tests/test-hooklib-changeset_obsoleted.t

test: add test-transaction-rollback-on-sigpipe.t demonstrating py3 regression

When an hg push is interrupted with C-c, the remote [hg serve] command
receives SIGPIPE.

If a pretxnchangegroup hook fails, the remote hg then tries to
rollback the transaction. It begins by printing "transaction
abort!\n". This returns EPIPE, but ui.py ignores that error.

In python3 (but not python2), this "transaction abort!\n" message
stays in a buffer, so future flushes of stderr will try to print the
message again, and so those flushes will also hit EPIPE.

This test demonstrates such a case where this EPIPE causes the
transaction rollback to fail, leaving behind an abandoned transaction.

Differential Revision: https://phab.mercurial-scm.org/D9151

  $ cat <<EOF >> $HGRCPATH
  > [experimental]
  > evolution = true
  > 
  > [extensions]
  > notify =
  > hooklib =
  > 
  > [phases]
  > publish = False
  > 
  > [notify]
  > sources = pull
  > diffstat = False
  > messageidseed = example
  > domain = example.com
  > 
  > [reposubs]
  > * = baz
  > EOF
  $ hg init a
  $ hg --cwd a debugbuilddag +2
  $ hg init b
  $ cat <<EOF >> b/.hg/hgrc
  > [hooks]
  > incoming.notify = python:hgext.notify.hook
  > txnclose.changeset_obsoleted = python:hgext.hooklib.changeset_obsoleted.hook
  > EOF
  $ hg --cwd b pull ../a | "$PYTHON" $TESTDIR/unwrap-message-id.py
  pulling from ../a
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 0 changes to 0 files
  new changesets 1ea73414a91b:66f7d451a68b (2 drafts)
  MIME-Version: 1.0
  Content-Type: text/plain; charset="us-ascii"
  Content-Transfer-Encoding: 7bit
  Date: * (glob)
  Subject: changeset in * (glob)
  From: [e-mail]
  X-Hg-Notification: changeset 1ea73414a91b
  Message-Id: <hg.[e-mail]>
  To: [e-mail]
  
  changeset 1ea73414a91b in $TESTTMP/b
  details: $TESTTMP/b?cmd=changeset;node=1ea73414a91b
  description:
  	r0
  MIME-Version: 1.0
  Content-Type: text/plain; charset="us-ascii"
  Content-Transfer-Encoding: 7bit
  Date: * (glob)
  Subject: changeset in * (glob)
  From: [e-mail]
  X-Hg-Notification: changeset 66f7d451a68b
  Message-Id: <hg.[e-mail]>
  To: [e-mail]
  
  changeset 66f7d451a68b in $TESTTMP/b
  details: $TESTTMP/b?cmd=changeset;node=66f7d451a68b
  description:
  	r1
  (run 'hg update' to get a working copy)
  $ hg --cwd a debugobsolete 1ea73414a91b0920940797d8fc6a11e447f8ea1e
  1 new obsolescence markers
  obsoleted 1 changesets
  1 new orphan changesets
  $ hg --cwd a push ../b --hidden | "$PYTHON" $TESTDIR/unwrap-message-id.py
  1 new orphan changesets
  pushing to ../b
  searching for changes
  no changes found
  1 new obsolescence markers
  obsoleted 1 changesets
  Subject: changeset abandoned
  In-reply-to: <hg.[e-mail]>
  Message-Id: <hg.[e-mail]>
  Date: * (glob)
  From: [e-mail]
  To: [e-mail]
  
  This changeset has been abandoned.

Check that known changesets with known successors do not result in a mail.

  $ hg init c
  $ hg init d
  $ cat <<EOF >> d/.hg/hgrc
  > [hooks]
  > incoming.notify = python:hgext.notify.hook
  > txnclose.changeset_obsoleted = python:hgext.hooklib.changeset_obsoleted.hook
  > EOF
  $ hg --cwd c debugbuilddag '.:parent.*parent'
  $ hg --cwd c push ../d -r 1
  pushing to ../d
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 0 changes to 0 files
  $ hg --cwd c debugobsolete $(hg --cwd c log -T '{node}' -r 1) $(hg --cwd c log -T '{node}' -r 2)
  1 new obsolescence markers
  obsoleted 1 changesets
  $ hg --cwd c push ../d | "$PYTHON" $TESTDIR/unwrap-message-id.py
  pushing to ../d
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files (+1 heads)
  1 new obsolescence markers
  obsoleted 1 changesets