submodule: rewrite `module_list` shell function in C

diff --git a/contrib/subtree/t/t7900-subtree.sh b/contrib/subtree/t/t7900-subtree.sh
index 001c604dd1093ea678ef4e183a6184f3c3dad2b1..90519823be381390b7f89a1eb2f6007f1e8c86f4 100755 (executable)
--- a/contrib/subtree/t/t7900-subtree.sh
+++ b/contrib/subtree/t/t7900-subtree.sh
@@ -94,6 +94,10 @@ test_expect_success 'add sub3' '
 # Back to mainline
 cd ..
 
+test_expect_success 'enable log.date=relative to catch errors' '
+       git config log.date relative
+'
+
 test_expect_success 'add main4' '
        create main4 &&
        git commit -m "main4" &&
@@ -221,9 +225,7 @@ test_expect_success 'check hash of split' '
        spl1=$(git subtree split --prefix subdir) &&
        git subtree split --prefix subdir --branch splitbr1test &&
        check_equal ''"$(git rev-parse splitbr1test)"'' "$spl1" &&
-       git checkout splitbr1test &&
-       new_hash=$(git rev-parse HEAD~2) &&
-       git checkout mainline &&
+       new_hash=$(git rev-parse splitbr1test~2) &&
        check_equal ''"$new_hash"'' "$subdir_hash"
 '