On a somewhat related note.
There does not appear be a popular indexed full-text search tool in existence.
Think cross-platform version of Spotlight's mdfind. Could there be something fundamental that makes this approach unsuitable for code search?
Alternatively, something like locate, but realtime and fulltext, instead of filename only.
AFAIK mdfind heavily depends on file system events in macOS, it would be painful or impossible to implement such system in cross platform way with support for file systems like FAT etc.
sure, FAT. OTOH some people think it's not a totally intractable problem
A cross-platform file change monitor with multiple backends: Apple OS X File System Events, BSD kqueue, Solaris/Illumos File Events Notification, Linux inotify, Microsoft Windows and a stat()-based backend.