lsp: configure lua to ignore unused locals starting with '_'

init.lua

@@ -201,7 +201,7 @@ local lsp = require("lspconfig")
 
 -- Use an on_attach function to only map the following keys
 -- after the language server attaches to the current buffer
-local on_lsp_attach = function(client, bufnr)
+local on_lsp_attach = function(_client, _bufnr)
 	vim.keymap.set("n", "gD", vim.lsp.buf.declaration)
 	vim.keymap.set("n", "gd", vim.lsp.buf.definition)
 	vim.keymap.set("n", "K", vim.lsp.buf.hover)
@@ -232,7 +232,10 @@ local servers = {
 		settings = {
 			Lua = {
 				runtime = { version = "LuaJIT" },
-				diagnostics = { globals = { "vim" } },
+				diagnostics = {
+					globals = { "vim" },
+					unusedLocalExclude = { "_*" },
+				},
 				workspace = {
 					library = vim.api.nvim_get_runtime_file("", true),
 				},
@@ -338,7 +341,6 @@ for ft, ft_linters in pairs(linters) do
 						lint.try_lint(nil, { ignore_errors = true })
 					end,
 				})
-				lint.try_lint(nil, { ignore_errors = true })
 			end,
 		})
 	end
@@ -425,7 +427,7 @@ end
 g.gitblame_enabled = 0
 ---- gitsigns.nvim
 require("gitsigns").setup({
-	on_attach = function(bufnr)
+	on_attach = function(_bufnr)
 		local gs = package.loaded.gitsigns
 
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