view tests/test-evolve-abort-contentdiv.t @ 3846:f9dad99a90d5

evolve: create a new commit instead of amending one of the divergents

This patch changes the behavior of evolve command while resolving
content-divergence to create a new commit instead of amending one of the
divergent ones.

In past, I have made this change, backed out this change and now today again I
am doing this change, so let's dive in some history.

Using cmdrewrite.amend() was never a good option as that requires hack to delete
the evolvestate and also gives us less control over things. We can't make the
commit on top of different parents as that of content-divergent ones. Due to all
these, I first made this change to create a new commit instead of amending one.

But, after few days, there was flakiness observed in the tests and turned out
that we need to do some dirstate dance as repo.dirstate.setparents() does not
always fix the dirstate. That flakiness was a blocker for progress at that time
and we decided to switch to amend back so that we can have things working with
some hacks and we can later fix the implementation part.

Now, yesterday while tackling resolving content-divergence of a stack which is
as follows:

C1 C2
 | |
B1 B2
 | |
A1 A2
 \/
base

where, A1-A2, B1-B2, C1-C2 are content-divergent with each other. Now we can
resolve A1-A2 very well because they have the same parent and let's say that
resolution leads to A3.
Now, we want to resolve B1-B2 and make the new resolution commit on top of A3 so
that we can end up something like:

C3
 |
B3
 |
A3
 |
base

however, amending one of the divergent changesets, it's not possible to create a
commit on a different parent like A3 here without some relocation. We should
prevent relocation as that may leads to some conflicts and should change the
parent before committing.

So, looking ahead, we can't move with using amend as still using that we will
need some relocation hacks making code ugly and prone to bad behaviors, bugs.
Let's change back to creating a new commit so that we can move forward in a good
way.

About repo.dirstate.setparents() not setting the dirstate, I have researched
yesterday night about how we can do that and found out that we can use
cmdrewrite._uncommitdirstate() here. Expect upcoming patches to improve the
documentation of that function.

There are lot of test changes because of change in hash but there is no behavior
change. The only behavior change is in test-evolve-abort-contentdiv.t which is
nice because creating a new commit helps us in stripping that while aborting.
We have a lot of testing of content-divergence and no behavior change gives
enough confidence for making this change.

I reviewed the patch carefully to make sure there is no behavior change and I
suggest reviewer to do the same.

Tests for the --abort flag for `hg evolve` command while content-divergence resolution
======================================================================================

The `--abort` flag aborts the interuppted evolve by undoing all the work which
was done during resolution i.e. stripping new changesets created, moving
bookmarks back, moving working directory back.

This test contains cases when `hg evolve` is doing content-divergence resolution.

Setup
=====

  $ cat >> $HGRCPATH <<EOF
  > [phases]
  > publish = False
  > [alias]
  > glog = log -GT "{rev}:{node|short} {desc}\n ({bookmarks}) {phase}"
  > [extensions]
  > EOF
  $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH

  $ hg init abortrepo
  $ cd abortrepo
  $ echo ".*\.orig" > .hgignore
  $ hg add .hgignore
  $ hg ci -m "added hgignore"
  $ for ch in a b c d; do echo foo > $ch; hg add $ch; hg ci -qm "added "$ch; done;

  $ hg glog
  @  4:c41c793e0ef1 added d
  |   () draft
  o  3:ca1b80f7960a added c
  |   () draft
  o  2:b1661037fa25 added b
  |   () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

Creating content divergence, resolution of which will lead to conflicts
-----------------------------------------------------------------------

  $ echo bar > d
  $ hg amend

  $ hg up c41c793e0ef1 --hidden
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updated to hidden changeset c41c793e0ef1
  (hidden revision 'c41c793e0ef1' was rewritten as: e49523854bc8)
  working directory parent is obsolete! (c41c793e0ef1)
  (use 'hg evolve' to update to its successor: e49523854bc8)

