shell get script abs path

vmuser@vmuser-virtual-machine:~/panzidong/shell$ cat tmp.sh
#!/bin/bash
echo "$(dirname "$(realpath "${BASH_SOURCE}")")"
echo "$(realpath "${BASH_SOURCE}")"
echo "${BASH_SOURCE}"

vmuser@vmuser-virtual-machine:~/panzidong/shell$ ./tmp.sh
/home/vmuser/panzidong/shell
/home/vmuser/panzidong/shell/tmp.sh
./tmp.sh