Can't resolve `name.first_name` with Faker

I am trying to generate some values for my test.

I try to get all keys from a file.

When I try to generate a first name I got this error:

Faker faker = new Faker();
faker.resolve("name.first_name")

Unable to resolve #{male_first_name} directive.

That is probably because first_name is recursive.

That works fine with name.last_name.

Because I want to have key definitions from outside, I can't call faker.name().firstName()

Any Idea?