view tests/test-copies-chain-merge.t @ 44763:94f4f2ec7dee stable

packaging: support building Inno installer with PyOxidizer

We want to start distributing Mercurial on Python 3 on
Windows. PyOxidizer will be our vehicle for achieving that.

This commit implements basic support for producing Inno
installers using PyOxidizer.

While it is an eventual goal of PyOxidizer to produce
installers, those features aren't yet implemented. So our
strategy for producing Mercurial installers is similar to
what we've been doing with py2exe: invoke a build system to
produce files then stage those files into a directory so they
can be turned into an installer.

We had to make significant alterations to the pyoxidizer.bzl
config file to get it to produce the files that we desire for
a Windows install. This meant differentiating the build targets
so we can target Windows specifically.

We've added a new module to hgpackaging to deal with interacting
with PyOxidizer. It is similar to pyexe: we invoke a build process
then copy files to a staging directory. Ideally these extra
files would be defined in pyoxidizer.bzl. But I don't think it
is worth doing at this time, as PyOxidizer's config files are
lacking some features to make this turnkey.

The rest of the change is introducing a variant of the
Inno installer code that invokes PyOxidizer instead of
py2exe.

Comparing the Python 2.7 based Inno installers with this
one, the following changes were observed:

* No lib/*.{pyd, dll} files
* No Microsoft.VC90.CRT.manifest
* No msvc{m,p,r}90.dll files
* python27.dll replaced with python37.dll
* Add vcruntime140.dll file

The disappearance of the .pyd and .dll files is acceptable, as
PyOxidizer has embedded these in hg.exe and loads them from
memory.

The disappearance of the *90* files is acceptable because those
provide the Visual C++ 9 runtime, as required by Python 2.7.
Similarly, the appearance of vcruntime140.dll is a requirement
of Python 3.7.

Differential Revision: https://phab.mercurial-scm.org/D8473

=====================================================
Test Copy tracing for chain of copies involving merge
=====================================================

This test files covers copies/rename case for a chains of commit where merges
are involved. It cheks we do not have unwanted update of behavior and that the
different options to retrieve copies behave correctly.

Setup
=====

use git diff to see rename

  $ cat << EOF >> $HGRCPATH
  > [diff]
  > git=yes
  > [ui]
  > logtemplate={rev} {desc}\n
  > EOF

  $ hg init repo-chain
  $ cd repo-chain

Add some linear rename initialy

  $ touch a b h
  $ hg ci -Am 'i-0 initial commit: a b h'
  adding a
  adding b
  adding h
  $ hg mv a c
  $ hg ci -Am 'i-1: a -move-> c'
  $ hg mv c d
  $ hg ci -Am 'i-2: c -move-> d'
  $ hg log -G
  @  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  

And having another branch with renames on the other side

  $ hg mv d e
  $ hg ci -Am 'a-1: d -move-> e'
  $ hg mv e f
  $ hg ci -Am 'a-2: e -move-> f'
  $ hg log -G --rev '::.'
  @  4 a-2: e -move-> f
  |
  o  3 a-1: d -move-> e
  |
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  

Have a branching with nothing on one side

  $ hg up 'desc("i-2")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo foo > b
  $ hg ci -m 'b-1: b update'
  created new head
  $ hg log -G --rev '::.'
  @  5 b-1: b update
  |
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  

Create a branch that delete a file previous renamed

  $ hg up 'desc("i-2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg rm d
  $ hg ci -m 'c-1 delete d'
  created new head
  $ hg log -G --rev '::.'
  @  6 c-1 delete d
  |
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  

Create a branch that delete a file previous renamed and recreate it

  $ hg up 'desc("i-2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg rm d
  $ hg ci -m 'd-1 delete d'
  created new head
  $ echo bar > d
  $ hg add d
  $ hg ci -m 'd-2 re-add d'
  $ hg log -G --rev '::.'
  @  8 d-2 re-add d
  |
  o  7 d-1 delete d
  |
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  

