view tests/test-absorb-rename.t @ 45121:b6269741ed42

config: add option to control creation of empty successors during rewrite

The default for many history-rewriting commands (e.g. rebase and absorb) is
that changesets which would become empty are not created in the target branch.
This makes sense if the source branch consists of small fix-up changes. For
more advanced workflows that make heavy use of history-editing to create
curated patch series, dropping empty changesets is not as important or even
undesirable.

Some users want to keep the meta-history, e.g. to make finding comments in a
code review tool easier or to avoid that divergent bookmarks are created. For
that, obsmarkers from the (to-be) empty changeset to the changeset(s) that
already made the changes should be added. If a to-be empty changeset is pruned
without a successor, adding the obsmarkers is hard because the changeset has to
be found within the hidden part of the history.

If rebasing in TortoiseHg, it’s easy to miss the fact that the to-be empty
changeset was pruned. An empty changeset will function as a reminder that
obsmarkers should be added.

Martin von Zweigbergk mentioned another advantage. Stripping the successor will
de-obsolete the predecessor. If no (empty) successor is created, this won’t be
possible.

In the future, we may want to consider other behaviors, like e.g. creating the
empty successor, but pruning it right away. Therefore this configuration
accepts 'skip' and 'keep' instead of being a boolean configuration.

  $ cat >> $HGRCPATH << EOF
  > [diff]
  > git=1
  > [extensions]
  > absorb=
  > EOF

  $ sedi() { # workaround check-code
  > pattern="$1"
  > shift
  > for i in "$@"; do
  >     sed "$pattern" "$i" > "$i".tmp
  >     mv "$i".tmp "$i"
  > done
  > }

rename a to b, then b to a

  $ hg init repo1
  $ cd repo1

  $ echo 1 > a
  $ hg ci -A a -m 1
  $ hg mv a b
  $ echo 2 >> b
  $ hg ci -m 2
  $ hg mv b a
  $ echo 3 >> a
  $ hg ci -m 3

  $ hg annotate -ncf a
  0 eff892de26ec a: 1
  1 bf56e1f4f857 b: 2
  2 0b888b00216c a: 3

  $ sedi 's/$/a/' a
  $ hg absorb -apq
  showing changes for a
          @@ -0,3 +0,3 @@
  eff892d -1
  bf56e1f -2
  0b888b0 -3
  eff892d +1a
  bf56e1f +2a
  0b888b0 +3a
  
  3 changesets affected
  0b888b0 3
  bf56e1f 2
  eff892d 1

  $ hg status

  $ hg annotate -ncf a
  0 5d1c5620e6f2 a: 1a
  1 9a14ffe67ae9 b: 2a
  2 9191d121a268 a: 3a

when the first changeset is public

  $ hg phase --public -r 0

  $ sedi 's/a/A/' a

  $ hg absorb -apq
  showing changes for a
          @@ -0,3 +0,3 @@
          -1a
  9a14ffe -2a
  9191d12 -3a
          +1A
  9a14ffe +2A
  9191d12 +3A
  
  2 changesets affected
  9191d12 3
  9a14ffe 2

  $ hg diff
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,3 @@
  -1a
  +1A
   2A
   3A

copy a to b

  $ cd ..
  $ hg init repo2
  $ cd repo2

  $ echo 1 > a
  $ hg ci -A a -m 1
  $ hg cp a b
  $ echo 2 >> b
  $ hg ci -m 2

  $ hg log -T '{rev}:{node|short} {desc}\n'
  1:17b72129ab68 2
  0:eff892de26ec 1

  $ sedi 's/$/a/' a
  $ sedi 's/$/b/' b

  $ hg absorb -apq
  showing changes for a
          @@ -0,1 +0,1 @@
  eff892d -1
  eff892d +1a
  showing changes for b
          @@ -0,2 +0,2 @@
          -1
  17b7212 -2
          +1b
  17b7212 +2b
  
  2 changesets affected
  17b7212 2
  eff892d 1

  $ hg diff
  diff --git a/b b/b
  --- a/b
  +++ b/b
  @@ -1,2 +1,2 @@
  -1
  +1b
   2b

copy b to a

  $ cd ..
  $ hg init repo3
  $ cd repo3

  $ echo 1 > b
  $ hg ci -A b -m 1
  $ hg cp b a
  $ echo 2 >> a
  $ hg ci -m 2

  $ hg log -T '{rev}:{node|short} {desc}\n'
  1:e62c256d8b24 2
  0:55105f940d5c 1

  $ sedi 's/$/a/' a
  $ sedi 's/$/a/' b

  $ hg absorb -apq
  showing changes for a
          @@ -0,2 +0,2 @@
          -1
  e62c256 -2
          +1a
  e62c256 +2a
  showing changes for b
          @@ -0,1 +0,1 @@
  55105f9 -1
  55105f9 +1a
  
  2 changesets affected
  e62c256 2
  55105f9 1

  $ hg diff
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,2 +1,2 @@
  -1
  +1a
   2a

