t4045: abstract away SHA-1-specific constants

diff --git a/t/t4150-am.sh b/t/t4150-am.sh
index 1eccfb71d0c8e26f88708459f065dea622baf9d3..1ebc587f8fc0010713f52196206462fa915cbca5 100755 (executable)
--- a/t/t4150-am.sh
+++ b/t/t4150-am.sh
@@ -140,8 +140,8 @@ test_expect_success setup '
                echo "# User $GIT_AUTHOR_NAME <$GIT_AUTHOR_EMAIL>" &&
                echo "# Date $test_tick 25200" &&
                echo "#      $(git show --pretty="%aD" -s second)" &&
-               echo "# Node ID $_z40" &&
-               echo "# Parent  $_z40" &&
+               echo "# Node ID $ZERO_OID" &&
+               echo "# Parent  $ZERO_OID" &&
                cat msg &&
                echo &&
                git diff-tree --no-commit-id -p second