[PATCH] rebase: mark --update-refs as requiring the merge backend

["Elijah Newren via GitGitGadget" <gitgitgadget@gmail.com>]

From: Elijah Newren <newren@gmail.com>

--update-refs is built in terms of the sequencer, which requires the
merge backend.  It was already marked as incompatible with the apply
backend in the git-rebase manual, but the code didn't check for this
incompatibility and warn the user.  Check and warn now.

While at it, fix a typo in t3422...and fix some misleading wording (all
useful options other than --whitespace=fix have long since been
implemented in the merge backend).

Signed-off-by: Elijah Newren <newren@gmail.com>
---
    rebase: mark --update-refs as requiring the merge backend
    
    --update-refs is built in terms of the sequencer, which requires the
    merge backend. It was already marked as incompatible with the apply
    backend in the git-rebase manual, but the code didn't check for this
    incompatibility and warn the user. Check and warn now.
    
    While at it, fix a typo in t3422...and fix some misleading wording (all
    useful options other than --whitespace=fix have long since been
    implemented in the merge backend).
    
    Signed-off-by: Elijah Newren newren@gmail.com

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1466%2Fnewren%2Frebase-update-refs-imply-merge-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1466/newren/rebase-update-refs-imply-merge-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/1466

 builtin/rebase.c                       |  3 +++
 t/t3422-rebase-incompatible-options.sh | 15 ++++++++++-----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/builtin/rebase.c b/builtin/rebase.c
index 1481c5b6a5b..accd62fce48 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -1514,6 +1514,9 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 		}
 	}
 
+	if (options.update_refs)
+		imply_merge(&options, "--update-refs");
+
 	if (options.type == REBASE_UNSPECIFIED) {
 		if (!strcmp(options.default_backend, "merge"))
 			imply_merge(&options, "--merge");
diff --git a/t/t3422-rebase-incompatible-options.sh b/t/t3422-rebase-incompatible-options.sh
index 6dabb05a2ad..5a00618d265 100755
--- a/t/t3422-rebase-incompatible-options.sh
+++ b/t/t3422-rebase-incompatible-options.sh
@@ -25,11 +25,11 @@ test_expect_success 'setup' '
 '
 
 #
-# Rebase has lots of useful options like --whitepsace=fix, which are
-# actually all built in terms of flags to git-am.  Since neither
-# --merge nor --interactive (nor any options that imply those two) use
-# git-am, using them together will result in flags like --whitespace=fix
-# being ignored.  Make sure rebase warns the user and aborts instead.
+# Rebase has a useful option, --whitespace=fix, which is actually
+# built in terms of flags to git-am.  Since neither --merge nor
+# --interactive (nor any options that imply those two) use git-am,
+# using them together will result in --whitespace=fix being ignored.
+# Make sure rebase warns the user and aborts instead.
 #
 
 test_rebase_am_only () {
@@ -60,6 +60,11 @@ test_rebase_am_only () {
 		test_must_fail git rebase $opt --exec 'true' A
 	"
 
+	test_expect_success "$opt incompatible with --update-refs" "
+		git checkout B^0 &&
+		test_must_fail git rebase $opt --update-refs A
+	"
+
 }
 
 test_rebase_am_only --whitespace=fix

base-commit: 2b4f5a4e4bb102ac8d967cea653ed753b608193c
-- 
gitgitgadget