How to specify working directory to find require'd modules

[michael-uman]

Here is a script I am trying to debug and I encounter an error when stepping over the require line:

-- lesson6 - Michael Uman - Exercise OO programming

-- Added to support local-lua debugger
if os.getenv("LOCAL_LUA_DEBUGGER_VSCODE") == "1" then
    require("lldebugger").start()
end

local r = require("car")

local cars = {
    Car:new("Ford",         "Mustang GT",   2019),
    Car:new("Toyota",       "Camry",        2012),
    Car:new("Chevrolet",    "Camero",       2018),
    Car:new("Dodge",        "Challenger",   2015),
}

-- Sort table by year
table.sort(cars, function (a,b) return a:year() < b:year() end)

for key, value in pairs(cars) do
    value:print();
end

If I execute this code in VSCode local-lua plugin I get the following message when stepping over the require "car" line:

Exception has occurred.
lesson6.lua:5: module 'car' not found:
    no field package.preload['car']
    no file '/home/muman/.vscode-server/extensions/tomblind.local-lua-debugger-vscode-0.1.3/debugger/car.lua'
    no file '/usr/local/lib/lua/5.2/car.so'
    no file '/usr/lib/x86_64-linux-gnu/lua/5.2/car.so'
    no file '/usr/lib/lua/5.2/car.so'
    no file '/usr/local/lib/lua/5.2/loadall.so'
    no file './car.so'

This code executes fine in my WSL environment with the following output:

muman@DESKTOP-BSPUQUB:~/lua-stuff$ lua lesson6.lua 
2012 Toyota       - Camry       
2015 Dodge        - Challenger  
2018 Chevrolet    - Camero      
2019 Ford         - Mustang GT  

My launch.json script is reproduced below:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "lesson6",
            "type": "lua-local",
            "request": "launch",
            "stopOnEntry": true,
            "cwd": "${workspaceFolder}",
            "program": {
                "lua": "lua",
                "file": "${workspaceFolder}/lesson6.lua"
              }
        }
    ]
}

I have tried setting the environment LUA_PATH but can't seem to get it to work.

Is there a solution to this issue?

Thank you, Michael Uman Sr. Software Engineer Wunder-Bar Inc.

[tomblind]

How did you set LUA_PATH? If you set it in the debugger configuration, it should be passed to the program:

{
    "configurations": [
        {
            "name": "lesson6",
            "type": "lua-local",
            "request": "launch",
            "stopOnEntry": true,
            "cwd": "${workspaceFolder}",
            "program": {
                "lua": "lua",
                "file": "${workspaceFolder}/lesson6.lua"
            },
            "environment": {
                "LUA_PATH": "./?.lua"
            }
        }
    ]
}

[michael-uman]

Hello Tom,

Thank you for your prompt reply. You are mostly correct except for the name of the field. It is not 'environment' which needs to be set to ./?.lua but rather env.

I am using VSCode which identifies itself as:

Version: 1.40.1 (system setup)
Commit: 8795a9889db74563ddd43eb0a897a2384129a619
Date: 2019-11-13T16:49:35.976Z
Electron: 6.1.2
Chrome: 76.0.3809.146
Node.js: 12.4.0
V8: 7.6.303.31-electron.0
OS: Windows_NT x64 10.0.18362

I am using WSL lua version 'Lua 5.2.4 Copyright (C) 1994-2015 Lua.org, PUC-Rio'.

Here is the launch.json which works for me now:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "lesson6",
            "type": "lua-local",
            "request": "launch",
            "stopOnEntry": true,
            "cwd": "${workspaceFolder}",
            "program": {
                "lua": "lua",
                "file": "${workspaceFolder}/lesson6.lua"
             },
             "env": {
                 "LUA_PATH": "./?.lua"
             },
        }
    ]
}

Thanks for your support. I am just getting started with Lua for an embedded Lua project and appreciate being able to debug scripts. So far this debug plugin has worked excellently.

Thank you, Michael Uman

[tomblind]

Oops! Sorry I about the wrong name - glad you were able to figure it out.