misc(nvim): embolden statusline diff/diagnostics, tidy lualine setup

Stamp bold onto lualine's generated lualine_b_diff*/diagnostics*
highlight groups with nvim_set_hl update=true so only the bold bit
changes (fg and section b background preserved), re-applied after
each lualine (re)build: initial setup, theme switch, ColorScheme.

Also carry the component/section separators into the background
OptionSet handler so they survive the light/dark theme swap.

1 files changed, 25 insertions, 0 deletions

diff --git a/plugin/50-statusline.lua b/plugin/50-statusline.lua
index e32800e..10c88f6 100644
--- a/plugin/50-statusline.lua
+++ b/plugin/50-statusline.lua
@@ -23,6 +23,27 @@ local function statuses()
 	return (vim.b.autoformat and "+F" or "") .. (vim.o.spell and spell_status() or "")
 end
 
+-- lualine builds its own section-b-backed highlights for the diff/diagnostics
+-- components (lualine_b_diff_added_normal, lualine_b_diagnostics_error_normal,
+-- ...). Stamp bold onto them with update=true so only the bold attribute
+-- changes -- fg and section b's background are left untouched. Must run after
+-- lualine (re)creates the groups: initial setup, theme switch, colorscheme.
+local function bold_diff_diag()
+	for name in pairs(vim.api.nvim_get_hl(0, {})) do
+		if name:find("^lualine_b_diff") or name:find("^lualine_b_diagnostics") then
+			vim.api.nvim_set_hl(0, name, { bold = true, update = true })
+		end
+	end
+end
+
+vim.api.nvim_create_autocmd("ColorScheme", {
+	desc = "Re-bold lualine diff/diagnostics after colorscheme rebuild",
+	group = vim.g.dotfiles.augroup,
+	callback = function()
+		vim.schedule(bold_diff_diag)
+	end,
+})
+
 local lualine_sections = {
 	lualine_c = { statuses, "filename" },
 	lualine_x = { "encoding", "fileformat", "filetype", "lsp_status" },
@@ -38,8 +59,11 @@ vim.api.nvim_create_autocmd("OptionSet", {
 			options = {
 				theme = vim.o.background == "light" and "solarized_light" or "solarized_dark",
 				disabled_filetypes = { "netrw", "qf" },
+				component_separators = { left = "|", right = "|" },
+				section_separators = { left = "", right = "" },
 			},
 		})
+		vim.schedule(bold_diff_diag)
 	end,
 })
 
@@ -47,6 +71,7 @@ lualine.setup({
 	options = { theme = vim.o.background == "light" and "solarized_light" or "solarized_dark" },
 	sections = lualine_sections,
 })
+vim.schedule(bold_diff_diag)
 
 vim.api.nvim_create_user_command("LualineConfig", function()
 	vim.notify(vim.inspect(lualine.get_config()))