$ 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 ..