view tests/test-http-bad-server.t @ 35569:964212780daf

rust: implementation of `hg`

This commit provides a mostly-working implementation of the
`hg` script in Rust along with scaffolding to support Rust in
the repository.

If you are familiar with Rust, the contents of the added rust/
directory should be pretty straightforward. We create an "hgcli"
package that implements a binary application to run Mercurial.
The output of this package is an "hg" binary.

Our Rust `hg` (henceforth "rhg") essentially is a port of the existing
`hg` Python script. The main difference is the creation of the embedded
CPython interpreter is handled by the binary itself instead of relying
on the shebang. In that sense, rhg is more similar to the "exe wrapper"
we currently use on Windows. However, unlike the exe wrapper, rhg does
not call the `hg` Python script. Instead, it uses the CPython APIs to
import mercurial modules and call appropriate functions. The amount of
code here is surprisingly small.

It is my intent to replace the existing C-based exe wrapper with rhg.
Preferably in the next Mercurial release. This should be achievable -
at least for some Mercurial distributions. The future/timeline for
rhg on other platforms is less clear. We already ship a hg.exe on
Windows. So if we get the quirks with Rust worked out, shipping a
Rust-based hg.exe should hopefully not be too contentious.

Now onto the implementation.

We're using python27-sys and the cpython crates for talking to the
CPython API. We currently don't use too much functionality of the
cpython crate and could have probably cut it out. However, it does
provide a reasonable abstraction over unsafe {} CPython function
calls. While we still have our fair share of those, at least we're
not dealing with too much refcounting, error checking, etc. So I
think the use of the cpython crate is justified. Plus, there is
not-yet-implemented functionality that could benefit from cpython. I
see our use of this crate only increasing.

The cpython and python27-sys crates are not without their issues.
The cpython crate didn't seem to account for the embedding use case
in its design. Instead, it seems to assume that you are building
a Python extension. It is making some questionable decisions around
certain CPython APIs. For example, it insists that
PyEval_ThreadsInitialized() is called and that the Python code
likely isn't the main thread in the underlying application. It
is also missing some functionality that is important for embedded
use cases (such as exporting the path to the Python interpreter
from its build script). After spending several hours trying to
wrangle python27-sys and cpython, I gave up and forked the project
on GitHub. Our Cargo.toml tracks this fork. I'm optimistic that
the upstream project will accept our contributions and we can
eventually unfork.

There is a non-trivial amount of code in our custom Cargo build
script. Our build.rs (which is called as part of building the hgcli
crate):

* Validates that the Python interpreter that was detected by the
  python27-sys crate provides a shared library (we only support
  shared library linking at this time - although this restriction
  could be loosened).
* Validates that the Python is built with UCS-4 support. This ensures
  maximum Unicode compatibility.
* Exports variables to the crate build allowing the built crate to e.g.
  find the path to the Python interpreter.

The produced rhg should be considered alpha quality. There are several
known deficiencies. Many of these are documented with inline TODOs.

Probably the biggest limitation of rhg is that it assumes it is
running from the ./rust/target/<target> directory of a source
distribution. So, rhg is currently not very practical for real-world
use. But, if you can `cargo build` it, running the binary *should*
yield a working Mercurial CLI.

In order to support using rhg with the test harness, we needed to hack
up run-tests.py so the path to Mercurial's Python files is set properly.
The change is extremely hacky and is only intended to be a stop-gap
until the test harness gains first-class support for installing rhg.
This will likely occur after we support running rhg outside the
source directory.

Despite its officially alpha quality, rhg copes extremely well with
the test harness (at least on Linux). Using
`run-tests.py --with-hg ../rust/target/debug/hg`, I only encounter
the following failures:

* test-run-tests.t -- Warnings emitted about using an unexpected
  Mercurial library. This is due to the hacky nature of setting the
  Python directory when run-tests.py detected rhg.
* test-devel-warnings.t -- Expected stack trace missing frame for `hg`
  (This is expected since we no longer have an `hg` script!)
* test-convert.t -- Test running `$PYTHON "$BINDIR"/hg`, which obviously
  assumes `hg` is a Python script.
* test-merge-tools.t -- Same assumption about `hg` being executable with
  Python.
* test-http-bad-server.t -- Seeing exit code 255 instead of 1 around
  line 358.
* test-blackbox.t -- Exit code 255 instead of 1.
* test-basic.t -- Exit code 255 instead of 1.

It certainly looks like we have a bug around exit code handling. I
don't think it is severe enough to hold up review and landing of this
initial implementation. Perfect is the enemy of good.

Differential Revision: https://phab.mercurial-scm.org/D1581

#require killdaemons serve zstd

Client version is embedded in HTTP request and is effectively dynamic. Pin the
version so behavior is deterministic.

