tests/remotefilelog-getflogheads.py

merge: introduce a clean_update() for that use-case

I find it hard to understand what value to pass for all the arguments
to `merge.update()`. I would like to introduce functions that are more
specific to each use-case. We already have `graft()`. This patch
introduces a `clean_update()` and uses it in some places to show that
it works.

Differential Revision: https://phab.mercurial-scm.org/D7902

from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import (
    hg,
    registrar,
)

cmdtable = {}
command = registrar.command(cmdtable)


@command(b'getflogheads', [], b'path')
def getflogheads(ui, repo, path):
    """
    Extension printing a remotefilelog's heads

    Used for testing purpose
    """

    dest = repo.ui.expandpath(b'default')
    peer = hg.peer(repo, {}, dest)

    flogheads = peer.x_rfl_getflogheads(path)

    if flogheads:
        for head in flogheads:
            ui.write(head + b'\n')
    else:
        ui.write(_(b'EMPTY\n'))