This is a test project for golang/go#71783.

The main package does these things:

• Runs a function Foo defined in internal/foo/foo.go. This function just outputs 'Original' by default.
• Runs go list -f {{.Dir}} github.com/hajimehoshi/overlaytest/internal/foo to get the local path for the package.
• Generates a JSON file to add a new file internal/foo/bar.go to replace the output message to 'Replaced'.