  $ echo foobar > d
  $ hg amend
  2 new content-divergent changesets
  $ hg glog --hidden
  @  6:9c1631e352d9 added d
  |   () draft
  | *  5:e49523854bc8 added d
  |/    () draft
  | x  4:c41c793e0ef1 added d
  |/    () draft
  o  3:ca1b80f7960a added c
  |   () draft
  o  2:b1661037fa25 added b
  |   () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

  $ hg evolve --content-divergent
  merge:[6] added d
  with: [5] added d
  base: [4] added d
  merging "other" content-divergent changeset 'e49523854bc8'
  merging d
  warning: conflicts while merging d! (edit, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  abort: fix conflicts and see `hg help evolve.interrupted`
  [255]

  $ hg status -v
  M d
  # The repository is in an unfinished *evolve* state.
  
  # Unresolved merge conflicts:
  # 
  #     d
  # 
  # To mark files as resolved:  hg resolve --mark FILE
  
  # To continue:    hg evolve --continue
  # To abort:       hg evolve --abort
  # To stop:        hg evolve --stop
  # (also see `hg help evolve.interrupted`)
  

  $ hg evolve --abort
  evolve aborted
  working directory is now at 9c1631e352d9

  $ hg glog --hidden
  @  6:9c1631e352d9 added d
  |   () draft
  | *  5:e49523854bc8 added d
  |/    () draft
  | x  4:c41c793e0ef1 added d
  |/    () draft
  o  3:ca1b80f7960a added c
  |   () draft
  o  2:b1661037fa25 added b
  |   () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

Creating multiple content-divergence where resolution of last one results in
conflicts and resolution of first one resulted in no new commit
-----------------------------------------------------------------------------

  $ echo watbar > d
  $ hg amend
  $ hg up .^
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo bar > c
  $ hg amend
  2 new orphan changesets
  $ hg up ca1b80f7960a --hidden
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  working directory parent is obsolete! (ca1b80f7960a)
  (use 'hg evolve' to update to its successor: 2ba73e31f264)
  $ echo foobar > c
  $ hg amend
  2 new content-divergent changesets
  $ echo bar > c
  $ hg amend

  $ hg glog --hidden
  @  10:491e10505bae added c
  |   () draft
  | x  9:7398f702a162 added c
  |/    () draft
  | *  8:2ba73e31f264 added c
  |/    () draft
  | *  7:f0f1694f123e added d
  | |   () draft
  | | x  6:9c1631e352d9 added d
  | |/    () draft
  | | *  5:e49523854bc8 added d
  | |/    () draft
  | | x  4:c41c793e0ef1 added d
  | |/    () draft
  | x  3:ca1b80f7960a added c
  |/    () draft
  o  2:b1661037fa25 added b
  |   () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

  $ hg evolve --all --content-divergent
  merge:[8] added c
  with: [10] added c
  base: [3] added c
  updating to "local" side of the conflict: 2ba73e31f264
  merging "other" content-divergent changeset '491e10505bae'
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  merge:[5] added d
  with: [7] added d
  base: [4] added d
  updating to "local" side of the conflict: e49523854bc8
  merging "other" content-divergent changeset 'f0f1694f123e'
  merging d
  warning: conflicts while merging d! (edit, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  abort: fix conflicts and see `hg help evolve.interrupted`
  [255]

  $ hg evolve --abort
  2 new content-divergent changesets
  evolve aborted
  working directory is now at 491e10505bae

  $ hg glog --hidden
  @  10:491e10505bae added c
  |   () draft
  | x  9:7398f702a162 added c
  |/    () draft
  | *  8:2ba73e31f264 added c
  |/    () draft
  | *  7:f0f1694f123e added d
  | |   () draft
  | | x  6:9c1631e352d9 added d
  | |/    () draft
  | | *  5:e49523854bc8 added d
  | |/    () draft
  | | x  4:c41c793e0ef1 added d
  | |/    () draft
  | x  3:ca1b80f7960a added c
  |/    () draft
  o  2:b1661037fa25 added b
  |   () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

  $ hg obslog -r . --all
  *  2ba73e31f264 (8) added c
  |
  | @  491e10505bae (10) added c
  | |
  | x  7398f702a162 (9) added c
  |/     rewritten(content) as 491e10505bae using amend by test (Thu Jan 01 00:00:00 1970 +0000)
  |
  x  ca1b80f7960a (3) added c
       rewritten(content) as 2ba73e31f264 using amend by test (Thu Jan 01 00:00:00 1970 +0000)
       rewritten(content) as 7398f702a162 using amend by test (Thu Jan 01 00:00:00 1970 +0000)
  
  $ cd ..

