view tests/test-evolve-topic.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.

Check we can find the topic extensions

  $ cat >> $HGRCPATH <<EOF
  > [defaults]
  > amend=-d "0 0"
  > fold=-d "0 0"
  > [phases]
  > publish = False
  > [ui]
  > logtemplate = {rev} - \{{get(namespaces, "topics")}} {node|short} {desc} ({phase})\n
  > [diff]
  > git = 1
  > unified = 0
  > [extensions]
  > rebase = 
  > EOF
  $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
  $ echo "topic=$(echo $(dirname $TESTDIR))/hgext3rd/topic/" >> $HGRCPATH

  $ mkcommit() {
  >    echo "$1" > "$1"
  >    hg add "$1"
  >    hg ci -m "add $1"
  > }

Create a simple setup

  $ hg init repoa
  $ cd repoa
  $ mkcommit aaa
  $ mkcommit bbb
  $ hg topic foo
  marked working directory as topic: foo
  $ mkcommit ccc
  active topic 'foo' grew its first changeset
  (see 'hg help topics' for more information)
  $ mkcommit ddd
  $ mkcommit eee
  $ mkcommit fff
  $ hg topic bar
  $ mkcommit ggg
  active topic 'bar' grew its first changeset
  (see 'hg help topics' for more information)
  $ mkcommit hhh
  $ mkcommit iii
  $ mkcommit jjj

  $ hg log -G
  @  9 - {bar} 1d964213b023 add jjj (draft)
  |
  o  8 - {bar} fcab990f3261 add iii (draft)
  |
  o  7 - {bar} b0c2554835ac add hhh (draft)
  |
  o  6 - {bar} c748293f1c1a add ggg (draft)
  |
  o  5 - {foo} 6a6b7365c751 add fff (draft)
  |
  o  4 - {foo} 3969ab847d9c add eee (draft)
  |
  o  3 - {foo} 4e3a154f38c7 add ddd (draft)
  |
  o  2 - {foo} cced9bac76e3 add ccc (draft)
  |
  o  1 - {} a4dbed0837ea add bbb (draft)
  |
  o  0 - {} 199cc73e9a0b add aaa (draft)
  

Test that evolve --all evolve the current topic
-----------------------------------------------

make a mess

  $ hg up foo
  switching to topic foo
  0 files updated, 0 files merged, 4 files removed, 0 files unresolved
  $ hg topic -l 
  ### topic: foo (?)
  ### branch: default (?)
  ### target: default (branch)
  t4@ add fff (current)
  t3: add eee
  t2: add ddd
  t1: add ccc
  t0^ add bbb (base)
  $ hg up 'desc(ddd)'
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo ddd >> ddd
  $ hg amend
  6 new orphan changesets
  $ hg up 'desc(fff)'
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo fff >> fff
  $ hg amend

  $ hg log -G
  @  11 - {foo} e104f49bab28 add fff (draft)
  |
  | o  10 - {foo} d9cacd156ffc add ddd (draft)
  | |
  | | *  9 - {bar} 1d964213b023 add jjj (draft)
  | | |
  | | *  8 - {bar} fcab990f3261 add iii (draft)
  | | |
  | | *  7 - {bar} b0c2554835ac add hhh (draft)
  | | |
  | | *  6 - {bar} c748293f1c1a add ggg (draft)
  | | |
  +---x  5 - {foo} 6a6b7365c751 add fff (draft)
  | |
  * |  4 - {foo} 3969ab847d9c add eee (draft)
  | |
  x |  3 - {foo} 4e3a154f38c7 add ddd (draft)
  |/
  o  2 - {foo} cced9bac76e3 add ccc (draft)
  |
  o  1 - {} a4dbed0837ea add bbb (draft)
  |
  o  0 - {} 199cc73e9a0b add aaa (draft)
  

Run evolve --all

  $ hg evolve --all
  move:[4] add eee
  atop:[10] add ddd
  move:[11] add fff
  atop:[12] add eee
  working directory is now at 070c5573d8f9
  $ hg log -G
  @  13 - {foo} 070c5573d8f9 add fff (draft)
  |
  o  12 - {foo} 42b49017ff90 add eee (draft)
  |
  o  10 - {foo} d9cacd156ffc add ddd (draft)
  |
  | *  9 - {bar} 1d964213b023 add jjj (draft)
  | |
  | *  8 - {bar} fcab990f3261 add iii (draft)
  | |
  | *  7 - {bar} b0c2554835ac add hhh (draft)
  | |
  | *  6 - {bar} c748293f1c1a add ggg (draft)
  | |
  | x  5 - {foo} 6a6b7365c751 add fff (draft)
  | |
  | x  4 - {foo} 3969ab847d9c add eee (draft)
  | |
  | x  3 - {foo} 4e3a154f38c7 add ddd (draft)
  |/
  o  2 - {foo} cced9bac76e3 add ccc (draft)
  |
  o  1 - {} a4dbed0837ea add bbb (draft)
  |
  o  0 - {} 199cc73e9a0b add aaa (draft)
  

Test that evolve does not loose topic information
-------------------------------------------------

  $ hg evolve --rev 'topic(bar)'
  move:[6] add ggg
  atop:[13] add fff
  move:[7] add hhh
  atop:[14] add ggg
  move:[8] add iii
  atop:[15] add hhh
  move:[9] add jjj
  atop:[16] add iii
  working directory is now at 9bf430c106b7
  $ hg log -G
  @  17 - {bar} 9bf430c106b7 add jjj (draft)
  |
  o  16 - {bar} d2dc89c57700 add iii (draft)
  |
  o  15 - {bar} 20bc4d02aa62 add hhh (draft)
  |
  o  14 - {bar} 16d6f664b17c add ggg (draft)
  |
  o  13 - {foo} 070c5573d8f9 add fff (draft)
  |
  o  12 - {foo} 42b49017ff90 add eee (draft)
  |
  o  10 - {foo} d9cacd156ffc add ddd (draft)
  |
  o  2 - {foo} cced9bac76e3 add ccc (draft)
  |
  o  1 - {} a4dbed0837ea add bbb (draft)
  |
  o  0 - {} 199cc73e9a0b add aaa (draft)
  

