tests/test-impexp-branch.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

  $ echo '[extensions]' >> $HGRCPATH
  $ echo 'strip =' >> $HGRCPATH

  $ cat >findbranch.py <<EOF
  > from __future__ import absolute_import
  > import re
  > import sys
  > 
  > head_re = re.compile(r'^#(?:(?:\\s+([A-Za-z][A-Za-z0-9_]*)(?:\\s.*)?)|(?:\\s*))$')
  > 
  > for line in sys.stdin:
  >     hmatch = head_re.match(line)
  >     if not hmatch:
  >         sys.exit(1)
  >     if hmatch.group(1) == 'Branch':
  >         sys.exit(0)
  > sys.exit(1)
  > EOF

  $ hg init a
  $ cd a
  $ echo "Rev 1" >rev
  $ hg add rev
  $ hg commit -m "No branch."
  $ hg branch abranch
  marked working directory as branch abranch
  (branches are permanent and global, did you want a bookmark?)
  $ echo "Rev  2" >rev
  $ hg commit -m "With branch."

  $ hg export 0 > ../r0.patch
  $ hg export 1 > ../r1.patch
  $ cd ..

  $ if "$PYTHON" findbranch.py < r0.patch; then
  >     echo "Export of default branch revision has Branch header" 1>&2
  >     exit 1
  > fi

  $ if "$PYTHON" findbranch.py < r1.patch; then
  >     :  # Do nothing
  > else
  >     echo "Export of branch revision is missing Branch header" 1>&2
  >     exit 1
  > fi

Make sure import still works with branch information in patches.

  $ hg init b
  $ cd b
  $ hg import ../r0.patch
  applying ../r0.patch
  $ hg import ../r1.patch
  applying ../r1.patch
  $ cd ..

  $ hg init c
  $ cd c
  $ hg import --exact --no-commit ../r0.patch
  applying ../r0.patch
  warning: can't check exact import with --no-commit
  $ hg st
  A rev
  $ hg revert -a
  forgetting rev
  $ rm rev
  $ hg import --exact ../r0.patch
  applying ../r0.patch
  $ hg import --exact ../r1.patch
  applying ../r1.patch

Test --exact and patch header separators (issue3356)

  $ hg strip --no-backup .
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  >>> import re
  >>> p = open('../r1.patch', 'rb').read()
  >>> p = re.sub(br'Parent\s+', b'Parent ', p)
  >>> open('../r1-ws.patch', 'wb').write(p) and None
  $ hg import --exact ../r1-ws.patch
  applying ../r1-ws.patch

  $ cd ..