  $ cat > fakeversion.py << EOF
  > from mercurial import util
  > util.version = lambda: '4.2'
  > EOF

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > fakeversion = `pwd`/fakeversion.py
  > [devel]
  > legacy.exchange = phases
  > EOF

  $ hg init server0
  $ cd server0
  $ touch foo
  $ hg -q commit -A -m initial

Also disable compression because zstd is optional and causes output to vary
and because debugging partial responses is hard when compression is involved

  $ cat > .hg/hgrc << EOF
  > [extensions]
  > badserver = $TESTDIR/badserverext.py
  > [server]
  > compressionengines = none
  > EOF

Failure to accept() socket should result in connection related error message

  $ hg serve --config badserver.closebeforeaccept=true -p $HGPORT -d --pid-file=hg.pid
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  abort: error: $ECONNRESET$
  [255]

(The server exits on its own, but there is a race between that and starting a new server.
So ensure the process is dead.)

  $ killdaemons.py $DAEMON_PIDS

Failure immediately after accept() should yield connection related error message

  $ hg serve --config badserver.closeafteraccept=true -p $HGPORT -d --pid-file=hg.pid
  $ cat hg.pid > $DAEMON_PIDS

TODO: this usually outputs good results, but sometimes emits abort:
error: '' on FreeBSD and OS X.
What we ideally want are:

abort: error: $ECONNRESET$

The flakiness in this output was observable easily with
--runs-per-test=20 on macOS 10.12 during the freeze for 4.2.
  $ hg clone http://localhost:$HGPORT/ clone
  abort: error: * (glob)
  [255]

  $ killdaemons.py $DAEMON_PIDS

Failure to read all bytes in initial HTTP request should yield connection related error message

  $ hg serve --config badserver.closeafterrecvbytes=1 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  abort: error: bad HTTP status line: ''
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(1 from 65537) -> (1) G
  read limit reached; closing socket

  $ rm -f error.log

Same failure, but server reads full HTTP request line

  $ hg serve --config badserver.closeafterrecvbytes=40 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS
  $ hg clone http://localhost:$HGPORT/ clone
  abort: error: bad HTTP status line: ''
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(40 from 65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(7 from -1) -> (7) Accept-
  read limit reached; closing socket

  $ rm -f error.log

Failure on subsequent HTTP request on the same socket (cmd?batch)

  $ hg serve --config badserver.closeafterrecvbytes=210 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS
  $ hg clone http://localhost:$HGPORT/ clone
  abort: error: bad HTTP status line: ''
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(210 from 65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(177 from -1) -> (27) Accept-Encoding: identity\r\n
  readline(150 from -1) -> (35) accept: application/mercurial-0.1\r\n
  readline(115 from -1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(9? from -1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n (glob)
  readline(4? from -1) -> (2) \r\n (glob)
  write(36) -> HTTP/1.1 200 Script output follows\r\n
  write(23) -> Server: badhttpserver\r\n
  write(37) -> Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41) -> Content-Type: application/mercurial-0.1\r\n
  write(21) -> Content-Length: 417\r\n
  write(2) -> \r\n
  write(417) -> lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps unbundle=HG10GZ,HG10BZ,HG10UN httpheader=1024 httpmediatype=0.1rx,0.1tx,0.2tx compression=none
  readline(4? from 65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n (glob)
  readline(1? from -1) -> (1?) Accept-Encoding* (glob)
  read limit reached; closing socket
  readline(210 from 65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n
  readline(184 from -1) -> (27) Accept-Encoding: identity\r\n
  readline(157 from -1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(128 from -1) -> (41) x-hgarg-1: cmds=heads+%3Bknown+nodes%3D\r\n
  readline(87 from -1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(39 from -1) -> (35) accept: application/mercurial-0.1\r\n
  readline(4 from -1) -> (4) host
  read limit reached; closing socket

