strip: calculate list of extra nodes to save and pass it to changegroupsubset
When we remove revision N from the repository, all revisions >= N are
affected: either it's a descendant from N and will also be removed, or
it's not a descendant of N and will be renumbered.
As a consequence, we have to (at least temporarily) remove all filelog
and manifest revisions that have a linkrev >= N, readding some of them
later.
Unfortunately, it's possible to have a revlog with two revisions
r1 and r2 such that r1 < r2, but linkrev(r1) > linkrev(r2). If we try
to strip revision linkrev(r1) from the repository, we'll also lose
revision r2 when we truncate this revlog.
We already use changegroupsubset to create a temporary changegroup
containing the revisions that have to be restored, but that function is
unable to detect that we also wanted to save the r2 in the case above.
So we manually calculate these extra nodes and pass it to changegroupsubset.
This should fix
issue764.
changegroupsubset: accept list of per-revlog nodes to include
This will allow strip to include in the temporary changegroup some extra
file/manifest revisions that should be restored after the truncations.
This code doesn't allow specification of changelog nodes since I won't
need that right now, the code wouldn't be tested and it's probably
possible to do something similar enough by using the bases/heads
arguments.