Merge branch 'ja/rebase-i-avoid-amending-self'

"git rebase -i" can mistakenly attempt to apply a fixup to a commit
itself, which has been corrected.

* ja/rebase-i-avoid-amending-self:
  sequencer: avoid dropping fixup commit that targets self via commit-ish

t/t3415-rebase-autosquash.sh

@@ -232,6 +232,19 @@ test_expect_success 'auto squash that matches longer sha1' '
 	test_line_count = 1 actual
 '
 
+test_expect_success 'auto squash of fixup commit that matches branch name which points back to fixup commit' '
+	git reset --hard base &&
+	git commit --allow-empty -m "fixup! self-cycle" &&
+	git branch self-cycle &&
+	GIT_SEQUENCE_EDITOR="cat >tmp" git rebase --autosquash -i HEAD^^ &&
+	sed -ne "/^[^#]/{s/[0-9a-f]\{7,\}/HASH/g;p;}" tmp >actual &&
+	cat <<-EOF >expect &&
+	pick HASH second commit
+	pick HASH fixup! self-cycle # empty
+	EOF
+	test_cmp expect actual
+'
+
 test_auto_commit_flags () {
 	git reset --hard base &&
 	echo 1 >file1 &&