I'm not super happy with this. For some context, directory contains the top-level functions directory where this specific function is found (not the sub-directory where a function may live). For example, for both netlify/functions/foo/index.js and netlify/functions/bar.js this value would be netlify/functions.

This value was undefined for any functions in generatedFunctions, because those functions don't typically live inside any of the regular function directories. So for those cases the right value to use is srcDir.

I think this is in need of some refactoring though, because I'm not sure why we need to keep track of the parent functions directory and not just the directory where the function lives.

I'm keeping this as is for now, where we're just adding srcDir as a fallback, to minimise the impact of this change, and then we'll revisit when possible.