When the (first) name of generated output has spaces, the result is invalid.

Here's an example:
{"name":"","surname":"María Carmen Rodríguez","gender":"female","region":"Spain"}

The name (which was originally 'María Carmen') is empty and instead put into the surname.

Other examples that currently break:
Name: "A B", Surname: "C"
Current: Name: "", Surname: "A B C"

Name: "A B C", Surname: "D"
Current: Name: "A", Surname: "B C D"

Name: "A B C", Surname: "D E"
Current: Name: "A", Surname: "B C D E"