When we specify a revision or a revset we just get the last element from the
list. For revsets this can lead to unintended effects where you specify a
revset like only() but instead histedit selects the highest revision in the
set as root. Therefore we should always use the lowest revision number as
root.
Mercurial earlier than 2.7 allows users to do anything other than
starting new histedit, even though current histedit is not finished or
aborted yet. So, unfinished (and maybe inconsistent now) histedit
states may be left and forgotten in repositories.
Before this patch, histedit extension shows the message below, when it
detects such inconsistent state:
abort: REV is not an ancestor of working directory
(update to REV or descendant and run "hg histedit --continue" again)
But this message is incorrect, unless old Mercurial is re-installed,
because Mercurial 2.7 or later disallows users to update the working
directory to another revision.
This patch changes the hint message to suggest "hg histedit --abort".
Now that we explicitly detect duplicated changesets, we can explicitly
detect missing ones. We cover the same cases as before, some others
and we offer a better error message in all cases.
Before this change one would issue rules with duplicated entries. For
this to happen some other changeset had to be missing to maintain the
rules length.
There is some clue that the previous code intended to handle that but it was
actually not the case.
As a result action could apply to the empty string '' changeset,
leading to the use the current working directory parent in some
operations.
