https://github.com/ggreer/the_silver_searcher/issues/385
its been over 4 years... its had its chance.
But you know there's a -r for recursive, right? And unless you are using some historic relic of grep that is not GNU or BSD and doesn't understand the --include option you can just do:
grep -rin "needle" --include "*.foo" .
find . -iname '.*' -prune -o -iname '*.foo' -exec grep needle {} +
Modern file searchers, of which `ag` is one among others, accepts `--filenametype` argument and skips the `.git` subdirectory if it exists (by default, can be toggled), so `ag --python needle` will recursively search for needle in the the current working tree in all files whos filenames end in `.py`.
Yes, you could write a function to do the same in `find`, but then you're just being stubborn. (Which is fine; my .bashrc is littered with aliases and functions of me being stubborn, but if I have to copy my .bashrc file around, I might as well install my preferred searcher to the target system if available.)
Use --include and --exclude-dirs to do what you describe. (The latter is a good idea to set in your GREP_OPTIONS, unless you actually search .git directories.)
(I don't think there's any such plan for the various BSD greps, so if you use those exclusively you're probably fine.)