of result I’m hoping to achieve:

I’ve been struggling with this for a while and would really appreciate any help. Thanks in advance! 😭

[drowning-cat]

You can’t do that using win.input.wo.winhighlight, because snacks.nvim overrides this field with its default configuration.

In particular, Snacks.win.resolve is equivalent to vim.tbl_deep_extend('force'), which gives preference to the rightmost table:

snacks.nvim/lua/snacks/picker/core/input.lua

Lines 19 to 49 in bc0630e

	self.win = Snacks.win(Snacks.win.resolve(picker.opts.win.input, {
	show = false,
	enter = false,
	height = 1,
	ft = "regex",
	on_buf = function(win)
	-- HACK: this is needed to prevent Neovim from stopping insert mode,
	-- for any other picker input we are leaving.
	local buf = vim.api.nvim_get_current_buf()
	if buf ~= win.buf and vim.bo[buf].filetype == "snacks_picker_input" then
	vim.bo[buf].buftype = "nofile"
	end
	vim.fn.prompt_setprompt(win.buf, "")
	vim.bo[win.buf].modified = false
	local text = picker.opts.live and self.filter.search or self.filter.pattern
	vim.api.nvim_buf_set_lines(win.buf, 0, -1, false, { text })
	vim.bo[win.buf].modified = false
	end,
	on_win = function()
	self:highlights()
	end,
	bo = {
	filetype = "snacks_picker_input",
	buftype = "prompt",
	},
	wo = {
	statuscolumn = self:statuscolumn(),
	cursorline = false,
	winhighlight = Snacks.picker.highlight.winhl("SnacksPickerInput"),
	},
	}))

[KaihoCD]

Alright, but why does the "winhl" field occasionally succeed? I saw a glimmer of hope in the "winhl" field.
Also, if you have any good ideas to meet my needs, I beg of you, please do tell me. Thank you so much!
Anyway, thanks for your reply.

[drowning-cat]

Actually, you can use this:

opts = {
  picker = {
    sources = {
      explorer = {
        -- https://github.com/folke/snacks.nvim/blob/bc0630e43be5699bb94dadc302c0d21615421d93/lua/snacks/picker/config/layouts.lua#L22-L42
        layout = {
          preview = 'main',
          layout = {
            backdrop = false,
            width = 40,
            min_width = 40,
            height = 0,
            position = 'left',
            border = 'none',
            box = 'vertical',
            {
              win = 'input',
              height = 1,
              wo = {
                -- Snacks.picker.highlight.winhl('SnacksPickerInput')
                -- Use full string:
                --  FloatBorder:SnacksPickerInputBorder,FloatFooter:SnacksPickerInputFooter,FloatTitle:SnacksPickerInputTitle,NormalFloat:SnacksPickerInput,CursorLine:SnacksPickerInputCursorLine
                winhighlight = 'FloatBorder:Special',
              },
              border = 'rounded',
              title = '{title} {live} {flags}',
              title_pos = 'center',
            },
            { win = 'list', border = 'none' },
            { win = 'preview', title = '{preview}', height = 0.4, border = 'top' },
          },
        },

[KaihoCD]

Thank you for your help! This perfectly solved my needs. 😊