view tests/test-rebase-empty-successor.t @ 47682:78f7f0d490ee

dirstate-v2: Move fixed-size tree metadata into the docket file

Before this changeset, the dirstate-v2 data file contained not only nodes
and paths that may be reused when appending to an existing file,
but also some fixed-size metadata that applies to the entire tree
and was added at the end of the data file for every append.

This moves that metadata into the docket file, so that repeated "append"
operations without meaningful changes don’t actually need to grow any file.

Differential Revision: https://phab.mercurial-scm.org/D11098

  $ cat << EOF >> $HGRCPATH
  > [extensions]
  > rebase=
  > [alias]
  > tglog = log -G -T "{rev} '{desc}'\n"
  > EOF

  $ hg init

  $ echo a > a; hg add a; hg ci -m a
  $ echo b > b; hg add b; hg ci -m b1
  $ hg up 0 -q
  $ echo b > b; hg add b; hg ci -m b2 -q

  $ hg tglog
  @  2 'b2'
  |
  | o  1 'b1'
  |/
  o  0 'a'
  

With rewrite.empty-successor=skip, b2 is skipped because it would become empty.

  $ hg rebase -s 2 -d 1 --config rewrite.empty-successor=skip --dry-run
  starting dry-run rebase; repository will not be changed
  rebasing 2:6e2aad5e0f3c tip "b2"
  note: not rebasing 2:6e2aad5e0f3c tip "b2", its destination already has all its changes
  dry-run rebase completed successfully; run without -n/--dry-run to perform this rebase

With rewrite.empty-successor=keep, b2 will be recreated although it became empty.

  $ hg rebase -s 2 -d 1 --config rewrite.empty-successor=keep
  rebasing 2:6e2aad5e0f3c tip "b2"
  note: created empty successor for 2:6e2aad5e0f3c tip "b2", its destination already has all its changes
  saved backup bundle to $TESTTMP/.hg/strip-backup/6e2aad5e0f3c-7d7c8801-rebase.hg

  $ hg tglog
  @  2 'b2'
  |
  o  1 'b1'
  |
  o  0 'a'