Background: I linked my package with npm link, which creates a symlink and includes all the source files and everything in the node_modules folder, so I was quite surprised to see how large the patch was. Providing this flag therefore seems quite logical for me.

I do not consider this implementation complete - it does what I needed, but I didn't add any tests, and haven't checked how it works together with --include/exclude etc. So, maintainers, please provide feedback if this is something you want to add.