Cannot require modules with init.lua

[masakk1]

The finding
Originally I was going to make a post about how I couldn't get modules that have a init.lua to work, even though it worked for lua 5.4.
But miraculously, I decided to check the `package.path` and compared love's luajit to lua 5.4's

It just so happed that Löve (or luajit) is missing a certain package path: `./?/init.lua`

Then I also figured out that this issue does not happen if the `main.lua` file is at the root of the project. But I'm making a multiplayer game so I added client/ and server/ folder folders which to run love on.

The issue
If the `main.lua` file isn't at the root of the project folder, (i.e. `love client/` instead of `love .`) then any requires to a module using the module/init.lua scheme will not work and throw an error.

This doesn't happen on lua 5.4.

The workaround
We know that we are missing `./?/init.lua`, so we can just append it to the `package.path` variable:

Code: Select all

-- also include a semi-colon!
package.path = package.path .. ";./?/init.lua"

Wrapping up
Why? I do not have the will to go digging for commits and check when this feature was added or removed to lua 5.4 or luaJIT (I checked and yes, it's not Löve's fault but luaJIT's).

I hope that this is helpful to someone in the future. Please suggest any changes or edits to this solution. Even the name of the post so more people can find it.

Oh and, someone let me know if they know why this happens.

Note: I use Linux btw, particularly fedora, but also happens on Ubuntu - I don't know if that's related

The actual solution
Don't put two `main.lua`s. Always one on the root of the project. Then parse arguments such as `--server` and run a server script from there.

Parse arguments on: love.load

love doesn't use package.path as its primary module searcher, it uses a module searcher from love.filesystem instead which does look for init.lua.

I recommend structuring your project so that main.lua is at the root, and then you pick whether to load client or server files from there based on a command-line parameter parsed from that main.lua (or something similar). It'll save you a lot of confusion and inconsistencies down the road.

[slime]

love doesn't use package.path as its primary module searcher, it uses a module searcher from love.filesystem instead which does look for init.lua.

I recommend structuring your project so that main.lua is at the root, and then you pick whether to load client or server files from there based on a command-line parameter parsed from that main.lua (or something similar). It'll save you a lot of confusion and inconsistencies down the road.

[masakk1]

I recommend structuring your project so that main.lua is at the root, and then you pick whether to load client or server files from there based on a command-line parameter parsed from that main.lua (or something similar).

I see. I investigated how to do so, it means changing some of my code structure, but seems very doable. I'll give it a shot!

Also, can you please allow the post if I tweak it to make that the solution? There isn't any information online about this exact problem unfortunately... so please consider

Edit: I'd also change the title
Edit2: I'm dumb I thought it wasn't approved. My bad!

[masakk1]

I recommend structuring your project so that main.lua is at the root

There's only one slight problem. I use a different configuration for the server to disable the display and not show a window. How can I split `conf.lua` in that case?

Specially because `love.conf` runs before `love.load` does...

[MrFariator]

You can delay window creation by setting the window module to false in conf.lua, and then calling love.window.setMode later (if you want to create a window). At the end of love.load, for example. So, you could just have a separate configuration file, maybe with a boolean field that is checked to use if a window should exist, and you change this field accordingly if setting up a server or client.

[masakk1]

You can delay window creation by setting the window module to false in conf.lua, and then calling love.window.setMode later (if you want to create a window). At the end of love.load, for example. So, you could just have a separate configuration file, maybe with a boolean field that is checked to use if a window should exist, and you change this field accordingly if setting up a server or client.

I can't seem to get that to work...

This is what I tried but no window appears:

Code: Select all

function love.load(args)
	parse_args(args)

	if not _G.isServer then
		love.window.setMode(800, 600)
		require("client")
	else
		require("server")
	end
end

Edit: the configuration file is as follows:

Code: Select all

function love.conf(t)
	t.window = false
end

[MrFariator]

What does your parse_args function do?

[masakk1]

What does your parse_args function do?

It just reads the args and whether or not there is a `--server` flag, then set the variable isServer to true.

Code: Select all

local function parse_args(args)
	for i, arg in pairs(args) do
		if arg == "--server" or arg == "-s" then
			_G.isServer = true
		elseif arg == "--debug" or arg == "-d" then
			_G.DEBUG = true
			_G._ANTICHEAT_DEBUG = true
		end
	end
end

function love.load(args)
	parse_args(args)

	if not _G.isServer then
		require("client")
	else
		require("server")
	end
end

The client and server requires are really the previous main.lua's i had.

[MrFariator]

Works fine on my end. First I ran it with -s, no window was created, and then second run I passed no cli arguments and a window was created.
conf.lua is the same you listed.

lovec output.png (41.69 KiB) Viewed 2323 times

[masakk1]

Well uhh... I don't really know what I did wrong before, but yeah, it works.

Thanks!