  $ rm -f error.log

Failure to read getbundle HTTP request

  $ hg serve --config badserver.closeafterrecvbytes=304 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS
  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  abort: error: bad HTTP status line: ''
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(1 from -1) -> (1) x (?)
  readline(1 from -1) -> (1) x (?)
  readline(304 from 65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(271 from -1) -> (27) Accept-Encoding: identity\r\n
  readline(244 from -1) -> (35) accept: application/mercurial-0.1\r\n
  readline(209 from -1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(18? from -1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n (glob)
  readline(13? from -1) -> (2) \r\n (glob)
  write(36) -> HTTP/1.1 200 Script output follows\r\n
  write(23) -> Server: badhttpserver\r\n
  write(37) -> Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41) -> Content-Type: application/mercurial-0.1\r\n
  write(21) -> Content-Length: 417\r\n
  write(2) -> \r\n
  write(417) -> lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps unbundle=HG10GZ,HG10BZ,HG10UN httpheader=1024 httpmediatype=0.1rx,0.1tx,0.2tx compression=none
  readline(13? from 65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n (glob)
  readline(1?? from -1) -> (27) Accept-Encoding: identity\r\n (glob)
  readline(8? from -1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n (glob)
  readline(5? from -1) -> (41) x-hgarg-1: cmds=heads+%3Bknown+nodes%3D\r\n (glob)
  readline(1? from -1) -> (1?) x-hgproto-1:* (glob)
  read limit reached; closing socket
  readline(304 from 65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n
  readline(278 from -1) -> (27) Accept-Encoding: identity\r\n
  readline(251 from -1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(222 from -1) -> (41) x-hgarg-1: cmds=heads+%3Bknown+nodes%3D\r\n
  readline(181 from -1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(133 from -1) -> (35) accept: application/mercurial-0.1\r\n
  readline(98 from -1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(7? from -1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n (glob)
  readline(2? from -1) -> (2) \r\n (glob)
  write(36) -> HTTP/1.1 200 Script output follows\r\n
  write(23) -> Server: badhttpserver\r\n
  write(37) -> Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41) -> Content-Type: application/mercurial-0.1\r\n
  write(20) -> Content-Length: 42\r\n
  write(2) -> \r\n
  write(42) -> 96ee1d7354c4ad7372047672c36a1f561e3a6a4c\n;
  readline(2? from 65537) -> (2?) GET /?cmd=getbundle HTTP* (glob)
  read limit reached; closing socket
  readline(304 from 65537) -> (30) GET /?cmd=getbundle HTTP/1.1\r\n
  readline(274 from -1) -> (27) Accept-Encoding: identity\r\n
  readline(247 from -1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(218 from -1) -> (218) x-hgarg-1: bookmarks=1&bundlecaps=HG20%2Cbundle2%3DHG20%250Abookmarks%250Achangegroup%253D01%252C02%250Adigests%253Dmd5%252Csha1%252Csha512%250Aerror%253Dabort%252Cunsupportedcontent%252Cpushraced%252Cpushkey%250Ahgtag
  read limit reached; closing socket

  $ rm -f error.log

Now do a variation using POST to send arguments

  $ hg serve --config experimental.httppostargs=true --config badserver.closeafterrecvbytes=315 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  abort: error: bad HTTP status line: ''
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(315 from 65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(282 from -1) -> (27) Accept-Encoding: identity\r\n
  readline(255 from -1) -> (35) accept: application/mercurial-0.1\r\n
  readline(220 from -1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(19? from -1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n (glob)
  readline(14? from -1) -> (2) \r\n (glob)
  write(36) -> HTTP/1.1 200 Script output follows\r\n
  write(23) -> Server: badhttpserver\r\n
  write(37) -> Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41) -> Content-Type: application/mercurial-0.1\r\n
  write(21) -> Content-Length: 430\r\n
  write(2) -> \r\n
  write(430) -> lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps unbundle=HG10GZ,HG10BZ,HG10UN httpheader=1024 httppostargs httpmediatype=0.1rx,0.1tx,0.2tx compression=none
  readline\(14[67] from 65537\) -> \(2[67]\) POST /\?cmd=batch HTTP/1.1\\r\\n (re)
  readline\(1(19|20) from -1\) -> \(27\) Accept-Encoding: identity\\r\\n (re)
  readline(9? from -1) -> (41) content-type: application/mercurial-0.1\r\n (glob)
  readline(5? from -1) -> (19) vary: X-HgProto-1\r\n (glob)
  readline(3? from -1) -> (19) x-hgargs-post: 28\r\n (glob)
  readline(1? from -1) -> (1?) x-hgproto-1: * (glob)
  read limit reached; closing socket
  readline(315 from 65537) -> (27) POST /?cmd=batch HTTP/1.1\r\n
  readline(288 from -1) -> (27) Accept-Encoding: identity\r\n
  readline(261 from -1) -> (41) content-type: application/mercurial-0.1\r\n
  readline(220 from -1) -> (19) vary: X-HgProto-1\r\n
  readline(201 from -1) -> (19) x-hgargs-post: 28\r\n
  readline(182 from -1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(134 from -1) -> (35) accept: application/mercurial-0.1\r\n
  readline(99 from -1) -> (20) content-length: 28\r\n
  readline(79 from -1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(5? from -1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n (glob)
  readline(? from -1) -> (2) \r\n (glob)
  read(? from 28) -> (?) cmds=* (glob)
  read limit reached, closing socket
  write(36) -> HTTP/1.1 500 Internal Server Error\r\n

  $ rm -f error.log

Now move on to partial server responses

Server sends a single character from the HTTP response line

  $ hg serve --config badserver.closeaftersendbytes=1 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  abort: error: bad HTTP status line: H
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(1 from 36) -> (0) H
  write limit reached; closing socket
  write(36) -> HTTP/1.1 500 Internal Server Error\r\n

