From 41c64ae0e762d2c4ef1ddd578b8992967547dc5f Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Thu, 21 Apr 2022 14:25:47 -0700 Subject: [PATCH] show-branch: -g and --current are incompatible When "--current" is given to "git show-branch" running in the "--reflog" mode, the code tries to reference a "reflog" message that does not even exist. This is because the --current is not prepared to work in that mode. The reason "--current" exists is to support this request: I list branches on the command line. These are the branchesI care about and I use as anchoring points. I may or may not be on one of these main branches. Please make sure I can view the commits on the current branch with respect to what is in these other branches. And to serve that request, the code checks if the current branch is among the ones listed on the command line, and adds it only if it is not to the end of one array, which essentially lists the objects. The reflog mode additionally uses another array to list reflog messages, which the "--current" code does not add to. This leaves one uninitialized slot at the end of the array of reflog messages, and causes the program to show garbage or segfault. Catch the unsupported (and meaningless) combination and exit with a usage error. There are other combinations of options that are incompatible but have not been tested. Add test to cover them while adding coverage for this new combination. Reported-by: Gregory David Signed-off-by: Junio C Hamano --- builtin/show-branch.c | 4 ++++ t/t3202-show-branch.sh | 14 ++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/builtin/show-branch.c b/builtin/show-branch.c index e12c5e80e3..73e8edbf02 100644 --- a/builtin/show-branch.c +++ b/builtin/show-branch.c @@ -711,6 +711,10 @@ int cmd_show_branch(int ac, const char **av, const char *prefix) "--all/--remotes/--independent/--merge-base"); } + if (with_current_branch && reflog) + die(_("options '%s' and '%s' cannot be used together"), + "--reflog", "--current"); + /* If nothing is specified, show all branches by default */ if (ac <= topics && all_heads + all_remotes == 0) all_heads = 1; diff --git a/t/t3202-show-branch.sh b/t/t3202-show-branch.sh index 7a1be73ce8..f2b9199007 100755 --- a/t/t3202-show-branch.sh +++ b/t/t3202-show-branch.sh @@ -161,4 +161,18 @@ test_expect_success 'show branch --reflog=2' ' test_cmp actual expect ' +# incompatible options +while read combo +do + test_expect_success "show-branch $combo (should fail)" ' + test_must_fail git show-branch $combo 2>error && + grep -e "cannot be used together" -e "usage:" error + ' +done <<\EOF +--all --reflog +--merge-base --reflog +--list --merge-base +--reflog --current +EOF + test_done