[Bug]: Jest debugger does not break on breakpoints

[delroyhiebert]

📝 Description

What's happening?

When debugging Jest tests using the extension the debugger attaches, but does not break/stop at any breakpoints. The test runs to completion

This appears to have broken in V0.4.85 (It was working thru 4.80 up to and including 4.84)

---

🖥️ Environment

Discovered in V0.4.111 but traced back to at least V0.4.85

[firsttris]

Hey, thx for your Report
For me it Breaks on every Breakpoint, so i wonder whats different on your system. But you provided very little information.

Due to the wide variety of project configurations, it is difficult to debug issues without specific details.

[delroyhiebert]

Yeah, I discovered it on my work machine/application which I can share very little of, and was hoping it was just that straightforward.

I will have to do some more analysis if it's not that easy to reproduce.

Multiple people in my organization have reported this issue though, all rectified by reverting to the older versions.

[firsttris]

this are all changes between .84 and .85

90c32cb...58f06aa

investigating....

[firsttris]

maybe you can provide some more information like

Item	Value
Operating System	Windows 11, macOS 14, Ubuntu 22.04
Shell	bash, zsh, PowerShell, cmd, fish
IDE	VSCode, Antigravity, Cursor, Windsurf
VSCode Version	1.100.0 (lowest supported version)

[firsttris]

My Assumption:

The regression was likely caused by a change in how the Jest process is spawned. In v0.85, the extension switched from using the Jest binary to using npx for all execution modes. Using npx (or runtimeExecutable: "npx") spawns a wrapper process, and on some operating systems (likely Windows) the VS Code debugger may fail to attach to the actual Jest worker process, causing breakpoints to be missed.

[firsttris]

vscode-jest-runner-0.4.119.zip

can you check if debugging works with this version?

That would confirm my suspicion.

(you need to rename it to .vsix, remove other extension, drag-and-drop in extension, or right-click install from vscode)

But i think this would break it for other setup again.... binary resolution with npx is much more easy. maybe i could only do it for windows...

[firsttris]

mhhhh i tested on one of my clients project: they use windows 11, powershell 5.1 (which is pretty old). but breakpoints are working well with NPX

so i still dont know which combination of OS/SHELL has problems with not hitting breakpoints

[CoryDanielson]

When I try to debug a test by clicking "Debug" link above the test, it does not hit breakpoints. I will try different versions to see where the regression started.

item	value
OS	Apple M3 Max - 15.7.3 (24G419)
Shell	zsh
IDE	VSCode 1.108.2 (Universal)

VS Code Info

Version: 1.108.2 (Universal)
Commit: c9d77990917f3102ada88be140d28b038d1dd7c7
Date: 2026-01-21T13:52:09.270Z
Electron: 39.2.7
ElectronBuildId: 12953945
Chromium: 142.0.7444.235
Node.js: 22.21.1
V8: 14.2.231.21-electron.0
OS: Darwin arm64 24.6.0

[CoryDanielson]

firsttris, the issue appears to have started in version 0.4.93. Downgrading to 0.4.92 is a workaround for now.

version	hit breakpoint ?
0.4.113	❌
0.4.109	❌
0.4.104	❌
0.4.94	❌
0.4.93	❌
0.4.92	✅
0.4.91	✅
0.4.90	✅
0.4.87	✅
0.4.86	✅

0.4.93 script - ❌

/usr/bin/env 'NODE_OPTIONS= --require "/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/ms-vscode.js-debug/src/bootloader
.js"  --inspect-publish-uid=http' 'VSCODE_INSPECTOR_OPTIONS=:::{"inspectorIpc":"/var/folders/rr/d_sh25m931d68dmxhckl7htm0000gn/T/node-cdp.54428-86ac091e-5.sock","deferredMode":false,"waitForDebugger":"","e
xecPath":"/Users/USER_DIR/.nvm/versions/node/v24.11.0/bin/node","onlyEntrypoint":false,"autoAttachMode":"always","fileCallback":"/var/folders/rr/d_sh25m931d68dmxhckl7htm0000gn/T/node-debug-callback-6f
00294eabb0ef8e"}' /Users/USER_DIR/.nvm/versions/node/v24.11.0/bin/node .yarn/releases/yarn-1.22.18.cjs jest /Users/USER_DIR/code/MY-REPO/PATH/TO/TEST/__tests__/SOME-FILE\\
.test\\.tsx -c /Users/USER_DIR/code/MY-REPO/jest.config.js -t the\ title\ of\ my\ it\ statement