Having another branch renaming a different file to the same filename as another

  $ hg up 'desc("i-2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg mv b g
  $ hg ci -m 'e-1 b -move-> g'
  created new head
  $ hg mv g f
  $ hg ci -m 'e-2 g -move-> f'
  $ hg log -G --rev '::.'
  @  10 e-2 g -move-> f
  |
  o  9 e-1 b -move-> g
  |
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  

merging with unrelated change does not interfere with the renames
---------------------------------------------------------------

- rename on one side
- unrelated change on the other side

  $ hg up 'desc("b-1")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg merge 'desc("a-2")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mBAm-0 simple merge - one way'
  $ hg up 'desc("a-2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("b-1")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mABm-0 simple merge - the other way'
  created new head
  $ hg log -G --rev '::(desc("mABm")+desc("mBAm"))'
  @    12 mABm-0 simple merge - the other way
  |\
  +---o  11 mBAm-0 simple merge - one way
  | |/
  | o  5 b-1: b update
  | |
  o |  4 a-2: e -move-> f
  | |
  o |  3 a-1: d -move-> e
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  

  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mABm")'
  A f
    d
  R d
  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mBAm")'
  A f
    d
  R d
  $ hg status --copies --rev 'desc("a-2")' --rev 'desc("mABm")'
  M b
  $ hg status --copies --rev 'desc("a-2")' --rev 'desc("mBAm")'
  M b
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mABm")'
  M b
  A f
    d
  R d
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mBAm")'
  M b
  A f
    d
  R d
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mABm")'
  M b
  A f
    a
  R a
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mBAm")'
  M b
  A f
    a
  R a

merging with the side having a delete
-------------------------------------

case summary:
- one with change to an unrelated file
- one deleting the change
and recreate an unrelated file after the merge

  $ hg up 'desc("b-1")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg merge 'desc("c-1")'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mBCm-0 simple merge - one way'
  $ echo bar > d
  $ hg add d
  $ hg ci -m 'mBCm-1 re-add d'
  $ hg up 'desc("c-1")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg merge 'desc("b-1")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mCBm-0 simple merge - the other way'
  created new head
  $ echo bar > d
  $ hg add d
  $ hg ci -m 'mCBm-1 re-add d'
  $ hg log -G --rev '::(desc("mCBm")+desc("mBCm"))'
  @  16 mCBm-1 re-add d
  |
  o    15 mCBm-0 simple merge - the other way
  |\
  | | o  14 mBCm-1 re-add d
  | | |
  +---o  13 mBCm-0 simple merge - one way
  | |/
  | o  6 c-1 delete d
  | |
  o |  5 b-1: b update
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  
- comparing from the merge

  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mBCm-0")'
  R d
  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mCBm-0")'
  R d
  $ hg status --copies --rev 'desc("c-1")' --rev 'desc("mBCm-0")'
  M b
  $ hg status --copies --rev 'desc("c-1")' --rev 'desc("mCBm-0")'
  M b
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mBCm-0")'
  M b
  R d
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mCBm-0")'
  M b
  R d
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mBCm-0")'
  M b
  R a
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mCBm-0")'
  M b
  R a

- comparing with the merge children re-adding the file

  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mBCm-1")'
  M d
  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mCBm-1")'
  M d
  $ hg status --copies --rev 'desc("c-1")' --rev 'desc("mBCm-1")'
  M b
  A d
  $ hg status --copies --rev 'desc("c-1")' --rev 'desc("mCBm-1")'
  M b
  A d
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mBCm-1")'
  M b
  M d
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mCBm-1")'
  M b
  M d
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mBCm-1")'
  M b
  A d
  R a
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mCBm-1")'
  M b
  A d
  R a

Comparing with a merge re-adding the file afterward
---------------------------------------------------

Merge:
- one with change to an unrelated file
- one deleting and recreating the change

Note:
| In this case, one of the merge wrongly record a merge while there is none.
| This lead to bad copy tracing information to be dug up.

