Fix not being buffer scoped. Previously if any LSP attached to any buffer

had SignatureHelp capability then SigHelp would trigger in even buffers with
an LSP attached that didn't support SignatureHelp, which would cause an error.

lua/sighelp/helper.lua

@@ -109,12 +109,11 @@ local function make_signature_lines(signature_help, maxlen)
 	vim.list_extend(lines, vim.split(signature.label, "\n", { plain = true, trimempty = true }))
 
 	local wrapped_lines = {}
-	for _, ll in ipairs(lines) do
+	for _, l in ipairs(lines) do
-		vim.list_extend(wrapped_lines, _wrap_lines(ll, maxlen))
+		vim.list_extend(wrapped_lines, _wrap_lines(l, maxlen))
 	end
 	return wrapped_lines
 end
-
 local function make_doc_lines(result, ft)
 	local active_signature = result.activeSignature or 0
 	local signature = result.signatures[active_signature + 1]
@@ -319,17 +318,24 @@ local function create_float_windows(result, syntax, opts)
 	syntax = syntax or "text"
 	vim.bo[sig_bufnr].syntax = syntax
 	vim.bo[sig_bufnr].ft = syntax
+	vim.bo[sig_bufnr].bufhidden = "hide"
 	vim.treesitter.start(sig_bufnr)
+
 	vim.bo[doc_bufnr].syntax = "markdown"
 	vim.bo[doc_bufnr].ft = "markdown"
+	vim.bo[doc_bufnr].bufhidden = "hide"
 	vim.treesitter.start(doc_bufnr)
 
 	local sig_content = make_signature_lines(result, opts.max_width)
 	local doc_content = make_doc_lines(result, syntax)
+
 	---@diagnostic disable-next-line: param-type-mismatch
 	api.nvim_buf_set_lines(sig_bufnr, 0, -1, true, sig_content)
+	vim.bo[sig_bufnr].modifiable = false
+
 	---@diagnostic disable-next-line: param-type-mismatch
 	api.nvim_buf_set_lines(doc_bufnr, 0, -1, true, doc_content)
+	vim.bo[doc_bufnr].modifiable = false
 
 	local sig_float_options, doc_float_options = _make_floating_popup_options(sig_content, doc_content, opts)
 	return function()
@@ -337,8 +343,6 @@ local function create_float_windows(result, syntax, opts)
 		vim.wo[sig_winnr].conceallevel = 2
 		vim.wo[sig_winnr].foldenable = false
 		vim.wo[sig_winnr].winblend = opts.winblend
-		vim.bo[sig_bufnr].modifiable = false
-		vim.bo[sig_bufnr].bufhidden = "hide"
 		-- save focus_id
 		api.nvim_buf_set_var(bufnr, "lsp_sig_win", sig_winnr)
 		return sig_bufnr, sig_winnr, sig_content
@@ -347,8 +351,6 @@ local function create_float_windows(result, syntax, opts)
 		vim.wo[doc_winnr].conceallevel = 2
 		vim.wo[doc_winnr].foldenable = false
 		vim.wo[doc_winnr].winblend = opts.winblend
-		vim.bo[doc_bufnr].modifiable = false
-		vim.bo[doc_bufnr].bufhidden = "hide"
 
 		-- save focus_id
 		api.nvim_buf_set_var(doc_bufnr, "lsp_doc_win", doc_winnr)

lua/sighelp/init.lua

@@ -19,7 +19,6 @@ function SignatureHelp.new()
 		markid = nil,
 		timer = nil,
 		current_signatures = nil,
-		enabled = false,
 		current_signature_idx = nil,
 
 		doc_winnr = nil,
@@ -179,12 +178,18 @@ function SignatureHelp:display_doc_win()
 	if self.doc_win_showing then
 		return
 	else
+		self.active_winnr = vim.api.nvim_get_current_win()
 		self.doc_bufnr, self.doc_winnr = self._display_doc_win()
 		self.doc_win_showing = true
 		self.doc_win_focused = true
 		vim.api.nvim_set_current_win(self.doc_winnr)
 
-		exit_docs = function()
+		-- set window variable that can be checked externally for i.e. setting keymaps
+		local w = vim.w
+		w.sighelp_doc_win = true
+		vim.w = w
+
+		local exit_docs = function()
 			vim.api.nvim_set_current_win(self.active_winnr)
 			vim.fn.feedkeys("i", "t") --put us back into insert mode
 			self.doc_win_focused = false
@@ -208,7 +213,7 @@ function SignatureHelp:display_doc_win()
 end
 
 function SignatureHelp:trigger()
-	if not self.enabled then
+	if not vim.b.signatureHelp then
 		return
 	end
 
@@ -239,18 +244,27 @@ function SignatureHelp:trigger()
 end
 
 function SignatureHelp:check_capability()
-	local clients = vim.lsp.get_clients()
+	local bufnr = vim.api.nvim_get_current_buf()
+	local clients = vim.lsp.get_clients({ bufnr = bufnr })
 	for _, client in ipairs(clients) do
 		if client.server_capabilities.signatureHelpProvider then
-			self.enabled = true
+			vim.b.signatureHelp = true
 			return
 		end
 	end
-	self.enabled = false
 end
 
 function SignatureHelp:setup_autocmds()
+	api.nvim_create_autocmd({ "LspAttach", "BufEnter" }, {
+		-- group = group,
+		callback = function()
+			vim.defer_fn(function()
 				local group = api.nvim_create_augroup("LspSignatureHelp", { clear = true })
+				self:check_capability()
+
+				if not vim.b.signatureHelp then
+					return
+				end
 
 				local function debounced_trigger()
 					if self.timer then
@@ -274,7 +288,10 @@ function SignatureHelp:setup_autocmds()
 					group = group,
 					callback = function()
 						vim.defer_fn(function()
-				if self.active_winnr == vim.api.nvim_get_current_win() and vim.api.nvim_get_mode().mode == "n" then
+							if
+								self.active_winnr == vim.api.nvim_get_current_win()
+								and vim.api.nvim_get_mode().mode == "n"
+							then
 								self:hide_sig_win()
 								self:hide_doc_win()
 							end
@@ -301,12 +318,6 @@ function SignatureHelp:setup_autocmds()
 						end
 					end,
 				})
-
-	api.nvim_create_autocmd("LspAttach", {
-		group = group,
-		callback = function()
-			vim.defer_fn(function()
-				self:check_capability()
 			end, 100)
 		end,
 	})
@@ -389,7 +400,6 @@ function M.setup(opts)
 		group = vim.api.nvim_create_augroup("LspSignatureColors", { clear = true }),
 		callback = setup_highlights,
 	})
-
 	-- Setup autocmds
 	signature_help:setup_autocmds()