git cherry-pick --keep-redundant-commits HEAD^
'
+test_expect_success 'cherry-pick a commit that becomes no-op (prep)' '
+ git checkout master &&
+ git branch fork &&
+ echo foo >file2 &&
+ git add file2 &&
+ test_tick &&
+ git commit -m "add file2 on master" &&
+
+ git checkout fork &&
+ echo foo >file2 &&
+ git add file2 &&
+ test_tick &&
+ git commit -m "add file2 on the side"
+'
+
+test_expect_success 'cherry-pick a no-op without --keep-redundant' '
+ git reset --hard &&
+ git checkout fork^0 &&
+ test_must_fail git cherry-pick master
+'
+
+test_expect_success 'cherry-pick a no-op with --keep-redundant' '
+ git reset --hard &&
+ git checkout fork^0 &&
+ git cherry-pick --keep-redundant-commits master &&
+ git show -s --format='%s' >actual &&
+ echo "add file2 on master" >expect &&
+ test_cmp expect actual
+'
+
test_done