add weird char detection

home-manager/nvim/config/lua/init.lua

@@ -20,3 +20,4 @@ require("telescope-config")
 require("toggleterm-config")
 require("ts-config")
 require("which-key-config")
+require("weird-chars")

home-manager/nvim/config/lua/weird-chars.lua

@@ -0,0 +1,72 @@
+local ns = vim.api.nvim_create_namespace("weird-chars")
+
+vim.diagnostic.config({
+	virtual_text = true,
+	signs = true,
+	underline = true,
+})
+
+local weird_chars = {
+	["–"] = "en dash found, consider using regular hyphen (-)",
+	["—"] = "em dash found, consider using regular hyphen (-)",
+	["“"] = 'left double quote found, consider using straight quote (")',
+	["”"] = 'right double quote found, consider using straight quote (")',
+	["‘"] = "left single quote found, consider using straight quote (')",
+	["’"] = "right single quote found, consider using straight quote (')",
+	["•"] = "bullet found, consider using regular asterisk (*)",
+	["·"] = "middle dot found",
+	["　"] = "full-width space found, consider using regular space",
+}
+
+local function check_weird_chars()
+	local bufnr = vim.api.nvim_get_current_buf()
+	local lines = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
+	local diagnostics = {}
+
+	for linenr, line in ipairs(lines) do
+		local i = 1
+		while i <= #line do
+			local b = line:byte(i)
+			local char
+
+			-- Check for UTF-8 multi-byte sequences
+			if b >= 0xE2 and b <= 0xEF then
+				-- Likely a 3-byte UTF-8 sequence
+				char = line:sub(i, i + 2)
+				i = i + 3
+			elseif b >= 0xC2 and b <= 0xDF then
+				-- Likely a 2-byte UTF-8 sequence
+				char = line:sub(i, i + 1)
+				i = i + 2
+			else
+				-- Single byte character
+				char = line:sub(i, i)
+				i = i + 1
+			end
+
+			if weird_chars[char] then
+				table.insert(diagnostics, {
+					bufnr = bufnr,
+					lnum = linenr - 1,
+					col = i - #char - 1,
+					message = weird_chars[char],
+					severity = vim.diagnostic.severity.WARN,
+				})
+			end
+		end
+	end
+
+	vim.diagnostic.set(ns, bufnr, diagnostics)
+end
+
+-- Create autocommand group
+local group = vim.api.nvim_create_augroup("WeirdChars", { clear = true })
+
+-- Set up autocommands
+vim.api.nvim_create_autocmd({ "BufEnter", "BufWritePost", "TextChanged", "InsertLeave" }, {
+	group = group,
+	callback = check_weird_chars,
+})
+
+-- Create commands for manual checking
+vim.api.nvim_create_user_command("CheckWeirdChars", check_weird_chars, {})