bpo-30980: Fix double close in asyncore.file_wrapper (#2789)
* bpo-30980: Fix close test to fail
test_close_twice was not considering the fact that file_wrapper is
duping the file descriptor. Closing the original descriptor left the
duped one open, hiding the fact that close protection is not effective.
* bpo-30980: Fix double close protection
Invalidated self.fd before closing, handling correctly the case when
os.close raises.
* bpo-30980: Fix fd leak introduced in the fixed test
2 files changed