view tests/test-wireproto.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.

  $ cat >> $HGRCPATH <<EOF
  > [defaults]
  > amend=-d "0 0"
  > [experimental]
  > obsmarkers-exchange-debug=true
  > bundle2-exp=true
  > [ui]
  > ssh=python "$RUNTESTDIR/dummyssh"
  > [phases]
  > publish = False
  > [extensions]
  > EOF
  $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH

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

setup repo

  $ hg init server

  $ hg clone ssh://user@dummy/server client
  no changes found
  updating to branch default
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cp -r client other

Smoke testing
===============.t

  $ cd client
  $ mkcommit 0
  $ mkcommit a
  $ hg push
  pushing to ssh://user@dummy/server
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 2 changesets with 2 changes to 2 files
  $ hg pull
  pulling from ssh://user@dummy/server
  searching for changes
  no changes found
  $ hg pull -R ../other
  pulling from ssh://user@dummy/server
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets 8685c6d34325:4957bfdac07e
  (run 'hg update' to get a working copy)
  $ hg push -R ../other
  pushing to ssh://user@dummy/server
  searching for changes
  no changes found
  [1]

Push
=============

  $ echo 'A' > a
  $ hg amend
  $ hg push
  pushing to ssh://user@dummy/server
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 1 changes to 1 files (+1 heads)
  remote: obsmarker-exchange: 92 bytes received
  remote: 1 new obsolescence markers
  remote: obsoleted 1 changesets
  $ hg push
  pushing to ssh://user@dummy/server
  searching for changes
  no changes found
  [1]

Pull
=============

  $ hg -R ../other pull
  pulling from ssh://user@dummy/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to [12] files \(\+1 heads\) (re)
  obsmarker-exchange: 92 bytes received
  1 new obsolescence markers
  obsoleted 1 changesets
  new changesets 9d1c114e7797
  (run 'hg heads' to see heads)
  $ hg -R ../other pull
  pulling from ssh://user@dummy/server
  searching for changes
  no changes found

Test some markers discovery
===========================

  $ echo c > C
  $ hg add C
  $ hg commit -m C
  $ echo c >> C
  $ hg amend
  $ hg push
  pushing to ssh://user@dummy/server
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 1 changes to 1 files
  remote: obsmarker-exchange: 92 bytes received
  remote: 1 new obsolescence markers
  $ hg -R ../other pull
  pulling from ssh://user@dummy/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  obsmarker-exchange: 92 bytes received
  1 new obsolescence markers
  new changesets a5687ec59dd4
  (run 'hg update' to get a working copy)

some common hidden

  $ hg touch .
  $ hg push
  pushing to ssh://user@dummy/server
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 0 changes to 1 files (+1 heads)
  remote: obsmarker-exchange: 183 bytes received
  remote: 1 new obsolescence markers
  remote: obsoleted 1 changesets
  $ hg -R ../other pull
  pulling from ssh://user@dummy/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 1 files (+1 heads)
  obsmarker-exchange: 183 bytes received
  1 new obsolescence markers
  obsoleted 1 changesets
  new changesets * (glob)
  (run 'hg heads' to see heads)

test discovery avoid exchanging known markers

  $ hg push
  pushing to ssh://user@dummy/server
  searching for changes
  no changes found
  [1]
  $ hg -R ../other pull
  pulling from ssh://user@dummy/server
  searching for changes
  no changes found

test discovery can be disabled

  $ hg push --config experimental.evolution.obsdiscovery=no
  pushing to ssh://user@dummy/server
  searching for changes
  (skipping discovery of obsolescence markers, will exchange everything)
  (controled by 'experimental.evolution.obsdiscovery' configuration)
  no changes found
  remote: obsmarker-exchange: 274 bytes received
  [1]
  $ hg -R ../other pull --config experimental.evolution.obsdiscovery=no
  pulling from ssh://user@dummy/server
  searching for changes
  no changes found
  (skipping discovery of obsolescence markers, will exchange everything)
  (controled by 'experimental.evolution.obsdiscovery' configuration)
  obsmarker-exchange: 274 bytes received

  $ cd ..

And disable it server side too:

  $ hg serve -R server -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log  --config experimental.evolution.obsdiscovery=no
  $ cat hg.pid >> $DAEMON_PIDS

  $ curl -s http://localhost:$HGPORT/?cmd=capabilities
  _evoext_getbundle_obscommon batch branchmap bundle2=HG20%0Abookmarks%0Achangegroup%3D01%2C02%0Adigests%3Dmd5%2Csha1%2Csha512%0Aerror%3Dabort%2Cunsupportedcontent%2Cpushraced%2Cpushkey%0Ahgtagsfnodes%0Alistkeys%0Aobsmarkers%3DV0%2CV1%0Aphases%3Dheads%0Apushkey%0Aremote-changegroup%3Dhttp%2Chttps%0Arev-branch-cache changegroupsubset compression=*zlib getbundle httpheader=1024 httpmediatype=0.1rx,0.1tx,0.2tx known lookup pushkey streamreqs=generaldelta,revlogv1 unbundle=HG10GZ,HG10BZ,HG10UN unbundlehash (no-eol) (glob)

Check we cannot use pushkey for marker exchange anymore

  $ hg debugpushkey http://localhost:$HGPORT/ obsolete
  abort: HTTP Error 410: won't exchange obsmarkers through pushkey
  [255]
  $ cat errors.log
  $ hg debugpushkey ssh://user@dummy/server obsolete
  remote: abort: won't exchange obsmarkers through pushkey
  remote: (upgrade your client or server to use the bundle2 protocol)
  abort: unexpected response: empty string
  [255]

(do some extra pulling to be sure)

  $ hg -R client pull http://localhost:$HGPORT/
  pulling from http://localhost:$HGPORT/
  searching for changes
  no changes found
  obsmarker-exchange: 274 bytes received

  $ hg -R client pull http://localhost:$HGPORT/ --config experimental.evolution=createmarkers
  pulling from http://localhost:$HGPORT/
  searching for changes
  no changes found

  $ hg -R client pull http://localhost:$HGPORT/ --config experimental.evolution=createmarkers --config extensions.evolve='!'
  pulling from http://localhost:$HGPORT/
  searching for changes
  no changes found

But we do let it goes fine on repository with exchange disabled:

  $ $RUNTESTDIR/killdaemons.py $DAEMON_PIDS
  $ hg serve -R server -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log  --config experimental.evolution='!'
  $ hg debugpushkey http://localhost:$HGPORT/ obsolete

(do some extra pulling to be sure)

  $ hg -R client pull http://localhost:$HGPORT/
  pulling from http://localhost:$HGPORT/
  searching for changes
  no changes found

  $ hg -R client pull http://localhost:$HGPORT/ --config experimental.evolution=createmarkers
  pulling from http://localhost:$HGPORT/
  searching for changes
  no changes found

  $ hg -R client pull http://localhost:$HGPORT/ --config experimental.evolution=createmarkers --config extensions.evolve='!'
  pulling from http://localhost:$HGPORT/
  searching for changes
  no changes found

  $ $RUNTESTDIR/killdaemons.py $DAEMON_PIDS