generator throw delivered to incorrect generator under trace #105162
Description
Bug report
With the following demo code, a subgenerator yield from from a parent generator main(), that catches exceptions and returns "good":
class Inner:
def send(self, v):
return None
def __iter__(self):
return self
def __next__(self):
return self.send(None)
def throw(self, *exc_info):
raise StopIteration("good")
def main():
return (yield from Inner())
def run(coro):
coro.send(None)
try:
coro.throw(Exception)
except StopIteration as e:
print(e.value)
run(main())when run with python -m trace, the exception is delivered to the outer generator main() instead of being suppressed
graingert@conscientious ~/projects/cpython main ./python -m trace --count -C . demo.py
Traceback (most recent call last):
File "<frozen runpy>", line 198, in _run_module_as_main
File "<frozen runpy>", line 88, in _run_code
File "/home/graingert/projects/cpython/Lib/trace.py", line 741, in <module>
main()
File "/home/graingert/projects/cpython/Lib/trace.py", line 729, in main
t.runctx(code, globs, globs)
File "/home/graingert/projects/cpython/Lib/trace.py", line 451, in runctx
exec(cmd, globals, locals)
File "demo.py", line 26, in <module>
run(main())
File "demo.py", line 21, in run
coro.throw(Exception)
File "demo.py", line 16, in main
return (yield from Inner())
^^^^^^^^^^^^^^^^^^
Exception
✘ graingert@conscientious ~/projects/cpython main ± ./python demo.py
good
the problem also occurs with the equivalent generator syntax, eg:
def Inner():
try:
while True:
yield None
except:
return "good"Your environment
- CPython versions tested on: c05c31d 3.12b1
- Operating system and architecture: Ubuntu 22.04 x86_64
see also
urllib3/urllib3#3049 (comment)
nedbat/coveragepy#1635