The only tool I can find so far is https://github.com/github/linguist
I am sure this tool works fine in some situations. I get a lot of false positives and it misses some languages. A project consisting of some C, C++, ObjC and it claims to see C, C++, D, Fortran, Shell, Python. If I analyze the ObjC directory all by itself then it works fine but misses all the other languages. Very flakey.
So does anyone have a good tool to generate some basic stats on which languages are being used in a very large project?
UPDATE:
Tried https://github.com/blackducksw/ohcount/
Similar story to linguist but provided a ton more details. A bit hit and miss at times though.
Give SLOCCount a try. It can identify numerous programming languages and does some interesting statistics (such as estimated development costs).