[PATCH] submodule add: fix breakage when re-adding a deep submodule

[Jens Lehmann <Jens.Lehmann@web.de>]

Since recently a submodule with name <name> has its git directory in the
.git/modules/<name> directory of the superproject while the work tree
contains a gitfile pointing there.

When the same submodule is added on a branch where it wasn't present so
far (it is not found in the .gitmodules file), the name is not initialized
from the path as it should. This leads to a wrong path entered in the
gitfile when the .git/modules/<name> directory is found, as this happily
uses the - now empty - name. It then always points only a single directory
up, even if we have a path deeper in the directory hierarchy.

Fix that by initializing the name of the submodule early in module_clone()
if module_name() returned an empty name and add a test to catch that bug.

Reported-by: Jehan Bing <jehan@orb.com>
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
---

Am 24.01.2012 22:10, schrieb Jens Lehmann:
> Am 24.01.2012 20:11, schrieb Jehan Bing:
>> I'm getting an error if I try to add a module in a subdirectory and that module is already cloned.
>> Here are the steps to reproduce (git 1.7.8.3):

...

> The reason for this bug seems to be that in module_clonse() the name is
> not properly initialized for added submodules (it gets set to the path
> later), so the correct amount of leading "../"s for the git directory
> is not computed properly. The attached diff fixes that for me, I will
> send a patch as soon as I have extended a test case for this breakage.

Which I now have.


 git-submodule.sh            |    1 +
 t/t7406-submodule-update.sh |    8 ++++++++
 2 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/git-submodule.sh b/git-submodule.sh
index 3adab93..9bb2e13 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -131,6 +131,7 @@ module_clone()
 	gitdir=
 	gitdir_base=
 	name=$(module_name "$path" 2>/dev/null)
+	test -n "$name" || name="$path"
 	base_path=$(dirname "$path")

 	gitdir=$(git rev-parse --git-dir)
diff --git a/t/t7406-submodule-update.sh b/t/t7406-submodule-update.sh
index 33b292b..5b97222 100755
--- a/t/t7406-submodule-update.sh
+++ b/t/t7406-submodule-update.sh
@@ -611,4 +611,12 @@ test_expect_success 'submodule update places git-dir in superprojects git-dir re
 	)
 '

+test_expect_success 'submodule add properly re-creates deeper level submodules' '
+	(cd super &&
+	 git reset --hard master &&
+	 rm -rf deeper/ &&
+	 git submodule add ../submodule deeper/submodule
+	)
+'
+
 test_done
-- 
1.7.9.rc2.3.g18574a