"unknown shell type" error when "source diracos env" in bash scripts

[zhangxiaomei]

In an executable script (test.sh) with "source DIRAC OS environment":
#!/bin/bash
source /cvmfs/dcomputing.ihep.ac.cn/dirac/IHEPDIRAC/v3r1/diracos/diracosrc

I got the error like the following:
(base) -bash-4.2$ ./test.sh
error libmamba Please provide a shell type.
Run with --help for more information.

critical libmamba Unknown shell type. Aborting.

How to avoid this error?

[andresailer]

This has already been reported #7260