Debug with VSCode

[manikantag]

Please describe your issue:
Unable to start/debug the app using VSCode.

Console output when you run electron-forge with the environment variable DEBUG=electron-forge:*. (Instructions on how to do so here. Please include the stack trace if one exists.

With below launch.json configuration,

"configurations": [
	{
	    "name": "Launch Program",
	    "type": "node",
	    "request": "launch",
	    "runtimeExecutable": "${workspaceRoot}/node_modules/.bin/electron.cmd",
	    "program": "${workspaceRoot}/es6-init.js",
	    "cwd": "${workspaceRoot}"
	}
]

I m getting below error:

c:\eapp/node_modules/.bin/electron.cmd --debug-brk=21609 --nolazy es6-init.js 

App threw an error duri
ng load
Error: Cannot fi
nd module 'c:\eapp\--debug-brk=21609'
    at Module._resolveFilename (module.js:455:15)
    at Function.Module._resolveFilename (c:\eapp\node_modules\electron-prebuilt-compile\node_modules\electron\dist\resources\electron.asar\common\reset-search-paths.js:35:12)

With below launch.json configuration,

"configurations": [
	{
	    "name": "Launch Program",
	    "type": "node",
	    "request": "launch",
	    "runtimeExecutable": "${workspaceRoot}/node_modules/.bin/electron-forge.cmd",
	    "cwd": "${workspaceRoot}",
	    "args": [
	        "start"
	    ]
	}
]

I m getting below error:

c:\eapp/node_modules/.bin/electron-forge.cmd --debug-brk=41000 --nolazy start 
√ Checking your System
  error: unknown option `--debug-brk'

What command line arguments are you passing?

Can be seen in above section

What does your config.forge data in package.json look like?

"forge": {
    "make_targets": {
        "win32": ["squirrel"],
        "darwin": ["zip"],
        "linux": ["deb","rpm"]
    },
    "electronPackagerConfig": {
        "ignore": [
            "node_modules/sqlite3/build",
            "node_modules/sqlite3/deps",
            "node_modules/sqlite3/src"
        ]
    },
    "electronWinstallerConfig": {
        "name": "eapp",
        "loadingGif": "./assets/img/install-splash.png",
        "iconUrl": "http://manikanta.com/favicon.ico",
        "setupIcon": "./assets/img/icon.ico",
        "noMsi": true
    },
    "electronInstallerDebian": {},
    "electronInstallerRedhat": {}
}

Can you please let me how to configure properly? Thanks.

[MarshallOfSound]

error: unknown option `--debug-brk'

This is because electron-forge expects your command to be

electron-forge start --debug-brk=41000 --nolazy

You should go ask on the VS Code repository how to make the node debug arguments appear after your custom arguments (["start"])

[manikantag]

I've tried the same, but still getting error (ran from cmd prompt):

C:\eapp>electron-forge start --debug-brk=41000
√ Checking your System
- Locating Application
  error: unknown option `--debug-brk'

By the way, thanks for the tip about VSCode. I got some clues from microsoft/vscode#16173.

Below is how I've configured VSCode:

"configurations": [
    {
        "name": "Launch Program",
        "type": "node",
        "request": "launch",
        "runtimeExecutable": "${workspaceRoot}/node_modules/.bin/electron-forge.cmd",
        "port": 41000,
        "runtimeArgs": [
            "start",
            "--debug-brk=41000",
            "--nolazy"
        ],
        "cwd": "${workspaceRoot}"
    }
]

[MarshallOfSound]

What version of electron forge are you using? The latest version definitely shouldn't throw that error

[manikantag]

Now I've switched to 2.2.0, and things are different now.

When I didn't pass --debug-brk switch, app is starting more than one electron process and app window is launching.

c:\eapp>node_modules\.bin\electron-forge.cmd start
√ Checking your System
√ Locating Application
√ Preparing native dependencies 1/1
√ Launching Application

But when I pass --debug-brk, only one electron process is starting and no visible window is launched. But the command o/p is same though.

c:\eapp>node_modules\.bin\electron-forge.cmd start --debug-brk=41000
√ Checking your System
√ Locating Application
√ Preparing native dependencies 1/1
√ Launching Application

[MarshallOfSound]

I am unfamiliar with the fine art of attaching a debugger to the main Electron process and this isn't really an issue with electron-forge rather a usage question regarding Electron itself which can be summarised as.

"How can I debug the main process of Electron?"

A good guide exists in the Electron repository.

https://github.com/electron/electron/blob/master/docs/tutorial/debugging-main-process-vscode.md

If that guide doesn't work you can ask for help in the Electron community or Slack Channel.

[manikantag]

I think I m not clear enough. All the above output is from running the app from command line. No VSCode here :)

[MarshallOfSound]

@manikantag Everything after the word start in that command is simply passed through to the electron command.

c:\eapp>node_modules\.bin\electron-forge.cmd start --debug-brk=41000

Is exactly the same as

c:\eapp>node_modules\.bin\electron.cmd . --debug-brk=41000

Therefore if that command doesn't do what you expect it to do or you can't figure out what the syntax is that you want, you need to ask over at the Electron community / slack areas. The electron-forge issues section hopefully is to remain for forge specific issues 👍

[enlight]

But when I pass --debug-brk, only one electron process is starting and no visible window is launched.

This is to be expected, --debug-brk means "attach the debugger and pause execution on program entry", so the main process of your app is paused on startup waiting for you to step/continue execution via the debugger. When you do continue execution the main process will then go on and create all the other processes (renderer, GPU, etc.). If you don't want your app to pause on entry then use the --debug flag.

By the way, VSCode debug configurations have a boolean property called stopOnEntry that toggles this --debug-brk flag.

[manikantag]

@enlight Yeah, I've figured it out. Now I m using 'Attach' mode to run the app. Somehow I m having issues with 'Launch' mode.

[manikantag]

All this confusion is because even though I've mentioned --debug=41000, but still electron is starting 5858 as debug port and thus VSCode is not able to attach to the port=41000 specified in launch.json.

Below is the command line args of the app process tree.

Parent node process is having correct command line args: (--debug=41000)

Child node process is having incorrect command line args: (--debug 41000) (mind the missing =)

Now I've changed to port=5858 in VSCode's launch.json and is attaching properly.

But I m not sure why it is like this :(