"move" b to both a and c, follow a - sorted alphabetically

  $ cd ..
  $ hg init repo4
  $ cd repo4

  $ echo 1 > b
  $ hg ci -A b -m 1
  $ hg cp b a
  $ hg cp b c
  $ hg rm b
  $ echo 2 >> a
  $ echo 3 >> c
  $ hg commit -m cp

  $ hg log -T '{rev}:{node|short} {desc}\n'
  1:366daad8e679 cp
  0:55105f940d5c 1

  $ sedi 's/$/a/' a
  $ sedi 's/$/c/' c

  $ hg absorb -apq
  showing changes for a
          @@ -0,2 +0,2 @@
  55105f9 -1
  366daad -2
  55105f9 +1a
  366daad +2a
  showing changes for c
          @@ -0,2 +0,2 @@
          -1
  366daad -3
          +1c
  366daad +3c
  
  2 changesets affected
  366daad cp
  55105f9 1

  $ hg log -G -p -T '{rev}:{node|short} {desc}\n'
  @  1:70606019f91b cp
  |  diff --git a/b b/a
  |  rename from b
  |  rename to a
  |  --- a/b
  |  +++ b/a
  |  @@ -1,1 +1,2 @@
  |   1a
  |  +2a
  |  diff --git a/b b/c
  |  copy from b
  |  copy to c
  |  --- a/b
  |  +++ b/c
  |  @@ -1,1 +1,2 @@
  |  -1a
  |  +1
  |  +3c
  |
  o  0:bfb67c3539c1 1
     diff --git a/b b/b
     new file mode 100644
     --- /dev/null
     +++ b/b
     @@ -0,0 +1,1 @@
     +1a
  
run absorb again would apply the change to c

  $ hg absorb -apq
  showing changes for c
          @@ -0,1 +0,1 @@
  7060601 -1
  7060601 +1c
  
  1 changesets affected
  7060601 cp

  $ hg log -G -p -T '{rev}:{node|short} {desc}\n'
  @  1:8bd536cce368 cp
  |  diff --git a/b b/a
  |  rename from b
  |  rename to a
  |  --- a/b
  |  +++ b/a
  |  @@ -1,1 +1,2 @@
  |   1a
  |  +2a
  |  diff --git a/b b/c
  |  copy from b
  |  copy to c
  |  --- a/b
  |  +++ b/c
  |  @@ -1,1 +1,2 @@
  |  -1a
  |  +1c
  |  +3c
  |
  o  0:bfb67c3539c1 1
     diff --git a/b b/b
     new file mode 100644
     --- /dev/null
     +++ b/b
     @@ -0,0 +1,1 @@
     +1a
  
"move" b to a, c and d, follow d if a gets renamed to e, and c is deleted

  $ cd ..
  $ hg init repo5
  $ cd repo5

  $ echo 1 > b
  $ hg ci -A b -m 1
  $ hg cp b a
  $ hg cp b c
  $ hg cp b d
  $ hg rm b
  $ echo 2 >> a
  $ echo 3 >> c
  $ echo 4 >> d
  $ hg commit -m cp
  $ hg mv a e
  $ hg rm c
  $ hg commit -m mv

  $ hg log -T '{rev}:{node|short} {desc}\n'
  2:49911557c471 mv
  1:7bc3d43ede83 cp
  0:55105f940d5c 1

  $ sedi 's/$/e/' e
  $ sedi 's/$/d/' d

  $ hg absorb -apq
  showing changes for d
          @@ -0,2 +0,2 @@
  55105f9 -1
  7bc3d43 -4
  55105f9 +1d
  7bc3d43 +4d
  showing changes for e
          @@ -0,2 +0,2 @@
          -1
  7bc3d43 -2
          +1e
  7bc3d43 +2e
  
  2 changesets affected
  7bc3d43 cp
  55105f9 1

  $ hg diff
  diff --git a/e b/e
  --- a/e
  +++ b/e
  @@ -1,2 +1,2 @@
  -1
  +1e
   2e

  $ hg log -G -p -T '{rev}:{node|short} {desc}\n'
  @  2:34be9b0c786e mv
  |  diff --git a/c b/c
  |  deleted file mode 100644
  |  --- a/c
  |  +++ /dev/null
  |  @@ -1,2 +0,0 @@
  |  -1
  |  -3
  |  diff --git a/a b/e
  |  rename from a
  |  rename to e
  |
  o  1:13e56db5948d cp
  |  diff --git a/b b/a
  |  rename from b
  |  rename to a
  |  --- a/b
  |  +++ b/a
  |  @@ -1,1 +1,2 @@
  |  -1d
  |  +1
  |  +2e
  |  diff --git a/b b/c
  |  copy from b
  |  copy to c
  |  --- a/b
  |  +++ b/c
  |  @@ -1,1 +1,2 @@
  |  -1d
  |  +1
  |  +3
  |  diff --git a/b b/d
  |  copy from b
  |  copy to d
  |  --- a/b
  |  +++ b/d
  |  @@ -1,1 +1,2 @@
  |   1d
  |  +4d
  |
  o  0:0037613a5dc6 1
     diff --git a/b b/b
     new file mode 100644
     --- /dev/null
     +++ b/b
     @@ -0,0 +1,1 @@
     +1d