.mbedignore not works fully

i have folder /file structure like that:
- Mbed
- main.cpp
- lib
- inih
- INIReaderTest.cpp

main.cpp is my main file containing method main
and Inih downloaded from https://github.com/jtilly/inih contains a file INIReaderTest.cpp with another main method.
Thus i need an .mbedignore.
If i place it in folder Mbed, it does not work, whereas in folder lib it does work.

Compliation is done with `mbed compile --source . --source mbed-os --source lib`

i use mbed version 1.10.2 with python 3.8.2 on linux