Step Over, Step Into, not working when debugging Subprocesses

[maor-outrival]

When debugging a process in python, the program halts on breakpoints yet only the Continue button works. Pressing Step Over or Step into just Continues to the next breakpoint.

I have tried many launch.json configs and the only thing that resolved my issue was downgrading to v2024.10.0.

here is my config just in case:

    {
        "name": "Python Debugger: Current File",
        "type": "debugpy",
        "request": "launch",
        "program": "app/main.py",
        "console": "integratedTerminal",
        "env": {
            "PYTHONPATH": "${workspaceFolder}"
        },
        "justMyCode": true,
        "subProcess": true,
        "steppingResumesAllThreads": false
    },

[rchiodo]

Can you share your application? This works fine for me with the latest bits.

DebugStepMultiproc.mp4

I used this code here:

import subprocess
import sys
import time

def act_busy():
    # Simulate a busy operation
    print("Subprocess is busy doing something...")
    for i in range(500):
        print(f"Working... {i + 1}/5")
        sys.stdout.flush()  # Ensure the output is flushed immediately
        time.sleep(1)  # Simulate work with a sleep

    print("Subprocess finished working.")

def run_subprocess():
    # Define the command to run as a subprocess
    command = ['python', __file__, 'act_busy']

    try:
        # Run the subprocess and wait for it to complete
        result = subprocess.run(command, capture_output=True, text=True, check=True)
        
        # Print the output of the subprocess
        print(result.stdout)
        
        # Print success message
        print("Subprocess completed successfully.")
    except subprocess.CalledProcessError as e:
        # Print error message if the subprocess fails
        print(f"Subprocess failed with error: {e}")

if __name__ == "__main__":
    if len(sys.argv) > 1:
        act_busy()
    else:
        run_subprocess()

[github-actions]

This issue was closed because it has been stalled for 30 days with no activity. If the issue still persists, please reopen with the information requested. Thanks.

[SobhanMP]

It's broken, see the following

import time
import multiprocessing as mp

def f():
    for i in range(10):
        time.sleep(1)
        print(i)

if __name__ == "__main__":
    p = mp.Process(target=f)
    p.start()
    p.join()

[rchiodo]

Seems to work fine for me. Although I'm on windows.

DebugMultiproc.mp4

[rchiodo]

I can reproduce on Linux though.

[rchiodo]

Strange but the subprocess example works fine on Linux. Not sure how multiprocess could affect stepping.