  $ rm -f error.log

Server sends an incomplete capabilities response body

  $ hg serve --config badserver.closeaftersendbytes=180 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  abort: HTTP request error (incomplete response; expected 397 bytes got 20)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (144) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (121) Server: badhttpserver\r\n
  write(37 from 37) -> (84) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (43) Content-Type: application/mercurial-0.1\r\n
  write(21 from 21) -> (22) Content-Length: 417\r\n
  write(2 from 2) -> (20) \r\n
  write(20 from 417) -> (0) lookup changegroupsu
  write limit reached; closing socket

  $ rm -f error.log

Server sends incomplete headers for batch request

  $ hg serve --config badserver.closeaftersendbytes=695 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

TODO this output is horrible

  $ hg clone http://localhost:$HGPORT/ clone
  abort: 'http://localhost:$HGPORT/' does not appear to be an hg repository:
  ---%<--- (applicat)
  
  ---%<---
  !
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (659) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (636) Server: badhttpserver\r\n
  write(37 from 37) -> (599) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (558) Content-Type: application/mercurial-0.1\r\n
  write(21 from 21) -> (537) Content-Length: 417\r\n
  write(2 from 2) -> (535) \r\n
  write(417 from 417) -> (118) lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps unbundle=HG10GZ,HG10BZ,HG10UN httpheader=1024 httpmediatype=0.1rx,0.1tx,0.2tx compression=none
  readline(65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(-1) -> (41) x-hgarg-1: cmds=heads+%3Bknown+nodes%3D\r\n
  readline(-1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (82) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (59) Server: badhttpserver\r\n
  write(37 from 37) -> (22) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(22 from 41) -> (0) Content-Type: applicat
  write limit reached; closing socket
  write(36) -> HTTP/1.1 500 Internal Server Error\r\n

  $ rm -f error.log

Server sends an incomplete HTTP response body to batch request

  $ hg serve --config badserver.closeaftersendbytes=760 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

TODO client spews a stack due to uncaught ValueError in batch.results()
#if no-chg
  $ hg clone http://localhost:$HGPORT/ clone 2> /dev/null
  [1]
#else
  $ hg clone http://localhost:$HGPORT/ clone 2> /dev/null
  [255]
#endif

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (724) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (701) Server: badhttpserver\r\n
  write(37 from 37) -> (664) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (623) Content-Type: application/mercurial-0.1\r\n
  write(21 from 21) -> (602) Content-Length: 417\r\n
  write(2 from 2) -> (600) \r\n
  write(417 from 417) -> (183) lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps unbundle=HG10GZ,HG10BZ,HG10UN httpheader=1024 httpmediatype=0.1rx,0.1tx,0.2tx compression=none
  readline(65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(-1) -> (41) x-hgarg-1: cmds=heads+%3Bknown+nodes%3D\r\n
  readline(-1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (147) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (124) Server: badhttpserver\r\n
  write(37 from 37) -> (87) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (46) Content-Type: application/mercurial-0.1\r\n
  write(20 from 20) -> (26) Content-Length: 42\r\n
  write(2 from 2) -> (24) \r\n
  write(24 from 42) -> (0) 96ee1d7354c4ad7372047672
  write limit reached; closing socket

  $ rm -f error.log

Server sends incomplete headers for getbundle response

  $ hg serve --config badserver.closeaftersendbytes=907 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

TODO this output is terrible

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  abort: 'http://localhost:$HGPORT/' does not appear to be an hg repository:
  ---%<--- (application/mercuri)
  
  ---%<---
  !
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (871) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (848) Server: badhttpserver\r\n
  write(37 from 37) -> (811) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (770) Content-Type: application/mercurial-0.1\r\n
  write(21 from 21) -> (749) Content-Length: 417\r\n
  write(2 from 2) -> (747) \r\n
  write(417 from 417) -> (330) lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps unbundle=HG10GZ,HG10BZ,HG10UN httpheader=1024 httpmediatype=0.1rx,0.1tx,0.2tx compression=none
  readline(65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(-1) -> (41) x-hgarg-1: cmds=heads+%3Bknown+nodes%3D\r\n
  readline(-1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (294) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (271) Server: badhttpserver\r\n
  write(37 from 37) -> (234) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (193) Content-Type: application/mercurial-0.1\r\n
  write(20 from 20) -> (173) Content-Length: 42\r\n
  write(2 from 2) -> (171) \r\n
  write(42 from 42) -> (129) 96ee1d7354c4ad7372047672c36a1f561e3a6a4c\n;
  readline(65537) -> (30) GET /?cmd=getbundle HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(-1) -> (422) x-hgarg-1: bookmarks=1&bundlecaps=HG20%2Cbundle2%3DHG20%250Abookmarks%250Achangegroup%253D01%252C02%250Adigests%253Dmd5%252Csha1%252Csha512%250Aerror%253Dabort%252Cunsupportedcontent%252Cpushraced%252Cpushkey%250Ahgtagsfnodes%250Alistkeys%250Apushkey%250Aremote-changegroup%253Dhttp%252Chttps&cg=1&common=0000000000000000000000000000000000000000&heads=96ee1d7354c4ad7372047672c36a1f561e3a6a4c&listkeys=phases%2Cbookmarks\r\n
  readline(-1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (93) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (70) Server: badhttpserver\r\n
  write(37 from 37) -> (33) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(33 from 41) -> (0) Content-Type: application/mercuri
  write limit reached; closing socket
  write(36) -> HTTP/1.1 500 Internal Server Error\r\n