  $ hg up 'desc("b-1")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("d-2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mBDm-0 simple merge - one way'
  $ hg up 'desc("d-2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("b-1")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mDBm-0 simple merge - the other way'
  created new head
  $ hg log -G --rev '::(desc("mDBm")+desc("mBDm"))'
  @    18 mDBm-0 simple merge - the other way
  |\
  +---o  17 mBDm-0 simple merge - one way
  | |/
  | o  8 d-2 re-add d
  | |
  | o  7 d-1 delete d
  | |
  o |  5 b-1: b update
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  
  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mBDm-0")'
  M d
  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mDBm-0")'
  M d
  $ hg status --copies --rev 'desc("d-2")' --rev 'desc("mBDm-0")'
  M b
  $ hg status --copies --rev 'desc("d-2")' --rev 'desc("mDBm-0")'
  M b
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mBDm-0")'
  M b
  M d
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mDBm-0")'
  M b
  M d

The bugs makes recorded copy is different depending of where we started the merge from since

  $ hg manifest --debug --rev 'desc("mBDm-0")' | grep '644   d'
  b004912a8510032a0350a74daa2803dadfb00e12 644   d
  $ hg manifest --debug --rev 'desc("mDBm-0")' | grep '644   d'
  b004912a8510032a0350a74daa2803dadfb00e12 644   d

The 0bb5445dc4d02f4e0d86cf16f9f3a411d0f17744 entry is wrong, since the file was
deleted on one side (then recreate) and untouched on the other side, no "merge"
has happened. The resulting `d` file is the untouched version from branch `D`,
not a merge.

  $ hg manifest --debug --rev 'desc("d-2")' | grep '644   d'
  b004912a8510032a0350a74daa2803dadfb00e12 644   d
  $ hg manifest --debug --rev 'desc("b-1")' | grep '644   d'
  01c2f5eabdc4ce2bdee42b5f86311955e6c8f573 644   d
  $ hg debugindex d
     rev linkrev nodeid       p1           p2
       0       2 01c2f5eabdc4 000000000000 000000000000
       1       8 b004912a8510 000000000000 000000000000

(This `hg log` output if wrong, since no merge actually happened).

  $ hg log -Gfr 'desc("mBDm-0")' d
  o  8 d-2 re-add d
  |
  ~

This `hg log` output is correct

  $ hg log -Gfr 'desc("mDBm-0")' d
  o  8 d-2 re-add d
  |
  ~

  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mBDm-0")'
  M b
  A d
  R a
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mDBm-0")'
  M b
  A d
  R a


Comparing with a merge with colliding rename
--------------------------------------------

- the "e-" branch renaming b to f (through 'g')
- the "a-" branch renaming d to f (through e)

  $ hg up 'desc("a-2")'
  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg merge 'desc("e-2")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mAEm-0 simple merge - one way'
  $ hg up 'desc("e-2")'
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("a-2")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mEAm-0 simple merge - the other way'
  created new head
  $ hg log -G --rev '::(desc("mAEm")+desc("mEAm"))'
  @    20 mEAm-0 simple merge - the other way
  |\
  +---o  19 mAEm-0 simple merge - one way
  | |/
  | o  10 e-2 g -move-> f
  | |
  | o  9 e-1 b -move-> g
  | |
  o |  4 a-2: e -move-> f
  | |
  o |  3 a-1: d -move-> e
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  
  $ hg manifest --debug --rev 'desc("mAEm-0")' | grep '644   f'
  eb806e34ef6be4c264effd5933d31004ad15a793 644   f
  $ hg manifest --debug --rev 'desc("mEAm-0")' | grep '644   f'
  eb806e34ef6be4c264effd5933d31004ad15a793 644   f
  $ hg manifest --debug --rev 'desc("a-2")' | grep '644   f'
  0dd616bc7ab1a111921d95d76f69cda5c2ac539c 644   f
  $ hg manifest --debug --rev 'desc("e-2")' | grep '644   f'
  6da5a2eecb9c833f830b67a4972366d49a9a142c 644   f
  $ hg debugindex f
     rev linkrev nodeid       p1           p2
       0       4 0dd616bc7ab1 000000000000 000000000000
       1      10 6da5a2eecb9c 000000000000 000000000000
       2      19 eb806e34ef6b 0dd616bc7ab1 6da5a2eecb9c
  $ hg status --copies --rev 'desc("a-2")' --rev 'desc("mAEm-0")'
  M f
  R b
  $ hg status --copies --rev 'desc("a-2")' --rev 'desc("mEAm-0")'
  M f
  R b
  $ hg status --copies --rev 'desc("e-2")' --rev 'desc("mAEm-0")'
  M f
  R d
  $ hg status --copies --rev 'desc("e-2")' --rev 'desc("mEAm-0")'
  M f
  R d
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("a-2")'
  A f
    d
  R d
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("e-2")'
  A f
    b
  R b
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mAEm-0")'
  A f
    d
  R b
  R d
  $ hg status --copies --rev 'desc("i-2")' --rev 'desc("mEAm-0")'
  A f
    d
  R b
  R d
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mAEm-0")'
  A f
    a
  R a
  R b
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mEAm-0")'
  A f
    a
  R a
  R b


