Follow symlinks (to support PNPM)

[Liamolucko]

At the moment, this doesn't work at all with PNPM, since it relies on Node following symlinks during module resolution. So I've made it follow symlinks.

It does seem to be a bit slower, if that's a concern:
Before, yarn node_modules: 400ms
After, yarn node_modules: 850ms
After, pnpm node_modules: 2.3s

[MarshallOfSound]

This is notably slower, can you maybe memoize the result of fs.realpath here? I suspect we're calling it on the same filepaths over and over again and we can make some assumptions here around those paths not changing while this is running

[Liamolucko]

Okay, that seems to have reduced yarn to 600ms and pnpm to 1.3s.

[GitMurf]

Was there ever a solution to this for pnpm? Thanks!