  $ rm -f error.log

Server sends empty HTTP body for getbundle

  $ hg serve --config badserver.closeaftersendbytes=945 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  abort: HTTP request error (incomplete response)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (909) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (886) Server: badhttpserver\r\n
  write(37 from 37) -> (849) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (808) Content-Type: application/mercurial-0.1\r\n
  write(21 from 21) -> (787) Content-Length: 417\r\n
  write(2 from 2) -> (785) \r\n
  write(417 from 417) -> (368) lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps unbundle=HG10GZ,HG10BZ,HG10UN httpheader=1024 httpmediatype=0.1rx,0.1tx,0.2tx compression=none
  readline(65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(-1) -> (41) x-hgarg-1: cmds=heads+%3Bknown+nodes%3D\r\n
  readline(-1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (332) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (309) Server: badhttpserver\r\n
  write(37 from 37) -> (272) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (231) Content-Type: application/mercurial-0.1\r\n
  write(20 from 20) -> (211) Content-Length: 42\r\n
  write(2 from 2) -> (209) \r\n
  write(42 from 42) -> (167) 96ee1d7354c4ad7372047672c36a1f561e3a6a4c\n;
  readline(65537) -> (30) GET /?cmd=getbundle HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(-1) -> (422) x-hgarg-1: bookmarks=1&bundlecaps=HG20%2Cbundle2%3DHG20%250Abookmarks%250Achangegroup%253D01%252C02%250Adigests%253Dmd5%252Csha1%252Csha512%250Aerror%253Dabort%252Cunsupportedcontent%252Cpushraced%252Cpushkey%250Ahgtagsfnodes%250Alistkeys%250Apushkey%250Aremote-changegroup%253Dhttp%252Chttps&cg=1&common=0000000000000000000000000000000000000000&heads=96ee1d7354c4ad7372047672c36a1f561e3a6a4c&listkeys=phases%2Cbookmarks\r\n
  readline(-1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (131) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (108) Server: badhttpserver\r\n
  write(37 from 37) -> (71) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (30) Content-Type: application/mercurial-0.2\r\n
  write(28 from 28) -> (2) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (0) \r\n
  write limit reached; closing socket
  write(36) -> HTTP/1.1 500 Internal Server Error\r\n

  $ rm -f error.log

Server sends partial compression string

  $ hg serve --config badserver.closeaftersendbytes=969 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  abort: HTTP request error (incomplete response)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ cat error.log
  readline(65537) -> (33) GET /?cmd=capabilities HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (933) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (910) Server: badhttpserver\r\n
  write(37 from 37) -> (873) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (832) Content-Type: application/mercurial-0.1\r\n
  write(21 from 21) -> (811) Content-Length: 417\r\n
  write(2 from 2) -> (809) \r\n
  write(417 from 417) -> (392) lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps unbundle=HG10GZ,HG10BZ,HG10UN httpheader=1024 httpmediatype=0.1rx,0.1tx,0.2tx compression=none
  readline(65537) -> (26) GET /?cmd=batch HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(-1) -> (41) x-hgarg-1: cmds=heads+%3Bknown+nodes%3D\r\n
  readline(-1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (356) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (333) Server: badhttpserver\r\n
  write(37 from 37) -> (296) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (255) Content-Type: application/mercurial-0.1\r\n
  write(20 from 20) -> (235) Content-Length: 42\r\n
  write(2 from 2) -> (233) \r\n
  write(42 from 42) -> (191) 96ee1d7354c4ad7372047672c36a1f561e3a6a4c\n;
  readline(65537) -> (30) GET /?cmd=getbundle HTTP/1.1\r\n
  readline(-1) -> (27) Accept-Encoding: identity\r\n
  readline(-1) -> (29) vary: X-HgArg-1,X-HgProto-1\r\n
  readline(-1) -> (422) x-hgarg-1: bookmarks=1&bundlecaps=HG20%2Cbundle2%3DHG20%250Abookmarks%250Achangegroup%253D01%252C02%250Adigests%253Dmd5%252Csha1%252Csha512%250Aerror%253Dabort%252Cunsupportedcontent%252Cpushraced%252Cpushkey%250Ahgtagsfnodes%250Alistkeys%250Apushkey%250Aremote-changegroup%253Dhttp%252Chttps&cg=1&common=0000000000000000000000000000000000000000&heads=96ee1d7354c4ad7372047672c36a1f561e3a6a4c&listkeys=phases%2Cbookmarks\r\n
  readline(-1) -> (48) x-hgproto-1: 0.1 0.2 comp=$USUAL_COMPRESSIONS$\r\n
  readline(-1) -> (35) accept: application/mercurial-0.1\r\n
  readline(-1) -> (2?) host: localhost:$HGPORT\r\n (glob)
  readline(-1) -> (49) user-agent: mercurial/proto-1.0 (Mercurial 4.2)\r\n
  readline(-1) -> (2) \r\n
  write(36 from 36) -> (155) HTTP/1.1 200 Script output follows\r\n
  write(23 from 23) -> (132) Server: badhttpserver\r\n
  write(37 from 37) -> (95) Date: Fri, 14 Apr 2017 00:00:00 GMT\r\n
  write(41 from 41) -> (54) Content-Type: application/mercurial-0.2\r\n
  write(28 from 28) -> (26) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (24) \r\n
  write(6 from 6) -> (18) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (9) 4\r\nnone\r\n
  write(9 from 9) -> (0) 4\r\nHG20\r\n
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Server sends partial bundle2 header magic

