Question about fw_ testcase

[charlotte-smi]

Hi,
I noticed that most testcases under test_suites include readable source files such as .c or .s.
However, some testcases with the fw_ prefix (e.g. fw_test_lms_n24_w1_h15) only contain files without extensions.
When I opened it looks like the screenshot below and I cannot find the corresponding source code.

Could you clarify:

• Where the original source code is located

• Whether there is a recommended way to inspect or understand the testcase behavior

Thanks for the help.