VS Code Not Pausing on Breakpoints in Python After Update

[DenverCoder1]

I've been using debugging in Python for several months with no issues, but today it suddenly stopped working after updating VS Code.

Environment data

• VS Code version: 1.55.2
• Extension version: v2021.3.680753044
• OS and version: Linux x64 5.11.13-arch1-1
• Python version: 3.9.3
• Type of virtual environment used: venv but also with no virtual environment
• Value of the python.languageServer setting: Pylance but same issue with all

Expected behaviour

Debugger should stop on breakpoints and raised exceptions

Actual behaviour

Debugger skips all breakpoints and crashes on raised exceptions

Steps to reproduce:

1. Create a simple module with breakpoints
2. Launch.json

{
  "version": "0.2.0",
  "configurations": [
    {
      "name": "Python: Module",
      "type": "python",
      "request": "launch",
      "module": "bot"
    }
  ]
}

3. Run Python module with F5 / debugger

Screen recording

[abrahammurciano]

Can confirm, this happens to me too. I have the exact same environment data as @DenverCoder1.

I tried to install the python debugger that this extension uses with pip install debugpy, and this command shows the following output:

$ python -m debugpy --version
1.2.1

Then I made the following python script:

# main.py
import debugpy

print("waiting for client")

debugpy.listen(("localhost", 5678))
debugpy.wait_for_client()

print("hello")
debugpy.breakpoint() # I also put a vscode breakpoint here
print("world")

I ran it with python main.py at which point it printed "waiting for client", then I attached the VSCode client with the following launch config. Then it simply printed "hello" and "world" then exited without ever stopping on any breakpoint.

{
	"name": "Python: Remote Attach",
	"type": "python",
	"request": "attach",
	"connect": {
		"host": "localhost",
		"port": 5678
	},
	"pathMappings": [
		{
			"localRoot": "${workspaceFolder}",
			"remoteRoot": "."
		}
	]
}

---

Edit: I'm not sure if this is the right way to do this, or is relevant, but then I tried to run it again with python main.py and then on another terminal I ran python -m debugpy --connect 5678 --pid 23270 and got the following output.

Attaching with arch: i386:x86-64
Running: gdb --nw --nh --nx --pid 23270 --batch --eval-command='set scheduler-locking off' --eval-command='set architecture i386:x86-64' --eval-command='call (void*)dlopen("/home/abraham/.local/lib/python3.9/site-packages/debugpy/_vendored/pydevd/pydevd_attach_to_process/attach_linux_amd64.so", 2)' --eval-command='call (int)DoAttach(0, "import codecs;import json;import sys;decode = lambda s: codecs.utf_8_decode(bytearray(s))[0] if s is not None else None;script_dir = decode([47, 104, 111, 109, 101, 47, 97, 98, 114, 97, 104, 97, 109, 47, 46, 108, 111, 99, 97, 108, 47, 108, 105, 98, 47, 112, 121, 116, 104, 111, 110, 51, 46, 57, 47, 115, 105, 116, 101, 45, 112, 97, 99, 107, 97, 103, 101, 115, 47, 100, 101, 98, 117, 103, 112, 121, 47, 115, 101, 114, 118, 101, 114]);setup = json.loads(decode([123, 34, 109, 111, 100, 101, 34, 58, 32, 34, 99, 111, 110, 110, 101, 99, 116, 34, 44, 32, 34, 97, 100, 100, 114, 101, 115, 115, 34, 58, 32, 91, 34, 49, 50, 55, 46, 48, 46, 48, 46, 49, 34, 44, 32, 53, 54, 55, 56, 93, 44, 32, 34, 119, 97, 105, 116, 95, 102, 111, 114, 95, 99, 108, 105, 101, 110, 116, 34, 58, 32, 102, 97, 108, 115, 101, 44, 32, 34, 108, 111, 103, 95, 116, 111, 34, 58, 32, 110, 117, 108, 108, 44, 32, 34, 97, 100, 97, 112, 116, 101, 114, 95, 97, 99, 99, 101, 115, 115, 95, 116, 111, 107, 101, 110, 34, 58, 32, 110, 117, 108, 108, 125]));sys.path.insert(0, script_dir);import attach_pid_injected;del sys.path[0];attach_pid_injected.attach(setup);", 0)'
Running gdb in target process.
stdout: b'The target architecture is set to "i386:x86-64".\n'
stderr: b'ptrace: Operation not permitted.\nTarget \'None\' cannot support this command.\nNo symbol table is loaded.  Use the "file" command.\nNo symbol table is loaded.  Use the "file" command.\n'

[abrahammurciano]

I tried rolling back to VSCode version 1.55.0 and wiping VSCode data (delete cache, config, extensions, and reinstall) and still no breakpoints work

[MKuranowski]

Same issue here. Seems like a duplicate of #15865 - a bug related to Python 3.9.3.

[karthiknadig]

This was an issue with python 3.9.3. Please Update to python 3.9.4