0.4.92 script ✅

/usr/bin/env 'NODE_OPTIONS= --require "/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/ms-vscode.js-debug/src/bootloader.js"  --inspect-publish-uid=http' 'VSCODE_IN
SPECTOR_OPTIONS=:::{"inspectorIpc":"/var/folders/rr/d_sh25m931d68dmxhckl7htm0000gn/T/node-cdp.54428-7b29e2f9-13.sock","deferredMode":false,"waitForDebugger":"","execPath":"/Users/USER_DIR/.nvm/version
s/node/v24.11.0/bin/node","onlyEntrypoint":false,"autoAttachMode":"always","fileCallback":"/var/folders/rr/d_sh25m931d68dmxhckl7htm0000gn/T/node-debug-callback-1452e834f8c29c0a"}' /Users/USER_DIR/.nvm
/versions/node/v24.11.0/bin/node .yarn/releases/yarn-1.22.18.cjs jest /Users/USER_DIR/code/MY-REPO/PATH/TO/TEST/__tests__/SOME-FILE\\.test\\.tsx -c /Users/USER_DIR/code/MY
-REPO/jest.config.js -t the\ title\ of\ my\ it\ statement

[delroyhiebert]

Item	Value
Operating System	Windows 11
Shell	PowerShell
IDE	VSCode
VSCode Version	1.108.2
Node version	22.21.1

I apologize for not getting back right away and I appreciate your investigation @firsttris

I'll try and fine time to run the zip version today or tomorrow

[CoryDanielson]

Item Value
Operating System Windows 11
Shell PowerShell
IDE VSCode
VSCode Version 1.108.2
Node version 22.21.1
I apologize for not getting back right away and I appreciate your investigation @firsttris

I'll try and fine time to run the zip version today or tomorrow

@delroyhiebert in VS code, if you go to the extension and click the Gear icon, you can hit "Install Specific Version..." and select different versions to try out. Once installed, click "Restart Extensions" and try to run the test again.

[firsttris]

for me its not clear, why for most people its working, but for you both its not hitting any breakpoints.

for me it works even on windows with powershell 5.1 and i think more people would have complained if it was not working on OSX.

[firsttris]

i continue to investigate this

[CoryDanielson]

When I launch Debug Jest from my launch.json config, it will hit breakpoints. I'm not sure if this output helps at all

doesnt work - clicking debug

/usr/bin/env 'NODE_OPTIONS= --require "/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/ms-vscode.js-debug/src/bootloader.js"  --inspect-publish-uid=http' 'VSCODE_IN
SPECTOR_OPTIONS=:::{"inspectorIpc":"/var/folders/rr/d_sh25m931d68dmxhckl7htm0000gn/T/node-cdp.93559-e5eab55e-1.sock","deferredMode":false,"waitForDebugger":"","execPath":"/Users/USER-DIR/.nvm/versions
/node/v24.11.0/bin/node","onlyEntrypoint":false,"autoAttachMode":"always","fileCallback":"/var/folders/rr/d_sh25m931d68dmxhckl7htm0000gn/T/node-debug-callback-69f3d733eed9f4db"}' /Users/USER-DIR/.nvm/
versions/node/v24.11.0/bin/node .yarn/releases/yarn-1.22.18.cjs jest /Users/USER-DIR/code/MY-REPO/PATH/TO/MY/__tests__/TEST-FILE\\.test\\.tsx -c /Users/USER-DIR/code/MY-REPO/jest.config.js -t step-two\ getCurrentStep\ routing\ does\ not\ respect\ forced\ step\ if\ step\ is\ not\ in\ allow\ list 

works - clicking Debug Jest

/usr/bin/env NODE_ENV=testDebug 'NODE_OPTIONS= --require "/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/ms-vscode.js-debug/src/bootloader.js"  --inspect-publish-u
id=http' 'VSCODE_INSPECTOR_OPTIONS=:::{"inspectorIpc":"/var/folders/rr/d_sh25m931d68dmxhckl7htm0000gn/T/node-cdp.93559-0b586406-5.sock","deferredMode":false,"waitForDebugger":"","execPath":"/Users/USER-
DIR/.nvm/versions/node/v24.11.0/bin/node","onlyEntrypoint":false,"autoAttachMode":"always","fileCallback":"/var/folders/rr/d_sh25m931d68dmxhckl7htm0000gn/T/node-debug-callback-60e2ae3f1022e4fa"}' /Users/
USER-DIR/.nvm/versions/node/v24.11.0/bin/node --nolazy ./node_modules/.bin/jest /Users/USER-DIR/code/MY-REPO/PATH/TO/MY/__tests__/TEST-FILE.test.tsx --runInBand --update
Snapshot --verbose 

Here's my launch.json config for "Debug Jest"

{
	"name": "Debug Jest",
	"type": "node",
	"request": "launch",
	"program": "${workspaceRoot}/node_modules/.bin/jest",
	"stopOnEntry": false,
	"args": ["${file}", "--runInBand", "--updateSnapshot", "--verbose"],
	"cwd": "${workspaceRoot}",
	"preLaunchTask": null,
	"runtimeExecutable": null,
	"runtimeArgs": ["--nolazy"],
	"env": {
		"NODE_ENV": "testDebug"
	},
	"console": "integratedTerminal",
	"sourceMaps": true,
	"outFiles": []
},