Which of the following statements are true of TDD?

Imagine you're working in a small team and a colleague shows you some of their code and review comments. First, you look at the class under test, called Person:

public class Person {
    private String firstName;
    private String lastName;
    
    public Person(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }
    
    public String getFullName() {
        return String.format("%s %s", firstName, lastName);
    }
}

Your colleague shows you their JUnit 4 unit test for this Person class :

import Person;
import org.junit.*;

@RunWith(BlockJUnit4ClassRunner.class)
public class PersonTest {

    // check that person.getFullName() works
    public static void getFullName_shouldReturnTheFirstAndLastName_whenAPersonHasBoth() {
        // Arrange
        String expected = "Katherine Janelay";
        Person personUnderTest = new Person("Katherine", "Janelay");
        // Act
        String fullName = person.getFullName();
        // Assert
        Boolean testIsSuccessful = fullName.equals(expected);
        assert( testIsSuccessful );
        System.out.println("Passed: " + testIsSuccessful );
    }
    
    public static void main(String[] args) {
        getFullName_shouldReturnTheFirstAndLastName_whenAPersonHasBoth();
    }
}

Which of the following comments about this code are correct?

What is red-green-refactoring?