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
#require reporevlogstore
A repo with unknown revlogv2 requirement string cannot be opened
$ hg init invalidreq
$ cd invalidreq
$ echo exp-revlogv2.unknown >> .hg/requires
$ hg log
abort: repository requires features unknown to this Mercurial: exp-revlogv2.unknown!
(see https://mercurial-scm.org/wiki/MissingRequirement for more information)
[255]
$ cd ..
Can create and open repo with revlog v2 requirement
$ cat >> $HGRCPATH << EOF
> [experimental]
> revlogv2 = enable-unstable-format-and-corrupt-my-data
> EOF
$ hg init empty-repo
$ cd empty-repo
$ cat .hg/requires
dotencode
exp-revlogv2.1
fncache
sparserevlog
store
$ hg log
Unknown flags to revlog are rejected
>>> with open('.hg/store/00changelog.i', 'wb') as fh:
... fh.write(b'\xff\x00\xde\xad') and None
$ hg log
abort: unknown flags (0xff00) in version 57005 revlog 00changelog.i!
[255]
$ cd ..
Writing a simple revlog v2 works
$ hg init simple
$ cd simple
$ touch foo
$ hg -q commit -A -m initial
$ hg log
changeset: 0:96ee1d7354c4
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: initial
Header written as expected
$ f --hexdump --bytes 4 .hg/store/00changelog.i
.hg/store/00changelog.i:
0000: 00 01 de ad |....|
$ f --hexdump --bytes 4 .hg/store/data/foo.i
.hg/store/data/foo.i:
0000: 00 01 de ad |....|