[PATCH 7/7] rebase (without -p): correctly calculate patches to rebase
The different types of rebase use different ways of calculating the patches to rebase.
'git rebase' (without -m/-i/-p) uses
git format-patch --ignore-if-in-upstream $upstream..$orig_head
'git rebase -m' uses
git rev-list $upstream..$orig_head
'git rebase -i' (without -p) uses
git rev-list $upstream...$orig_head --left-right --no-merges \
--cherry-pick | sed -n "s/^>//p", which could also have been written
git rev-list $upstream...$orig_head --right-only --no-merges \
--cherry-pick'git rebase -p' uses
git rev-list $upstream...$orig_head --right-only
followed by cherry-picked commits found by
git rev-list $upstream...$orig_head --cherry-mark --right-only |
| sed -ne "s/^=//p"
As Knut Franke reported in [1], the fact that there is no --ignore-if-in-upstream or equivalent when using merge-based rebase means that unnecessary conflicts can arise due to commits cherry-picked between $orig_head and $upstream.
With all the other types, there is a different problem with the method of calculating the commits to rebase. Copying the example history from [1]:
.-c
/
a---b---d---e---f
\
.-g---ECommit E is here a cherry-pick of e. If we now run 'git rebase [-i|-p] --onto c f E', the commits to rebase will be those on E that are not equivalent to any of those in f, which in this case would be only 'g'. Commit 'E' would thus be lost.
To solve both of the above problems, we want to find the commits in $upstream..$orig_head that are not cherry-picked in $orig_head..$onto. There is unfortunately no direct way of finding these commits using 'git rev-list', so we will have to resort to using 'git cherry' and filter for lines starting with '+'. This works for all but 'rebase -p', since 'git cherry' ignores merges.
As a side-effect, we also avoid the cost of formatting patches.
Test case updates for 'rebase -m' by Knut, the rest by Martin.
[1] http://thread.gmane.org/gmane.comp.version-control.git/161917
Helped-by: Knut Franke <Knut.Franke@gmx.de>
Signed-off-by: Martin von Zweigbergk <martin.von.zweigbergk@gmail.com>
---
git-rebase--am.sh | 6 ++----
git-rebase--interactive.sh | 8 +++-----
git-rebase--merge.sh | 2 +-
git-rebase.sh | 11 ++++-------
t/t3401-rebase-partial.sh | 17 +++++++++++++++++
t/t3406-rebase-message.sh | 14 +++++++-------
6 files changed, 34 insertions(+), 24 deletions(-)
Show changes to 6 files +34 −24
git-rebase--am.sh, git-rebase--interactive.sh, git-rebase--merge.sh, git-rebase.sh, t/t3401-rebase-partial.sh, t/t3406-rebase-message.sh
diff --git a/git-rebase--am.sh b/git-rebase--am.sh
index 37c1b23..fe3fdd1 100644
--- a/git-rebase--am.sh
+++ b/git-rebase--am.sh
@@ -16,11 +16,9 @@ skip)
;;
esac
-test -n "$rebase_root" && root_flag=--root
test -n "$keep_empty" && git_am_opt="$git_am_opt --keep-empty"
-git format-patch -k --stdout --full-index --ignore-if-in-upstream \
- --src-prefix=a/ --dst-prefix=b/ \
- --no-renames $root_flag "$revisions" |
+generate_revisions |
+sed -e 's/\([0-9a-f]\{40\}\)/From \1 Mon Sep 17 00:00:00 2001/' |
git am $git_am_opt --rebasing --resolvemsg="$resolvemsg" &&
move_to_original_branch
diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index cd5a2cc..da32ca7 100644
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -800,10 +800,8 @@ if test -z "$rebase_root"
# this is now equivalent to ! -z "$upstream"
then