Note:
| In this case, one of the merge wrongly record a merge while there is none.
| This lead to bad copy tracing information to be dug up.


Merge:
- one with change to an unrelated file (b)
- one overwriting a file (d) with a rename (from h to i to d)

  $ hg up 'desc("i-2")'
  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg mv h i
  $ hg commit -m "f-1: rename h -> i"
  created new head
  $ hg mv --force i d
  $ hg commit -m "f-2: rename i -> d"
  $ hg debugindex d
     rev linkrev nodeid       p1           p2
       0       2 01c2f5eabdc4 000000000000 000000000000
       1       8 b004912a8510 000000000000 000000000000
       2      22 c72365ee036f 000000000000 000000000000
  $ hg up 'desc("b-1")'
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("f-2")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mBFm-0 simple merge - one way'
  $ hg up 'desc("f-2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("b-1")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mFBm-0 simple merge - the other way'
  created new head
  $ hg log -G --rev '::(desc("mBFm")+desc("mFBm"))'
  @    24 mFBm-0 simple merge - the other way
  |\
  +---o  23 mBFm-0 simple merge - one way
  | |/
  | o  22 f-2: rename i -> d
  | |
  | o  21 f-1: rename h -> i
  | |
  o |  5 b-1: b update
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  
The overwriting should take over. However, the behavior is currently buggy

  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mBFm-0")'
  M b
  A d
    h
    h (false !)
  R a
  R h
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mFBm-0")'
  M b
  A d
    h
  R a
  R h
  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mBFm-0")'
  M d
  R h
  $ hg status --copies --rev 'desc("f-2")' --rev 'desc("mBFm-0")'
  M b
  $ hg status --copies --rev 'desc("f-1")' --rev 'desc("mBFm-0")'
  M b
  M d
  R i
  $ hg status --copies --rev 'desc("b-1")' --rev 'desc("mFBm-0")'
  M d
  R h
  $ hg status --copies --rev 'desc("f-2")' --rev 'desc("mFBm-0")'
  M b
  $ hg status --copies --rev 'desc("f-1")' --rev 'desc("mFBm-0")'
  M b
  M d
  R i

The following graphlog is wrong, the "a -> c -> d" chain was overwritten and should not appear.

  $ hg log -Gfr 'desc("mBFm-0")' d
  o  22 f-2: rename i -> d
  |
  o  21 f-1: rename h -> i
  :
  o  0 i-0 initial commit: a b h
  

The following output is correct.

  $ hg log -Gfr 'desc("mFBm-0")' d
  o  22 f-2: rename i -> d
  |
  o  21 f-1: rename h -> i
  :
  o  0 i-0 initial commit: a b h
  


Merge:
- one with change to a file
- one deleting and recreating the file

Unlike in the 'BD/DB' cases, an actual merge happened here. So we should
consider history and rename on both branch of the merge.

