[PATCH] rebase: use reflog to find common base with upstream

From

John Keeping <john@keeping.me.uk>

Date

Oct 16, 2013, 18:53 UTC

Message-ID

<d8e9f102609ee4502f579cb4ce872e0a40756204.1381949622.git.john@keeping.me.uk>

	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.

Change rebase so that it uses the same logic.

Signed-off-by: John Keeping <john@keeping.me.uk>
---
 git-rebase.sh     | 8 ++++++++
 t/t3400-rebase.sh | 6 ++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/git-rebase.sh b/git-rebase.sh
index 226752f..fd36cf7 100755
--- a/git-rebase.sh
+++ b/git-rebase.sh
@@ -437,6 +437,14 @@ then
 			error_on_missing_default_upstream "rebase" "rebase" \
 				"against" "git rebase <branch>"
 		fi
+		for reflog in $(git rev-list -g "$upstream_name" 2>/dev/null)
+		do
+			if test "$reflog" = "$(git merge-base "$reflog" HEAD)"
+			then
+				upstream_name=$reflog
+				break
+			fi
+		done
 		;;
 	*)	upstream_name="$1"
 		shift
diff --git a/t/t3400-rebase.sh b/t/t3400-rebase.sh
index ebf93b0..4f45f7e 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 merge-base topic master >expect &&
+	git rev-parse default~1 >actual &&
+	test_cmp expect actual
 '
 
 test_expect_success 'rebase -q is quiet' '

-- 
1.8.4.566.g73d370b