Next.js: VSCode Debugging broke after upgrading from version 9.2.2 to 9.3.0

[chadalen]

Bug report

Debugging through VSCode no longer works

Describe the bug

When running debugger through VSCode console after upgrading from version 9.2.2 to 9.30 the console spams
"Starting inspector on 127.0.0.1:9229 failed: address already in use" but the address is not in use.

baydash on master [!] is 📦 v1.0.0 via ⬢ v12.13.0 on ☁️  us-east-2 
❯  cd /Users/crazypanda/Workspaces/baydash ; env NODE_OPTIONS=--inspect-brk /usr/local/bin/node node_modules/.bin/next 
Debugger listening on ws://127.0.0.1:9229/61643430-1b26-4c6b-864e-6413d4daf6b9
For help, see: https://nodejs.org/en/docs/inspector
Debugger attached.
[ wait ]  starting the development server ...
[ info ]  waiting on http://localhost:3000 ...
Starting inspector on 127.0.0.1:9229 failed: address already in use
Starting inspector on 127.0.0.1:9229 failed: address already in use
Starting inspector on 127.0.0.1:9229 failed: address already in use
Starting inspector on 127.0.0.1:9229 failed: address already in use

To Reproduce

1. Use Next.js version 9.3.0
2. Create a Next.js app
3. Create a launch.json file (for VSCode)

{
    "version": "0.2.0",
    "configurations": [
        {
            "type": "node",
            "request": "launch",
            "name": "Debug App",
            "program": "${workspaceFolder}/node_modules/.bin/next",
            "port": 9229,
            "console": "integratedTerminal",
            "cwd": "${workspaceFolder}",
            "env": {
                "NODE_OPTIONS": "--inspect-brk"
            }
        }
    ]
}

In VSCode run the debugger

Expected behavior

Should not say "Starting inspector on 127.0.0.1:9229 failed: address already in use". The server should run and you should be able to set breakpoints in VSCode.

System information

• OS: MacOS
• Browser (if applies) Microsoft Edge (Chromium)
• Version of Next.js: 9.3.0

Additional context

This does not happen in version 9.2.2

[pecoram]

any news about this issue?

[chadalen]

@pecoram Here's a related issue #11030

PR: https://github.com/zeit/next.js/pull/10807

[chadalen]

Going to close this ticket. I was able to get debugging in VSCode working by removing --inspect-brk. Seems like Next version 9.3.1 calls --inspect under the hood. See https://github.com/zeit/next.js/issues/11030#issuecomment-598622967

This VSCode launch.json works for me.

{
    "version": "0.2.0",
    "configurations": [
        {
            "type": "node",
            "request": "launch",
            "name": "Debug App",
            "program": "${workspaceFolder}/node_modules/.bin/next",
            "console": "integratedTerminal",
            "cwd": "${workspaceFolder}"
        }
    ]
}

[haneatic]

@chadalen and what do I do if I use TypeScript? Placing a breakpoint shows a warning that SourceMaps aren't found. Using "sourceMap": true didn't help

[JoseFMP]

Same issue here. Wondering, any plans to fix this?