Relative file paths

[Straskal]

Hi there!

I'm having issues regarding relative file paths for assets (images) and require paths (other lua files).

• It appears that when running my program through the debugger, all paths are relative to the lldebugger.lua instead of the lua53.exe.

I have my launch.json configured to use the lua53.exe interpreter and main.lua as my entry file.

Folder structure:

• lua53.exe
• main.lua
• imageLoader.lua
• assets
  • image.png

main.lua is not able to find imageLoader.lua via require()

I bundled the two files together to avoid require(), but then my program is unable to find the image.

Any help or work arounds would be greatly appreciated!

Thank you.

[astrochili]

I have the same problem on macOS, can't require local lua modules.

I'm looking forward to the solution, because this is the only debugger that really works 🥳. Nothing else works on my mac 😟.

[astrochili]

Found a dirty and hacky solution. I created the separated debug.lua file that I run with debugger:

debug.vscode = os.getenv("LOCAL_LUA_DEBUGGER_VSCODE") == "1"

if debug.vscode then
    local separator = string.sub(package.config, 1, 1)
    local filePath = debug.getinfo(1).short_src
    local rootFolder = string.gsub(filePath, "^(.+"..separator..")[^"..separator.."]+$", "%1");
    package.path = rootFolder .. [[?.lua]]
end

dofile("main.lua")

[Straskal]

That work around works perfectly for now. @astrochili Thanks!

[tomblind]

Have you tried setting cwd in your launch.json?

    "configurations": [
        {
            "name": "Debug",
            "type": "lua-local",
            "request": "launch",
            "program": {
                "lua": "lua53.exe",
                "file": "main.lua"
            },
            "cwd": "${workspaceFolder}"
        }
    ]

[astrochili]

Have you tried setting cwd in your launch.json?

It doesn't help me, a similar error.

[astrochili]

Another problem is the luarocks libraries finding.

For example, luarocks installed the lume module to /usr/local/var/homebrew/linked/luarocks/share/lua/5.3/lume.lua. And the code require("lume") works perfectly with Lua in the terminal.

But the debugger tries to find modules in this short list of paths:

no field package.preload['lume']
no file '/Users/.../.vscode/extensions/tomblind.local-lua-debugger-vscode-0.1.3/debugger/lume.lua'
no file '/usr/local/lib/lua/5.3/lume.so'
no file '/usr/local/lib/lua/5.3/loadall.so'
no file './lume.so'

It looks like the debugger doesn't check the paths list that defined in the system for succesful modules finding.

[tomblind]

You're on OSX, right? It seems environment variables like LUA_PATH aren't passed to the child process in OSX (see # 5 #7). I don't have a Mac right now so I'll need to find one to debug this issue.

[tomblind]

Thinking about it, this issue must be different since the debugger script itself is being found.

[astrochili]

You're on OSX, right?

Yes. Feel free to ask any questions or test tasks, maybe I can help you.

[astrochili]

Wow. Found a more clean solution in #10 that solves all my path finding problems. Just add this to debug configutation:

"env": {
  "LUA_PATH": "./?.lua;[ADDITIONAL_PATHS]"
}

where [ADDITIONAL_PATHS] in my case is all that luarocks path terminal command returns. The final configuration looks like this:

{
    "configurations": [
        {
            "name": "Debug",
            "type": "lua-local",
            "request": "launch",
            "program": {
              "lua": "lua5.3",
              "file": "${workspaceFolder}/main.lua"
            },
            "env": {
                "LUA_PATH": "./?.lua;/usr/local/Cellar/luarocks/3.2.1/share/lua/5.3/?.lua;/usr/local/share/lua/5.3/?.lua;/usr/local/share/lua/5.3/?/init.lua;/usr/local/lib/lua/5.3/?.lua;/usr/local/lib/lua/5.3/?/init.lua;./?.lua;./?/init.lua;/Users/username/.luarocks/share/lua/5.3/?.lua;/Users/username/.luarocks/share/lua/5.3/?/init.lua"
            }
        }
    ]
}

Now I don't have any problems with local and external lua modules requiring and I don't need to create a separated module for debugger running.

[tomblind]

It looks like LUA_PATH is not being passed to the debug adapter from vscode. Will you try this in your launch.json and see if it works?

"env": {
    "LUA_PATH": "${env:LUA_PATH}"
}

[astrochili]

• Tried "LUA_PATH": "a${env:LUA_PATH}b" in the configuration and It returned no file 'ab'.
• Tried echo $LUA_PATH in the terminal and it returned nothing. Should there be anything?
• Tried print(package.path) in pure Lua in the terminal and it returned /usr/local/share/lua/5.3/?.lua;/usr/local/share/lua/5.3/?/init.lua;/usr/local/lib/lua/5.3/?.lua;/usr/local/lib/lua/5.3/?/init.lua;./?.lua;./?/init.lua. That's a correct path of course, so I placed it to "env": { "LUA_PATH": ... } and it works perfectly for local and luarocks modules.
• Tried print(package.path) in the debugger without any workarounds and it returned only /Users/.../.vscode/extensions/tomblind.local-lua-debugger-vscode-0.1.3/debugger/?.lua.

[tomblind]

Thanks for the exhaustive testing! 😄

It looks like LUA_PATH isn't being used to set package.path. If you don't mind, will you try testing with LUA_PATH_5_3? It's possible that's what your setup is using instead of LUA_PATH.

[astrochili]

Nope, the same situation:

• Tried "LUA_PATH": "a${env:LUA_PATH_5_3}b" in the configuration and It returned no file 'ab'.
• Tried echo $LUA_PATH in the terminal and it returned nothing. Should there be anything?

[tomblind]

In the terminal of vscode or an external one? There should be something in one of those two env variables, because that's where package.path is set from.

[astrochili]

I mean the external system terminal app, not VSCode.

With Lua in the terminal:

• os.getenv("LUA_PATH") -> nil
• os.getenv("LUA_PATH_5_3") -> nil
• LUA_PATH -> nil
• LUA_PATH_5_3 -> nil

With debugger in VSCode:

• os.getenv("LUA_PATH") -> /Users/.../.vscode/extensions/tomblind.local-lua-debugger-vscode-0.1.3/debugger/?.lua
• os.getenv("LUA_PATH_5_3") -> nil
• LUA_PATH -> nil
• LUA_PATH_5_3 -> nil

[tomblind]

Very strange, Lua must be getting its path from somewhere other than the standard env vars.

[tomblind]

On the terminal, can you type declare and see if any env vars reference those paths?

[astrochili]

I typed declare and there are no matches for those paths and nothing with word lua 🤔.

[tomblind]

Well now I'm very confused 😆 It's got to be getting those paths from somewhere.

[astrochili]

Look at this, sounds like Lua get default paths from luaconf.h. And that seems real because it has LUA_PATH_DEFAULT variable with my paths.

[tomblind]

Ah yeah, that's where it's getting the defaults. But how does it find the luarocks modules? You said before those work when running from terminal, right?

[astrochili]

Yeah, it's simple because luarocks installs modules in these paths. For example luarocks module lume has a path /usr/local/share/lua/5.3/lume.lua. I don't know why luarocks path returns such long list of paths but I don't need them, as we see. The default list of paths from luaconf.h is enough.

[tomblind]

Ahhh. Ok. Now it all makes sense 😄

[astrochili]

Yes, in short, the problem is that the debugger doesn't read the standard lua paths from luaconf.h. I don’t know what about LUA_PATH, because I don’t have it, maybe it doesn’t work too.

[Straskal]

"cwd": "${workspaceFolder}" definitely helped with loading assets. Thanks!

And it looks like everything's working! Awesome.