concurrent.interpreters subinterpreters stdout wrong #17158
Description
Environment data
- VS Code version: 1.105.1
- Jupyter Extension version (available under the Extensions sidebar): 2025.9.1
- Python Extension version (available under the Extensions sidebar): 2025.18.0
- OS (Windows | Mac | Linux distro) and version: win10 21H2
- Python and/or Anaconda version: 3.14
- Type of virtual environment used: N/A
- Jupyter server running: Local
Expected behaviour
prints all 5 spam!s, like in ipython.
Actual behaviour
only spam!4 was printed
Steps to reproduce:
run below example codes from https://docs.python.org/3/library/concurrent.interpreters.html
from concurrent import interpreters
interp = interpreters.create()
# Run in the current OS thread.
interp.exec('print("spam!1")')
interp.exec("""if True:
print('spam!2')
""")
from textwrap import dedent
interp.exec(dedent("""
print('spam!3')
"""))
def run(arg):
return arg
res = interp.call(run, 'spam!4')
print(res)
def run():
print('spam!5')
interp.call(run)
# Run in new OS thread.
t = interp.call_in_thread(run)
t.join()