git-clang-format clears files listed in .clang-format-ignore

[martinarendar]

When using git clang-format with .clang-format-ignore, the files listed in .clang-format-ignore are beeing cleared.

Example:
A simple main.cpp file located under [project root, location of .clang-format and .clang-format-ignore]/src/main.cpp:

#include <iostream>

int main() {
    std::cout << "Hello, World!" << std::endl;
    return 0;
}

If I add src/main.cpp to .clang-format-ignore and run git clang-format -f --style=file the contents of main.cpp get erased.
If I run clang-format -i --style=file src/main.cpp the file is ignored and everything works like it's supposed to.