[PATCH v2] rebase: use reflog to find common base with upstream
- From
John Keeping <john@keeping.me.uk>
- Date
- Dec 9, 2013, 23:16 UTC
- Message-ID
- <20131209231616.GG3163@serenity.lan>
- In-Reply-To
- <20131209204008.GF3163@serenity.lan>
Commit 15a147e (rebase: use @{upstream} if no upstream specified, 2011-02-09) says:
Make it default to 'git rebase @{upstream}'. That is also what
'git pull [--rebase]' defaults to, so it only makes sense that
'git rebase' defaults to the same thing.but that isn't actually the case. Since commit d44e712 (pull: support rebased upstream + fetch + pull --rebase, 2009-07-19), pull has actually chosen the most recent reflog entry which is an ancestor of the current branch if it can find one.
Add a '--fork-point' argument to git-rebase that can be used to trigger this behaviour. This option is turned on by default if no non-option arguments are specified on the command line, otherwise we treat an upstream specified on the command-line literally.
Signed-off-by: John Keeping <john@keeping.me.uk> --- On Mon, Dec 09, 2013 at 08:40:08PM +0000, John Keeping wrote:
Show 23 quoted lines
> On Mon, Dec 09, 2013 at 12:11:50PM -0800, Junio C Hamano wrote:
> > Do you mean
> >
> > git rebase <no other arguments>
> >
> > which we interpret as "rebase the current branch on @{u}", and it
> > should behave as if the command was run like so:
> >
> > git rebase --fork-point @{u}
> >
> > If that is what you suggest, I certainly can buy that. Those who
> > want to disable the automation can explicitly say
> >
> > git rebase @{u}
> >
> > and rebase the current exactly on top of the named commit (e.g. the
> > current value of refs/remotes/origin/master or whatever remote-tracking
> > branch you forked from).
>
> Yes, that's what I meant; the first non-option argument to "git rebase"
> is called "upstream" in the manpage (and throughout the code). So if
> "<no other arguments>" means "<no non-option arguments>" then that's
> exactly what I meant.Here's an updated patch that adds a --fork-point option to git-rebase, with the behaviour described above.
Documentation/git-rebase.txt | 10 ++++++++++ git-rebase.sh | 19 +++++++++++++++++++ t/t3400-rebase.sh | 6 ++++-- 3 files changed, 33 insertions(+), 2 deletions(-)
diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt index 94e07fd..2889be6 100644 --- a/Documentation/git-rebase.txt +++ b/Documentation/git-rebase.txt @@ -324,6 +324,16 @@ fresh commits so it can be remerged successfully without needing to "revert the reversion" (see the link:howto/revert-a-faulty-merge.html[revert-a-faulty-merge How-To] for details). +--fork-point:: +--no-fork-point:: + Use 'git merge-base --fork-point' to find a better common ancestor + between `upstream` and `branch` when calculating which commits have + have been introduced by `branch` (see linkgit:git-merge-base[1]). ++ +If no non-option arguments are given on the command line, then the default is +`--fork-point @{u}` otherwise the `upstream` argument is interpreted literally +unless the `--fork-point` option is specified. + --ignore-whitespace:: --whitespace=<option>:: These flag are passed to the 'git apply' program diff --git a/git-rebase.sh b/git-rebase.sh index 226752f..7185dc8 100755 --- a/git-rebase.sh +++ b/git-rebase.sh @@ -14,6 +14,7 @@ git-rebase --continue | --abort | --skip | --edit-todo v,verbose! display a diffstat of what changed upstream q,quiet! be quiet. implies --no-stat autostash! automatically stash/stash pop before and after +fork-point use 'merge-base --fork-point' to refine upstream onto=! rebase onto given branch instead of upstream p,preserve-merges! try to recreate merges instead of ignoring them s,strategy=! use the given merge strategy @@ -66,6 +67,7 @@ verbose= diffstat= test "$(git config --bool rebase.stat)" = true && diffstat=t autostash="$(git config --bool rebase.autostash || echo false)" +fork_point=auto git_am_opt= rebase_root= force_rebase= @@ -260,6 +262,12 @@ do --no-autosquash) autosquash= ;; + --fork-point) + fork_point=t + ;; + --no-fork-point) + fork_point= + ;; -M|-m) do_merge=t ;; @@ -437,6 +445,8 @@ then error_on_missing_default_upstream "rebase" "rebase" \ "against" "git rebase <branch>" fi + + test "$fork_point" = auto && fork_point=t ;; *) upstream_name="$1" shift @@ -522,6 +532,15 @@ case "$#" in ;; esac +if test "$fork_point" = t +then + new_upstream=$(git merge-base --fork-point "$upstream_name" "$switch_to") + if test -n "$new_upstream" + then + upstream=$new_upstream + fi +fi + if test "$autostash" = true && ! (require_clean_work_tree) 2>/dev/null then stash_sha1=$(git stash create "autostash") || diff --git a/t/t3400-rebase.sh b/t/t3400-rebase.sh index ebf93b0..998503d 100755 --- a/t/t3400-rebase.sh +++ b/t/t3400-rebase.sh @@ -134,12 +134,14 @@ test_expect_success 'fail when upstream arg is missing and not configured' ' test_must_fail git rebase ' -test_expect_success 'default to @{upstream} when upstream arg is missing' ' +test_expect_success 'default to common base in @{upstream}s reflog if no upstream arg' ' git checkout -b default topic && git config branch.default.remote . && git config branch.default.merge refs/heads/master && git rebase && - test "$(git rev-parse default~1)" = "$(git rev-parse master)" + git rev-parse --verify master >expect && + git rev-parse default~1 >actual && + test_cmp expect actual ' test_expect_success 'rebase -q is quiet' '
-- 1.8.5.226.g0d60d77