File

util/format.lua @ 10399:270cb2821566

mod_ping: Remove ad-hoc command 17:27:40 <Ge0rG> Zash: the Ping thing is absolutely worthless 17:27:55 <Zash> The command provided by mod_ping? 17:27:59 <pep.> To own server? 17:28:14 <Ge0rG> the Ping command in mod_admin_web, whatever it maps to 17:28:29 <Ge0rG> > Pong > 2019-11-07T16:28:16Z What am I supposed to do with that result? 17:28:29 <Zash> Yeah, mod_ping provides that 17:28:41 <Ge0rG> Is it a ping to my own server? Where's the RTT? 17:28:48 <Zash> Dunno if it's useful for more than verifying that the adhoc command system works 17:29:02 <Ge0rG> (it lags, but there is no indication of how much) 17:29:14 <Zash> It can't really test that itself 17:29:52 <Zash> Anyone opposed to deleting it? 17:30:42 <Zash> Half the module 17:42:47 <MattJ> Zash, I'm fine with removing it
author Kim Alvefur <zash@zash.se>
date Thu, 07 Nov 2019 19:23:42 +0100
parent 10035:386f085820e6
child 11638:5f4a657136bc
line wrap: on
line source

--
-- A string.format wrapper that gracefully handles invalid arguments
--

local tostring = tostring;
local unpack = table.unpack or unpack; -- luacheck: ignore 113/unpack
local pack = require "util.table".pack; -- TODO table.pack in 5.2+
local type = type;
local dump = require "util.serialization".new("debug");
local num_type = math.type or function (n)
	return n % 1 == 0 and n <= 9007199254740992 and n >= -9007199254740992 and "integer" or "float";
end

-- In Lua 5.3+ these formats throw an error if given a float
local expects_integer = { c = true, d = true, i = true, o = true, u = true, X = true, x = true, };

local function format(formatstring, ...)
	local args = pack(...);
	local args_length = args.n;

	-- format specifier spec:
	-- 1. Start: '%%'
	-- 2. Flags: '[%-%+ #0]'
	-- 3. Width: '%d?%d?'
	-- 4. Precision: '%.?%d?%d?'
	-- 5. Option: '[cdiouxXaAeEfgGqs%%]'
	--
	-- The options c, d, E, e, f, g, G, i, o, u, X, and x all expect a number as argument, whereas q and s expect a string.
	-- This function does not accept string values containing embedded zeros, except as arguments to the q option.
	-- a and A are only in Lua 5.2+


	-- process each format specifier
	local i = 0;
	formatstring = formatstring:gsub("%%[^cdiouxXaAeEfgGqs%%]*[cdiouxXaAeEfgGqs%%]", function(spec)
		if spec ~= "%%" then
			i = i + 1;
			local arg = args[i];

			local option = spec:sub(-1);
			if arg == nil then
				args[i] = "nil";
				spec = "<%s>";
			elseif option == "q" then
				args[i] = dump(arg);
				spec = "%s";
			elseif option == "s" then
				args[i] = tostring(arg);
			elseif type(arg) ~= "number" then -- arg isn't number as expected?
				args[i] = tostring(arg);
				spec = "[%s]";
			elseif expects_integer[option] and num_type(arg) ~= "integer" then
				args[i] = tostring(arg);
				spec = "[%s]";
			end
		end
		return spec;
	end);

	-- process extra args
	while i < args_length do
		i = i + 1;
		local arg = args[i];
		if arg == nil then
			args[i] = "<nil>";
		else
			args[i] = tostring(arg);
		end
		formatstring = formatstring .. " [%s]"
	end

	return formatstring:format(unpack(args));
end

return {
	format = format;
};