checkout: improve error messages for -b with extra argument

When we try to create a branch "foo" based on "origin/master" and give
git commit -b an extra unsupported argument "bar", it confusingly
reports:

   $ git checkout -b foo origin/master bar
   fatal: 'bar' is not a commit and a branch 'foo' cannot be created from it

   $ git checkout --track -b foo origin/master bar
   fatal: 'bar' is not a commit and a branch 'foo' cannot be created from it

That's wrong, because it very well understands that "origin/master" is
supposed to be the start point for the new branch and not "bar".  Check
if we got a commit and show more fitting messages in that case instead:

   $ git checkout -b foo origin/master bar
   fatal: Cannot update paths and switch to branch 'foo' at the same time.

   $ git checkout --track -b foo origin/master bar
   fatal: '--track' cannot be used with updating paths

Original-patch-by: Jeff King <peff@peff.net>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/checkout.c b/builtin/checkout.c
index e9d111bb8360d19c4c81fa6d8caa54b8049576fe..24336e10173362e5001b5091ba95422c6e52b167 100644 (file)
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -1689,7 +1689,7 @@ static int checkout_main(int argc, const char **argv, const char *prefix,
                 * Try to give more helpful suggestion.
                 * new_branch && argc > 1 will be caught later.
                 */
-               if (opts->new_branch && argc == 1)
+               if (opts->new_branch && argc == 1 && !new_branch_info.commit)
                        die(_("'%s' is not a commit and a branch '%s' cannot be created from it"),
                                argv[0], opts->new_branch);
 

diff --git a/t/t2018-checkout-branch.sh b/t/t2018-checkout-branch.sh
index b166cb302f94f685561763dbe2efda89e9ec115b..5f761bc616ee5871055d6beed29e768b328f6827 100755 (executable)
--- a/t/t2018-checkout-branch.sh
+++ b/t/t2018-checkout-branch.sh
@@ -265,7 +265,7 @@ test_expect_success 'checkout -b rejects an invalid start point' '
        test_i18ngrep "is not a commit" err
 '
 
-test_expect_failure 'checkout -b rejects an extra path argument' '
+test_expect_success 'checkout -b rejects an extra path argument' '
        test_must_fail git checkout -b branch5 branch1 file1 2>err &&
        test_i18ngrep "Cannot update paths and switch to branch" err
 '

diff --git a/t/t2027-checkout-track.sh b/t/t2027-checkout-track.sh
index d0b41d7cd08ccc31c7163e517c50b5fc3395a176..bcba1bf90c090a00e7e734aac4cb5a2d55ed1f66 100755 (executable)
--- a/t/t2027-checkout-track.sh
+++ b/t/t2027-checkout-track.sh
@@ -16,7 +16,7 @@ test_expect_success 'checkout --track -b creates a new tracking branch' '
        test $(git config --get branch.branch1.merge) = refs/heads/master
 '
 
-test_expect_failure 'checkout --track -b rejects an extra path argument' '
+test_expect_success 'checkout --track -b rejects an extra path argument' '
        test_must_fail git checkout --track -b branch2 master one.t 2>err &&
        test_i18ngrep "cannot be used with updating paths" err
 '