From 8338f771fe9720766dfcb25b6dca58832e24a0fd Mon Sep 17 00:00:00 2001 From: Erik Faye-Lund Date: Tue, 8 May 2012 19:22:33 +0200 Subject: [PATCH] checkout: do not corrupt HEAD on empty repo In abe1998 ("git checkout -b: allow switching out of an unborn branch"), a code-path overly-optimisticly assumed that a branch-name was specified. This is not always the case, and as a result a NULL-pointer was attempted printed to .git/HEAD. This could lead to at least two different failure modes: 1) vsnprintf formated the NULL-string as something useful (e.g "(null)") 2) vsnprintf crashed Neither were very convenient for formatting a new HEAD-reference. To fix this, reintroduce some strictness so we only take this new codepath if a banch-name was specified. Signed-off-by: Erik Faye-Lund Signed-off-by: Junio C Hamano --- builtin/checkout.c | 2 +- t/t2015-checkout-unborn.sh | 11 +++++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/builtin/checkout.c b/builtin/checkout.c index b76e2c045..44ecc22e5 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -1100,7 +1100,7 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) if (opts.writeout_stage) die(_("--ours/--theirs is incompatible with switching branches.")); - if (!new.commit) { + if (!new.commit && opts.new_branch) { unsigned char rev[20]; int flag; diff --git a/t/t2015-checkout-unborn.sh b/t/t2015-checkout-unborn.sh index 6352b74e2..37bdcedcc 100755 --- a/t/t2015-checkout-unborn.sh +++ b/t/t2015-checkout-unborn.sh @@ -46,4 +46,15 @@ test_expect_success 'checking out another branch from unborn state' ' test_cmp expect actual ' +test_expect_success 'checking out in a newly created repo' ' + test_create_repo empty && + ( + cd empty && + git symbolic-ref HEAD >expect && + test_must_fail git checkout && + git symbolic-ref HEAD >actual && + test_cmp expect actual + ) +' + test_done -- 2.26.2