  $ hg serve --config badserver.closeaftersendbytes=966 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  abort: HTTP request error (incomplete response; expected 1 bytes got 3)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ tail -7 error.log
  write(28 from 28) -> (23) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (21) \r\n
  write(6 from 6) -> (15) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (6) 4\r\nnone\r\n
  write(6 from 9) -> (0) 4\r\nHG2
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Server sends incomplete bundle2 stream params length

  $ hg serve --config badserver.closeaftersendbytes=975 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  abort: HTTP request error (incomplete response; expected 1 bytes got 3)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ tail -8 error.log
  write(28 from 28) -> (32) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (30) \r\n
  write(6 from 6) -> (24) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (15) 4\r\nnone\r\n
  write(9 from 9) -> (6) 4\r\nHG20\r\n
  write(6 from 9) -> (0) 4\\r\\n\x00\x00\x00 (esc)
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Servers stops after bundle2 stream params header

  $ hg serve --config badserver.closeaftersendbytes=978 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  abort: HTTP request error (incomplete response)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ tail -8 error.log
  write(28 from 28) -> (35) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (33) \r\n
  write(6 from 6) -> (27) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (18) 4\r\nnone\r\n
  write(9 from 9) -> (9) 4\r\nHG20\r\n
  write(9 from 9) -> (0) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Server stops sending after bundle2 part header length

  $ hg serve --config badserver.closeaftersendbytes=987 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  abort: HTTP request error (incomplete response)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ tail -9 error.log
  write(28 from 28) -> (44) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (42) \r\n
  write(6 from 6) -> (36) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (27) 4\r\nnone\r\n
  write(9 from 9) -> (18) 4\r\nHG20\r\n
  write(9 from 9) -> (9) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (0) 4\\r\\n\x00\x00\x00)\\r\\n (esc)
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Server stops sending after bundle2 part header

  $ hg serve --config badserver.closeaftersendbytes=1034 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  adding changesets
  transaction abort!
  rollback completed
  abort: HTTP request error (incomplete response)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ tail -10 error.log
  write(28 from 28) -> (91) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (89) \r\n
  write(6 from 6) -> (83) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (74) 4\r\nnone\r\n
  write(9 from 9) -> (65) 4\r\nHG20\r\n
  write(9 from 9) -> (56) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (47) 4\\r\\n\x00\x00\x00)\\r\\n (esc)
  write(47 from 47) -> (0) 29\\r\\n\x0bCHANGEGROUP\x00\x00\x00\x00\x01\x01\x07\x02	\x01version02nbchanges1\\r\\n (esc)
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Server stops after bundle2 part payload chunk size

  $ hg serve --config badserver.closeaftersendbytes=1055 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  adding changesets
  transaction abort!
  rollback completed
  abort: HTTP request error (incomplete response; expected 459 bytes got 7)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ tail -11 error.log
  write(2 from 2) -> (110) \r\n
  write(6 from 6) -> (104) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (95) 4\r\nnone\r\n
  write(9 from 9) -> (86) 4\r\nHG20\r\n
  write(9 from 9) -> (77) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (68) 4\\r\\n\x00\x00\x00)\\r\\n (esc)
  write(47 from 47) -> (21) 29\\r\\n\x0bCHANGEGROUP\x00\x00\x00\x00\x01\x01\x07\x02	\x01version02nbchanges1\\r\\n (esc)
  write(9 from 9) -> (12) 4\\r\\n\x00\x00\x01\xd2\\r\\n (esc)
  write(12 from 473) -> (0) 1d2\\r\\n\x00\x00\x00\xb2\x96\xee\x1d (esc)
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Server stops sending in middle of bundle2 payload chunk

