windows: ensure pure posixfile fd doesn't escape by entering context manager...
windows: ensure pure posixfile fd doesn't escape by entering context manager
There are tests in test-revlog-mmapindex.t and test-rebase-mq-skip.t that are
fixed by this, but we usually don't use --pure on Windows. For whatever reason,
the remaining --pure failures are various errors like $ENOTDIR$ and "Access is
denied" have a trailing '.'.