shortupstream=$(git rev-parse --short $upstream)
- revisions=$upstream...$orig_head
shortrevisions=$shortupstream..$shorthead
else
- revisions=$onto...$orig_head
shortrevisions=$shorthead
fi
@@ -822,6 +820,7 @@ if test t = "$preserve_merges"
then
if test -z "$rebase_root"
then
+ revisions=$upstream...$orig_head
mkdir "$rewritten" &&
for c in $(git merge-base --all $orig_head $upstream)
do
@@ -829,6 +828,7 @@ then
die "Could not init rewritten commits"
done
else
+ revisions=$onto...$orig_head
mkdir "$rewritten" &&
echo $onto > "$rewritten"/root ||
die "Could not init rewritten commits"
@@ -876,9 +876,7 @@ then
fi
done
else
- git rev-list $revisions --reverse --left-right --topo-order \
- --no-merges --cherry-pick |
- sed -n "s/^>//p" |
+ generate_revisions |
while read -r sha1
do
add_pick_line $sha1
diff --git a/git-rebase--merge.sh b/git-rebase--merge.sh
index b10f2cf..bf4ec4b 100644
--- a/git-rebase--merge.sh
+++ b/git-rebase--merge.sh
@@ -131,7 +131,7 @@ echo "$onto_name" > "$state_dir/onto_name"
write_basic_state
msgnum=0
-for cmt in `git rev-list --reverse --no-merges "$revisions"`
+for cmt in $(generate_revisions)
do
msgnum=$(($msgnum + 1))
echo "$cmt" > "$state_dir/cmt.$msgnum"
diff --git a/git-rebase.sh b/git-rebase.sh
index 1cd0633..0fdff87 100755
--- a/git-rebase.sh
+++ b/git-rebase.sh
@@ -530,6 +530,10 @@ then
GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
fi
+generate_revisions () {
+ git cherry $onto $orig_head $upstream | sed -ne 's/^+ //p'
+}
+
test "$type" = interactive && run_specific_rebase
# Detach HEAD and reset the tree
@@ -546,11 +550,4 @@ then
exit 0
fi
-if test -n "$rebase_root"
-then
- revisions="$onto..$orig_head"
-else
- revisions="$upstream..$orig_head"
-fi
-
run_specific_rebase
diff --git a/t/t3401-rebase-partial.sh b/t/t3401-rebase-partial.sh
index 7f8693b..9c5d815 100755
--- a/t/t3401-rebase-partial.sh
+++ b/t/t3401-rebase-partial.sh
@@ -50,4 +50,21 @@ test_expect_success 'rebase ignores empty commit' '
test $(git log --format=%s C..) = "D"
'
+test_expect_success 'rebase --onto does not re-apply patches in $onto' '
+ git checkout C &&
+ test_commit C2 C.t &&
+ git checkout -B my-topic-branch master &&
+ test_commit E &&
+ git rebase --onto C2 A2 &&
+ test "$(git log --format=%s C2..)" = E
+'
+
+test_expect_success 'rebase --onto does not lose patches in $upstream' '
+ git rebase --onto A2 E &&
+ test "$(git log --format=%s A2..)" = "E
+C2
+C
+B"
+'
+
test_done
diff --git a/t/t3406-rebase-message.sh b/t/t3406-rebase-message.sh
index 6898377..3eecc66 100755
--- a/t/t3406-rebase-message.sh
+++ b/t/t3406-rebase-message.sh
@@ -5,8 +5,10 @@ test_description='messages from rebase operation'
. ./test-lib.sh
quick_one () {
- echo "$1" >"file$1" &&
- git add "file$1" &&
+ fileno=$2
+ test -z "$fileno" && fileno=$1
+ echo "$1" >"file$fileno" &&
+ git add "file$fileno" &&
test_tick &&
git commit -m "$1"
}
@@ -16,21 +18,19 @@ test_expect_success setup '
git branch topic &&
quick_one X &&
quick_one A &&
- quick_one B &&
+ quick_one B A &&
quick_one Y &&
git checkout topic &&
quick_one A &&
- quick_one B &&
+ quick_one B A &&
quick_one Z &&
git tag start
'
cat >expect <<\EOF
-Already applied: 0001 A
-Already applied: 0002 B
-Committed: 0003 Z
+Committed: 0001 Z
EOF
test_expect_success 'rebase -m' '
--
1.7.11.1.104.ge7b44f1
Martin von Zweigbergk