  $ hg serve --config badserver.closeaftersendbytes=1516 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  adding changesets
  transaction abort!
  rollback completed
  abort: HTTP request error (incomplete response)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ tail -12 error.log
  write(28 from 28) -> (573) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (571) \r\n
  write(6 from 6) -> (565) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (556) 4\r\nnone\r\n
  write(9 from 9) -> (547) 4\r\nHG20\r\n
  write(9 from 9) -> (538) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (529) 4\\r\\n\x00\x00\x00)\\r\\n (esc)
  write(47 from 47) -> (482) 29\\r\\n\x0bCHANGEGROUP\x00\x00\x00\x00\x01\x01\x07\x02	\x01version02nbchanges1\\r\\n (esc)
  write(9 from 9) -> (473) 4\\r\\n\x00\x00\x01\xd2\\r\\n (esc)
  write(473 from 473) -> (0) 1d2\\r\\n\x00\x00\x00\xb2\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00>6a3df4de388f3c4f8e28f4f9a814299a3cbb5f50\\ntest\\n0 0\\nfoo\\n\\ninitial\x00\x00\x00\x00\x00\x00\x00\xa1j=\xf4\xde8\x8f<O\x8e(\xf4\xf9\xa8\x14)\x9a<\xbb_P\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00-foo\x00b80de5d138758541c5f05265ad144ab9fa86d1db\\n\x00\x00\x00\x00\x00\x00\x00\x07foo\x00\x00\x00h\xb8\\r\xe5\xd18u\x85A\xc5\xf0Re\xad\x14J\xb9\xfa\x86\xd1\xdb\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\\r\\n (esc)
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Server stops sending after 0 length payload chunk size

  $ hg serve --config badserver.closeaftersendbytes=1547 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  transaction abort!
  rollback completed
  abort: HTTP request error (incomplete response; expected 23 bytes got 9)
  (this may be an intermittent network failure; if the error persists, consider contacting the network or server operator)
  [255]

  $ killdaemons.py $DAEMON_PIDS

  $ tail -13 error.log
  write(6 from 6) -> (596) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (587) 4\r\nnone\r\n
  write(9 from 9) -> (578) 4\r\nHG20\r\n
  write(9 from 9) -> (569) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (560) 4\\r\\n\x00\x00\x00)\\r\\n (esc)
  write(47 from 47) -> (513) 29\\r\\n\x0bCHANGEGROUP\x00\x00\x00\x00\x01\x01\x07\x02	\x01version02nbchanges1\\r\\n (esc)
  write(9 from 9) -> (504) 4\\r\\n\x00\x00\x01\xd2\\r\\n (esc)
  write(473 from 473) -> (31) 1d2\\r\\n\x00\x00\x00\xb2\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00>6a3df4de388f3c4f8e28f4f9a814299a3cbb5f50\\ntest\\n0 0\\nfoo\\n\\ninitial\x00\x00\x00\x00\x00\x00\x00\xa1j=\xf4\xde8\x8f<O\x8e(\xf4\xf9\xa8\x14)\x9a<\xbb_P\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00-foo\x00b80de5d138758541c5f05265ad144ab9fa86d1db\\n\x00\x00\x00\x00\x00\x00\x00\x07foo\x00\x00\x00h\xb8\\r\xe5\xd18u\x85A\xc5\xf0Re\xad\x14J\xb9\xfa\x86\xd1\xdb\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (22) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (13) 4\\r\\n\x00\x00\x00 \\r\\n (esc)
  write(13 from 38) -> (0) 20\\r\\n\x08LISTKEYS (esc)
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log

Server stops sending after 0 part bundle part header (indicating end of bundle2 payload)
This is before the 0 size chunked transfer part that signals end of HTTP response.

  $ hg serve --config badserver.closeaftersendbytes=1722 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 96ee1d7354c4
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ killdaemons.py $DAEMON_PIDS

