tests: log sendall() operations and port test-http-bad-server.t...
tests: log sendall() operations and port test-http-bad-server.t
Python 3's HTTP server layer buffers output and uses sendall()
instead of write(). In order to make test-http-bad-server.t pass
on Python 3, we needed to teach our socket proxy to log sendall()
events and to abort future sends if we reached our send limit.
The tests using `tail` were difficult to port with inline output
conditionals since the number of lines varied. So we now use
`#if py3` for these tests.
test-http-bad-server.t now passes on Python 3.6 and 3.7 on at
least Linux. However, it does not yet pass on Python 3.5 because
of low-level differences to how the HTTP server is implemented.
Differential Revision:
https://phab.mercurial-scm.org/D5753
