Prior to c85c792 (pull --rebase: be cleverer with rebased upstream
branches, 2008-01-26), pull --rebase would run
git rebase $merge_head
which resulted in a call to
git format-patch ... --ignore-if-in-upstream $merge_head..$cur_branch
This resulted in patches from $merge_head..$cur_branch being applied, as
long as they did not already exist in $cur_branch..$merge_head.
Unfortunately, when upstream is rebased, $merge_head..$cur_branch also
refers to "old" commits that have already been rebased upstream, meaning
that many patches that were already fixed upstream would be reapplied.
This could result in many spurious conflicts, as well as reintroduce
patches that were intentionally dropped upstream.
So the algorithm was changed in c85c792 (pull --rebase: be cleverer with
rebased upstream branches, 2008-01-26) and d44e712 (pull: support rebased
upstream + fetch + pull --rebase, 2009-07-19). Defining $old_remote_ref to
be the most recent entry in the reflog for @{upstream} that is an ancestor
of $cur_branch, pull --rebase was changed to run
git rebase --onto $merge_head $old_remote_ref
which results in a call to
git format-patch ... --ignore-if-in-upstream $old_remote_ref..$cur_branch
The whole point of this change was to reduce the number of commits being
reapplied, by avoiding commits that upstream already has or had.
In the rebased upstream case, this change achieved that purpose. It is
worth noting, though, that since $old_remote_ref is always an ancestor of
$cur_branch (by its definition), format-patch will not know what upstream
is and thus will not be able to determine if any patches are already
upstream; they will all be reapplied.
In the non-rebased upstream case, this new form is usually the same as the
original code but in some cases $old_remote_ref can be an ancestor of
$(git merge-base $merge_head $cur_branch)
meaning that instead of avoiding reapplying commits that upstream already
has, it actually includes more such commits. Combined with the fact that
format-patch can no longer detect commits that are already upstream (since
it is no longer told what upstream is), results in lots of confusion for
users (e.g. "git is giving me lots of conflicts in stuff I didn't even
change since my last push.")
Cases where additional commits could be reapplied include forking from a
commit other than the tracking branch, or amending/rebasing after pushing.
Cases where the inability to detect upstreamed commits cause problems
include independent discovery of a fix and having your patches get
upstreamed by some alternative route (e.g. pulling your changes to a third
machine, pushing from there, and then going back to your original machine
and trying to pull --rebase).
Fix the non-rebased upstream case by ignoring $old_remote_ref whenever it
is contained in $(git merge-base $merge_head $cur_branch). This should
have no affect on the rebased upstream case.
Acked-by: Santi Béjar <santi@agolina.net>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In tests, call test_cmp rather than raw diff where possible (i.e. if
the output does not go to a pipe), to allow the use of, say, 'cmp'
when the default 'diff -u' is not compatible with a vendor diff.
When that is not possible, use $DIFF, as set in GIT-BUILD-OPTIONS.
Signed-off-by: Gary V. Vaughan <gary@thewrittenword.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When doing a "pull --rebase", we check to make sure that the index and
working tree are clean. The index-clean check compares the index against
HEAD. The test erroneously reports dirtiness if we don't have a HEAD yet.
In such an "unborn branch" case, by definition, a non-empty index won't
be based on whatever we are pulling down from the remote, and will lose
the local change. Just check if $GIT_DIR/index exists and error out.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
You cannot do a "git pull --rebase" with a rebased upstream, if you have
already run "git fetch". Try to behave as if the "git fetch" was not run.
In other words, find the fork point of the current branch, where
the tip of upstream branch used to be, and use it as the upstream
parameter of "git rebase".
This patch computes the fork point by walking the reflog to find the first
commit which is an ancestor of the current branch. Maybe there are
smarter ways to compute it, but this is a straight forward implementation.
Signed-off-by: Santi Béjar <santi@agolina.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If your upstream has rebased you can do:
git pull --rebase
but only if you haven't fetch before.
Mark this case as test_expect_failure, in a later patch it will be
changed to test_expect_success.
Signed-off-by: Santi Béjar <santi@agolina.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Expand get_remote_merge_branch to compute the tracking branch to merge
when called without arguments (or only the remote name). This allows
"git pull --rebase" without arguments (default upstream branch) to
work with a rebased upstream. With explicit arguments it already worked.
Also add a test to check for this case.
Signed-off-by: Santi Béjar <santi@agolina.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some misguided documents floating on the Net suggest this sequence:
mkdir newdir && cd newdir
git init
git remote add origin $url
git pull origin master:master
"git pull" has known about misguided "pull" that lets the underlying fetch
update the current branch for a long time. It also has known about
"git pull origin master" into a branch yet to be born.
These two workarounds however were not aware of the existence of each
other and did not work well together. This fixes it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When rebasing fails during "pull --rebase", you cannot just clean up the
working directory and call "pull --rebase" again, since the remote branch
was already fetched.
Therefore, die early when the working directory is dirty.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the upstream branch is tracked, we can detect if that branch
was rebased since it was last fetched. Teach git to use that
information to rebase from the old remote head onto the new remote head.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When calling 'git pull' with the '--rebase' option, it performs a
fetch + rebase instead of a fetch + merge.
This behavior is more desirable than fetch + pull when a topic branch
is ready to be submitted and needs to be update.
fetch + rebase might also be considered a better workflow with shared
repositories in any case, or for contributors to a centrally managed
repository, such as WINE's.
As a convenience, you can set the default behavior for a branch by
defining the config variable branch.<name>.rebase, which is
interpreted as a bool. This setting can be overridden on the command
line by --rebase and --no-rebase.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This uses "git-apply --whitespace=strip" to fix whitespace errors that have
crept in to our source files over time. There are a few files that need
to have trailing whitespaces (most notably, test vectors). The results
still passes the test, and build result in Documentation/ area is unchanged.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch adds support for a dummy remote '.' to avoid having
to declare a fake remote like
[remote "local"]
url = .
fetch = refs/heads/*:refs/heads/*
Such a builtin remote simplifies the operation of "git-fetch",
which will populate FETCH_HEAD but will not pretend that two
repositories are in use, will not create a thin pack, and will
not perform any useless remapping of names. The speed
improvement is around 20%, and it should improve more if
"git-fetch" is converted to a builtin.
To this end, git-parse-remote is grown with a new kind of
remote, 'builtin'. In git-fetch.sh, we treat the builtin remote
specially in that it needs no pack/store operations. In fact,
doing git-fetch on a builtin remote will simply populate
FETCH_HEAD appropriately.
The patch also improves of the --track/--no-track support,
extending it so that branch.<name>.remote items referring '.'
can be created. Finally, it fixes a typo in git-checkout.sh.
Signed-off-by: Paolo Bonzini <bonzini@gnu.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
While 'init-db' still is and probably will always remain a valid git
command for obvious backward compatibility reasons, it would be a good
idea to move shipped tools and docs to using 'init' instead.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
We used to complain that we cannot merge anything we fetched
with a local branch that does not exist yet. Just treat the
case as a natural extension of fast forwarding and make the
local branch'es tip point at the same commit we just fetched.
After all an empty repository without an initial commit is an
ancestor of any commit.
[jc: I added a trivial test. We've become sloppy but we should
stick to the discipline of covering new behaviour with new
tests. ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