  $ tail -22 error.log
  write(28 from 28) -> (779) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (777) \r\n
  write(6 from 6) -> (771) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (762) 4\r\nnone\r\n
  write(9 from 9) -> (753) 4\r\nHG20\r\n
  write(9 from 9) -> (744) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (735) 4\\r\\n\x00\x00\x00)\\r\\n (esc)
  write(47 from 47) -> (688) 29\\r\\n\x0bCHANGEGROUP\x00\x00\x00\x00\x01\x01\x07\x02	\x01version02nbchanges1\\r\\n (esc)
  write(9 from 9) -> (679) 4\\r\\n\x00\x00\x01\xd2\\r\\n (esc)
  write(473 from 473) -> (206) 1d2\\r\\n\x00\x00\x00\xb2\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00>6a3df4de388f3c4f8e28f4f9a814299a3cbb5f50\\ntest\\n0 0\\nfoo\\n\\ninitial\x00\x00\x00\x00\x00\x00\x00\xa1j=\xf4\xde8\x8f<O\x8e(\xf4\xf9\xa8\x14)\x9a<\xbb_P\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00-foo\x00b80de5d138758541c5f05265ad144ab9fa86d1db\\n\x00\x00\x00\x00\x00\x00\x00\x07foo\x00\x00\x00h\xb8\\r\xe5\xd18u\x85A\xc5\xf0Re\xad\x14J\xb9\xfa\x86\xd1\xdb\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (197) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (188) 4\\r\\n\x00\x00\x00 \\r\\n (esc)
  write(38 from 38) -> (150) 20\\r\\n\x08LISTKEYS\x00\x00\x00\x01\x01\x00	\x06namespacephases\\r\\n (esc)
  write(9 from 9) -> (141) 4\\r\\n\x00\x00\x00:\\r\\n (esc)
  write(64 from 64) -> (77) 3a\r\n96ee1d7354c4ad7372047672c36a1f561e3a6a4c	1\npublishing	True\r\n
  write(9 from 9) -> (68) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (59) 4\\r\\n\x00\x00\x00#\\r\\n (esc)
  write(41 from 41) -> (18) 23\\r\\n\x08LISTKEYS\x00\x00\x00\x02\x01\x00		namespacebookmarks\\r\\n (esc)
  write(9 from 9) -> (9) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (0) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log
  $ rm -rf clone

Server sends a size 0 chunked-transfer size without terminating \r\n

  $ hg serve --config badserver.closeaftersendbytes=1725 -p $HGPORT -d --pid-file=hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

  $ hg clone http://localhost:$HGPORT/ clone
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 96ee1d7354c4
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ killdaemons.py $DAEMON_PIDS

  $ tail -23 error.log
  write(28 from 28) -> (782) Transfer-Encoding: chunked\r\n
  write(2 from 2) -> (780) \r\n
  write(6 from 6) -> (774) 1\\r\\n\x04\\r\\n (esc)
  write(9 from 9) -> (765) 4\r\nnone\r\n
  write(9 from 9) -> (756) 4\r\nHG20\r\n
  write(9 from 9) -> (747) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (738) 4\\r\\n\x00\x00\x00)\\r\\n (esc)
  write(47 from 47) -> (691) 29\\r\\n\x0bCHANGEGROUP\x00\x00\x00\x00\x01\x01\x07\x02	\x01version02nbchanges1\\r\\n (esc)
  write(9 from 9) -> (682) 4\\r\\n\x00\x00\x01\xd2\\r\\n (esc)
  write(473 from 473) -> (209) 1d2\\r\\n\x00\x00\x00\xb2\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00>6a3df4de388f3c4f8e28f4f9a814299a3cbb5f50\\ntest\\n0 0\\nfoo\\n\\ninitial\x00\x00\x00\x00\x00\x00\x00\xa1j=\xf4\xde8\x8f<O\x8e(\xf4\xf9\xa8\x14)\x9a<\xbb_P\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00-foo\x00b80de5d138758541c5f05265ad144ab9fa86d1db\\n\x00\x00\x00\x00\x00\x00\x00\x07foo\x00\x00\x00h\xb8\\r\xe5\xd18u\x85A\xc5\xf0Re\xad\x14J\xb9\xfa\x86\xd1\xdb\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x96\xee\x1dsT\xc4\xadsr\x04vr\xc3j\x1fV\x1e:jL\x00\x00\x00\x00\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (200) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (191) 4\\r\\n\x00\x00\x00 \\r\\n (esc)
  write(38 from 38) -> (153) 20\\r\\n\x08LISTKEYS\x00\x00\x00\x01\x01\x00	\x06namespacephases\\r\\n (esc)
  write(9 from 9) -> (144) 4\\r\\n\x00\x00\x00:\\r\\n (esc)
  write(64 from 64) -> (80) 3a\r\n96ee1d7354c4ad7372047672c36a1f561e3a6a4c	1\npublishing	True\r\n
  write(9 from 9) -> (71) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (62) 4\\r\\n\x00\x00\x00#\\r\\n (esc)
  write(41 from 41) -> (21) 23\\r\\n\x08LISTKEYS\x00\x00\x00\x02\x01\x00		namespacebookmarks\\r\\n (esc)
  write(9 from 9) -> (12) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(9 from 9) -> (3) 4\\r\\n\x00\x00\x00\x00\\r\\n (esc)
  write(3 from 5) -> (0) 0\r\n
  write limit reached; closing socket
  write(27) -> 15\r\nInternal Server Error\r\n

  $ rm -f error.log
  $ rm -rf clone