bpo-37651: Document CancelledError is now a subclass of BaseException (GH-15950)

https://bugs.python.org/issue37651



Automerge-Triggered-By: @1st1
This commit is contained in:
Xtreak 2019-09-11 15:12:51 +01:00 committed by Miss Islington (bot)
parent 97b817eae3
commit 7b69069e9a
1 changed files with 2 additions and 19 deletions

View File

@ -25,26 +25,9 @@ Exceptions
when asyncio Tasks are cancelled. In almost all situations the
exception must be re-raised.
.. important::
.. versionchanged:: 3.8
This exception is a subclass of :exc:`Exception`, so it can be
accidentally suppressed by an overly broad ``try..except`` block::
try:
await operation
except Exception:
# The cancellation is broken because the *except* block
# suppresses the CancelledError exception.
log.log('an error has occurred')
Instead, the following pattern should be used::
try:
await operation
except asyncio.CancelledError:
raise
except Exception:
log.log('an error has occurred')
:exc:`CancelledError` is now a subclass of :class:`BaseException`.
.. exception:: InvalidStateError