Creating content-divergence on multiple parents when gca of divergent changesets
is parent of one of the divergents and relocating leads to conflicts
---------------------------------------------------------------------------------

  $ hg init multiparent
  $ cd multiparent
  $ echo ".*\.orig" > .hgignore
  $ hg add .hgignore
  $ hg ci -m "added hgignore"
  $ for ch in a b c d; do echo foo > $ch; hg add $ch; hg ci -qm "added "$ch; done;

  $ hg glog
  @  4:c41c793e0ef1 added d
  |   () draft
  o  3:ca1b80f7960a added c
  |   () draft
  o  2:b1661037fa25 added b
  |   () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

  $ hg rebase -r . -d .^^^ --config extensions.rebase=
  rebasing 4:c41c793e0ef1 "added d" (tip)
  $ echo bar > c
  $ hg add c
  $ hg amend

  $ hg up --hidden c41c793e0ef1
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updated to hidden changeset c41c793e0ef1
  (hidden revision 'c41c793e0ef1' was rewritten as: 69bdd23a9b0d)
  working directory parent is obsolete! (c41c793e0ef1)
  (use 'hg evolve' to update to its successor: 69bdd23a9b0d)
  $ echo bar > d
  $ hg amend
  2 new content-divergent changesets

  $ hg glog
  @  7:e49523854bc8 added d
  |   () draft
  | *  6:69bdd23a9b0d added d
  | |   () draft
  o |  3:ca1b80f7960a added c
  | |   () draft
  o |  2:b1661037fa25 added b
  |/    () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

  $ hg evolve --content-divergent
  merge:[7] added d
  with: [6] added d
  base: [4] added d
  rebasing "other" content-divergent changeset 69bdd23a9b0d on ca1b80f7960a
  merging c
  warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
  abort: unresolved merge conflicts (see hg help resolve)
  [255]

  $ hg evolve --abort
  evolve aborted
  working directory is now at e49523854bc8

  $ hg glog
  @  7:e49523854bc8 added d
  |   () draft
  | *  6:69bdd23a9b0d added d
  | |   () draft
  o |  3:ca1b80f7960a added c
  | |   () draft
  o |  2:b1661037fa25 added b
  |/    () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

Creating content-divergence on multiple parents when gca of divergent changesets
is parent of one of the divergents and merging divergent leads to conflicts
---------------------------------------------------------------------------------

  $ hg up 69bdd23a9b0d
  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg rm c
  $ echo wat > d
  $ hg amend

  $ hg glog
  @  8:33e4442acf98 added d
  |   () draft
  | *  7:e49523854bc8 added d
  | |   () draft
  | o  3:ca1b80f7960a added c
  | |   () draft
  | o  2:b1661037fa25 added b
  |/    () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft

  $ hg evolve --content-divergent
  merge:[7] added d
  with: [8] added d
  base: [4] added d
  rebasing "other" content-divergent changeset 33e4442acf98 on ca1b80f7960a
  updating to "local" side of the conflict: e49523854bc8
  merging "other" content-divergent changeset 'a663d1567f0b'
  merging d
  warning: conflicts while merging d! (edit, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  abort: fix conflicts and see `hg help evolve.interrupted`
  [255]

  $ hg evolve --abort
  evolve aborted
  working directory is now at 33e4442acf98

  $ hg glog
  @  8:33e4442acf98 added d
  |   () draft
  | *  7:e49523854bc8 added d
  | |   () draft
  | o  3:ca1b80f7960a added c
  | |   () draft
  | o  2:b1661037fa25 added b
  |/    () draft
  o  1:c7586e2a9264 added a
  |   () draft
  o  0:8fa14d15e168 added hgignore
      () draft