  $ hg up 'desc("i-2")'
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo "some update" >> d
  $ hg commit -m "g-1: update d"
  created new head
  $ hg up 'desc("d-2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("g-1")' --tool :union
  merging d
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mDGm-0 simple merge - one way'
  $ hg up 'desc("g-1")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("d-2")' --tool :union
  merging d
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mGDm-0 simple merge - the other way'
  created new head
  $ hg log -G --rev '::(desc("mDGm")+desc("mGDm"))'
  @    27 mGDm-0 simple merge - the other way
  |\
  +---o  26 mDGm-0 simple merge - one way
  | |/
  | o  25 g-1: update d
  | |
  o |  8 d-2 re-add d
  | |
  o |  7 d-1 delete d
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mDGm-0")'
  A d
    a
  R a
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mGDm-0")'
  A d
    a
  R a
  $ hg status --copies --rev 'desc("d-2")' --rev 'desc("mDGm-0")'
  M d
  $ hg status --copies --rev 'desc("d-2")' --rev 'desc("mGDm-0")'
  M d
  $ hg status --copies --rev 'desc("g-1")' --rev 'desc("mDGm-0")'
  M d
  $ hg status --copies --rev 'desc("g-1")' --rev 'desc("mGDm-0")'
  M d

  $ hg log -Gfr 'desc("mDGm-0")' d
  o    26 mDGm-0 simple merge - one way
  |\
  | o  25 g-1: update d
  | |
  o |  8 d-2 re-add d
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  


  $ hg log -Gfr 'desc("mDGm-0")' d
  o    26 mDGm-0 simple merge - one way
  |\
  | o  25 g-1: update d
  | |
  o |  8 d-2 re-add d
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  


Merge:
- one with change to a file (d)
- one overwriting that file with a rename (from h to i, to d)

This case is similar to BF/FB, but an actual merge happens, so both side of the
history are relevant.

Note:
| In this case, the merge get conflicting information since on one side we have
| "a -> c -> d". and one the other one we have "h -> i -> d".
|
| The current code arbitrarily pick one side

  $ hg up 'desc("f-2")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg merge 'desc("g-1")' --tool :union
  merging d
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mFGm-0 simple merge - one way'
  created new head
  $ hg up 'desc("g-1")'
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge 'desc("f-2")' --tool :union
  merging d
  0 files updated, 1 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'mGFm-0 simple merge - the other way'
  created new head
  $ hg log -G --rev '::(desc("mGFm")+desc("mFGm"))'
  @    29 mGFm-0 simple merge - the other way
  |\
  +---o  28 mFGm-0 simple merge - one way
  | |/
  | o  25 g-1: update d
  | |
  o |  22 f-2: rename i -> d
  | |
  o |  21 f-1: rename h -> i
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mFGm-0")'
  A d
    a
  R a
  R h
  $ hg status --copies --rev 'desc("i-0")' --rev 'desc("mGFm-0")'
  A d
    a
  R a
  R h
  $ hg status --copies --rev 'desc("f-2")' --rev 'desc("mFGm-0")'
  M d
  $ hg status --copies --rev 'desc("f-2")' --rev 'desc("mGFm-0")'
  M d
  $ hg status --copies --rev 'desc("f-1")' --rev 'desc("mFGm-0")'
  M d
  R i
  $ hg status --copies --rev 'desc("f-1")' --rev 'desc("mGFm-0")'
  M d
  R i
  $ hg status --copies --rev 'desc("g-1")' --rev 'desc("mFGm-0")'
  M d
  R h
  $ hg status --copies --rev 'desc("g-1")' --rev 'desc("mGFm-0")'
  M d
  R h

  $ hg log -Gfr 'desc("mFGm-0")' d
  o    28 mFGm-0 simple merge - one way
  |\
  | o  25 g-1: update d
  | |
  o |  22 f-2: rename i -> d
  | |
  o |  21 f-1: rename h -> i
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h
  

  $ hg log -Gfr 'desc("mGFm-0")' d
  @    29 mGFm-0 simple merge - the other way
  |\
  | o  25 g-1: update d
  | |
  o |  22 f-2: rename i -> d
  | |
  o |  21 f-1: rename h -> i
  |/
  o  2 i-2: c -move-> d
  |
  o  1 i-1: a -move-> c
  |
  o  0 i-0 initial commit: a b h