tests/test-remotefilelog-strip.t

emitrevision: if we need to compute a delta on the fly, try p1 or p2 first

Falling back to `prev` does not yield any real value on modern storage and
result in pathological changes to be created on the other side. Doing a delta
against a parent will likely be smaller (helping the network) and will be safer
to apply on the client (helping future pulls by Triggering intermediate
snapshop where they will be needed by later deltas).

#require no-windows

  $ . "$TESTDIR/remotefilelog-library.sh"

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > server=True
  > EOF
  $ echo x > x
  $ hg commit -qAm x

  $ cd ..

  $ hgcloneshallow ssh://user@dummy/master shallow -q
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
  $ cd shallow

  $ cat >> $TESTTMP/get_file_linknode.py <<EOF
  > from mercurial import node, registrar, scmutil
  > cmdtable = {}
  > command = registrar.command(cmdtable)
  > @command(b'debug-file-linknode', [(b'r', b'rev', b'.', b'rev')], b'hg debug-file-linknode FILE')
  > def debug_file_linknode(ui, repo, file, **opts):
  >   rflctx = scmutil.revsingle(repo.unfiltered(), opts['rev']).filectx(file)
  >   ui.status(b'%s\n' % node.hex(rflctx.ancestormap()[rflctx._filenode][2]))
  > EOF

  $ cat >> .hg/hgrc <<EOF
  > [ui]
  > interactive=1
  > [extensions]
  > strip=
  > get_file_linknode=$TESTTMP/get_file_linknode.py
  > [experimental]
  > evolution=createmarkers,allowunstable
  > EOF
  $ echo a > a
  $ hg commit -qAm msg1
  $ hg commit --amend 're:^$' -m msg2
  $ hg commit --amend 're:^$' -m msg3
  $ hg --hidden log -G -T '{rev} {node|short}'
  @  3 df91f74b871e
  |
  | x  2 70494d7ec5ef
  |/
  | x  1 1e423846dde0
  |/
  o  0 b292c1e3311f
  
  $ hg debug-file-linknode -r 70494d a
  df91f74b871e064c89afa1fe9e2f66afa2c125df
  $ hg --hidden strip -r 1 3
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/df91f74b871e-c94d67be-backup.hg

  $ hg --hidden log -G -T '{rev} {node|short}'
  o  1 70494d7ec5ef
  |
  @  0 b292c1e3311f
  
Demonstrate that the linknode points to a commit that is actually in the repo
after the strip operation. Otherwise remotefilelog has to search every commit in
the repository looking for a valid linkrev every time it's queried, such as
during push.
  $ hg debug-file-linknode -r 70494d a
  70494d7ec5ef6cd3cd6939a9fd2812f9956bf553