rebase: turn rebaseskipobsolete on by default
Consider the following use case. User has a set of commits he wants to rebase
onto some destination. Some of the commits in the set are already rebased
and their new versions are now among the ancestors of destination. Traditional
rebase behavior would make the rebase and effectively try to apply older
versions of these commits on top of newer versions, like this:
a` --> b --> a`
(where both 'a`' and 'a``' are rebased versions of 'a')
This is not desired since 'b' might have made changes to 'a`' which can now
result in merge conflicts. We can avoid these merge conflicts since we know
that 'a``' is an older version of 'a`', so we don't even need to put it on top
of 'b'. Rebaseskipobsolete allows us to do exactly that.
Another undesired effect of a pure rebase is that now 'a`' and 'a``' are both
successors to 'a' which is a divergence. We don't want that and not rebasing
'a' the second time allows to avoid it.
This was not enabled by default initially because we wanted to have some more
experience with it. After months of painless usages in multiple places, we are
confident enough to turn it on my default.
$ HGMERGE=true; export HGMERGE
$ hg init r1
$ cd r1
$ echo a > a
$ hg addremove
adding a
$ hg commit -m "1"
$ hg clone . ../r2
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ../r2
$ hg up
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo abc > a
$ hg diff --nodates
diff -r c19d34741b0a a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-a
+abc
$ cd ../r1
$ echo b > b
$ echo a2 > a
$ hg addremove
adding b
$ hg commit -m "2"
$ cd ../r2
$ hg -q pull ../r1
$ hg status
M a
$ hg parents
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 1
$ hg --debug up
searching for copies back to rev 1
unmatched files in other:
b
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb
preserving a for resolve of a
b: remote created -> g
getting b
a: versions differ -> m (premerge)
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
a: versions differ -> m (merge)
picked tool 'true' for a (binary False symlink False changedelete False)
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg --debug up 0
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: 1e71731e6fbb, local: 1e71731e6fbb+, remote: c19d34741b0a
preserving a for resolve of a
b: other deleted -> r
removing b
starting 4 threads for background file closing (?)
a: versions differ -> m (premerge)
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb
a: versions differ -> m (merge)
picked tool 'true' for a (binary False symlink False changedelete False)
my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
0 files updated, 1 files merged, 1 files removed, 0 files unresolved
$ hg parents
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 1
$ hg parents
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 1
$ hg --debug up
searching for copies back to rev 1
unmatched files in other:
b
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb
preserving a for resolve of a
b: remote created -> g
getting b
a: versions differ -> m (premerge)
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
a: versions differ -> m (merge)
picked tool 'true' for a (binary False symlink False changedelete False)
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg -v history
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: a b
description:
2
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: a
description:
1
$ hg diff --nodates
diff -r 1e71731e6fbb a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-a2
+abc
create a second head
$ cd ../r1
$ hg up 0
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo b2 > b
$ echo a3 > a
$ hg addremove
adding b
$ hg commit -m "3"
created new head
$ cd ../r2
$ hg -q pull ../r1
$ hg status
M a
$ hg parents
changeset: 1:1e71731e6fbb
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg --debug up
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 other heads for branch "default"
test conflicting untracked files
$ hg up -qC 0
$ echo untracked > b
$ hg st
? b
$ hg up 1
b: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[255]
$ rm b
test conflicting untracked ignored file
$ hg up -qC 0
$ echo ignored > .hgignore
$ hg add .hgignore
$ hg ci -m 'add .hgignore'
created new head
$ echo ignored > ignored
$ hg add ignored
$ hg ci -m 'add ignored file'
$ hg up -q 'desc("add .hgignore")'
$ echo untracked > ignored
$ hg st
$ hg up 'desc("add ignored file")'
ignored: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[255]
test a local add
$ cd ..
$ hg init a
$ hg init b
$ echo a > a/a
$ echo a > b/a
$ hg --cwd a commit -A -m a
adding a
$ cd b
$ hg add a
$ hg pull -u ../a
pulling from ../a
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg st
$ cd ..