Tests next and prev behavior
============================

Basic move are restricted to the current topic

  $ hg up foo
  switching to topic foo
  0 files updated, 0 files merged, 4 files removed, 0 files unresolved
  $ hg prev
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  [12] add eee
  $ hg next
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  [13] add fff
  $ hg next
  no children on topic "foo"
  do you want --no-topic
  [1]
  $ hg next --no-topic
  switching to topic bar
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  [14] add ggg
  $ hg prev
  preserving the current topic 'bar'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  [13] add fff
  $ hg prev
  no parent in topic "bar"
  (do you want --no-topic)
  [1]
  $ hg prev --no-topic
  switching to topic foo
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  [12] add eee

Testing when instability is involved

  $ hg log -G
  o  17 - {bar} 9bf430c106b7 add jjj (draft)
  |
  o  16 - {bar} d2dc89c57700 add iii (draft)
  |
  o  15 - {bar} 20bc4d02aa62 add hhh (draft)
  |
  o  14 - {bar} 16d6f664b17c add ggg (draft)
  |
  o  13 - {foo} 070c5573d8f9 add fff (draft)
  |
  @  12 - {foo} 42b49017ff90 add eee (draft)
  |
  o  10 - {foo} d9cacd156ffc add ddd (draft)
  |
  o  2 - {foo} cced9bac76e3 add ccc (draft)
  |
  o  1 - {} a4dbed0837ea add bbb (draft)
  |
  o  0 - {} 199cc73e9a0b add aaa (draft)
  
  $ hg topic -r 070c5573d8f9 bar
  4 new orphan changesets
  changed topic on 1 changes
  $ hg up 16d6f664b17c
  switching to topic bar
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg stack
  ### topic: bar
  ### target: default (branch)
  t5$ add jjj (unstable)
  t4$ add iii (unstable)
  t3$ add hhh (unstable)
  t2$ add ggg (current unstable)
  t1: add fff
  t0^ add eee (base)

  $ hg prev
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  [18] add fff

Testing issue 5708 when we are on obsolete changeset and there is active topic
------------------------------------------------------------------------------

  $ hg log --graph
  @  18 - {bar} 793eb6370b2d add fff (draft)
  |
  | *  17 - {bar} 9bf430c106b7 add jjj (draft)
  | |
  | *  16 - {bar} d2dc89c57700 add iii (draft)
  | |
  | *  15 - {bar} 20bc4d02aa62 add hhh (draft)
  | |
  | *  14 - {bar} 16d6f664b17c add ggg (draft)
  | |
  | x  13 - {foo} 070c5573d8f9 add fff (draft)
  |/
  o  12 - {foo} 42b49017ff90 add eee (draft)
  |
  o  10 - {foo} d9cacd156ffc add ddd (draft)
  |
  o  2 - {foo} cced9bac76e3 add ccc (draft)
  |
  o  1 - {} a4dbed0837ea add bbb (draft)
  |
  o  0 - {} 199cc73e9a0b add aaa (draft)
  

  $ hg topic
   * bar (5 changesets, 4 troubled)
     foo (3 changesets)

When the current topic, obsoleted changesets topic and successor topic are same

  $ hg up 20bc4d02aa62
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo foobar >> hhh
  $ hg amend
  $ hg up 20bc4d02aa62
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  working directory parent is obsolete! (20bc4d02aa62)
  (use 'hg evolve' to update to its successor: d834582d9ee3)
  $ hg log -Gr 14::
  *  19 - {bar} d834582d9ee3 add hhh (draft)
  |
  | *  17 - {bar} 9bf430c106b7 add jjj (draft)
  | |
  | *  16 - {bar} d2dc89c57700 add iii (draft)
  | |
  | @  15 - {bar} 20bc4d02aa62 add hhh (draft)
  |/
  *  14 - {bar} 16d6f664b17c add ggg (draft)
  |
  ~

  $ hg prev
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  [14] add ggg

When the current topic and successors topic are same, but obsolete cset has
different topic

  $ hg rebase -s d2dc89c57700 -d d834582d9ee3 --config extensions.rebase=
  rebasing 16:d2dc89c57700 "add iii" (bar)
  1 new orphan changesets
  rebasing 17:9bf430c106b7 "add jjj" (bar)
  1 new orphan changesets
  $ hg log -Gr 42b49017ff90::
  *  21 - {bar} 7542e76aba2c add jjj (draft)
  |
  *  20 - {bar} 7858bd7e9906 add iii (draft)
  |
  *  19 - {bar} d834582d9ee3 add hhh (draft)
  |
  | o  18 - {bar} 793eb6370b2d add fff (draft)
  | |
  @ |  14 - {bar} 16d6f664b17c add ggg (draft)
  | |
  x |  13 - {foo} 070c5573d8f9 add fff (draft)
  |/
  o  12 - {foo} 42b49017ff90 add eee (draft)
  |
  ~

  $ hg up 070c5573d8f9
  switching to topic foo
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  working directory parent is obsolete! (070c5573d8f9)
  (use 'hg evolve' to update to its successor: 793eb6370b2d)

  $ hg topic bar

  $ hg prev
  no parent in topic "bar"
  (do you want --no-topic)
  [1]

When current topic and obsolete cset topic are same but successor has different
one

  $ hg up 070c5573d8f9
  switching to topic foo
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg prev
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  [12] add eee