evolve: handle relocation during divergence resolution producing no changes
When resolving divergence and the two divergent commits have different
parents, we start by rebasing one of them to have the same parent as
the other. That step can result in no changes to commit. When it does,
we would crash with a TypeError before this patch.
This patch fixes it by instead creating an empty commit in that
scenario. The existing code then continues to attempt to merge it,
which produces no changes, and no commit is created on top. The other
side of the divergence is marked as successor as usual, so orphans
from the side that became empty will be evolved to the right place
(see test).
====================================
Testing head checking code: Case D-4
====================================
Mercurial checks for the introduction of new heads on push. Evolution comes
into play to detect if existing branches on the server are being replaced by
some of the new one we push.
This case is part of a series of tests checking this behavior.
Category D: remote head is "obs-affected" locally, but result is not part of the push
TestCase 4: multi-changeset branch, split on multiple other, (base on its own new branch)
.. old-state:
..
.. * 2 branch (1 changeset, and 2 changesets)
..
.. new-state:
..
.. * 1 new branch superceeding the base of the old-2-changesets-branch,
.. * 1 new changesets on the old-1-changeset-branch superceeding the head of the other
..
.. expected-result:
..
.. * push the new branch only -> push denied (variant a)
.. * push the existing branch only -> push allowed (variant b)
.. (pushing all is tested as case A-7)
..
.. graph-summary:
..
.. (variant a)
..
.. B'○⇢ø B
.. | |
.. A | ø⇠◔ A'
.. | |/
.. C ● |
.. \|
.. ●
..
.. or (variant b)
..
.. B'◔⇢ø B
.. | |
.. A | ø⇠○ A'
.. | |/
.. C ● |
.. \|
.. ●
$ . $TESTDIR/testlib/push-checkheads-util.sh
Test setup
----------
$ mkdir D4
$ cd D4
$ setuprepos
creating basic server and client repo
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd server
$ mkcommit B0
$ hg up 0
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ mkcommit C0
created new head
$ cd ../client
$ hg pull
pulling from $TESTTMP/D4/server (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files (+1 heads)
new changesets d73caddc5533:0f88766e02d6 (2 drafts)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkcommit A1
created new head
$ hg up 'desc(C0)'
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkcommit B1
$ hg debugobsolete `getid "desc(A0)" ` `getid "desc(A1)"`
1 new obsolescence markers
obsoleted 1 changesets
1 new orphan changesets
$ hg debugobsolete `getid "desc(B0)" ` `getid "desc(B1)"`
1 new obsolescence markers
obsoleted 1 changesets
$ hg log -G --hidden
@ d70a1f75a020 (draft): B1
|
| o f6082bc4ffef (draft): A1
| |
o | 0f88766e02d6 (draft): C0
|/
| x d73caddc5533 (draft): B0
| |
| x 8aaa48160adc (draft): A0
|/
o 1e4be0697311 (public): root
Actual testing (new branch only)
--------------------------------
$ hg push --rev 'desc(A1)'
pushing to $TESTTMP/D4/server (glob)
searching for changes
abort: push creates new remote head f6082bc4ffef!
(merge or see 'hg help push' for details about pushing new heads)
[255]
Actual testing (existing branch only)
------------------------------------
$ hg push --rev 'desc(B1)'
pushing to $TESTTMP/D4/server (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
1 new obsolescence markers
obsoleted 1 changesets
$ cd ../..