sports-division/tests/SportsDivision.Domain.Tests/StudentTests.cs

using SportsDivision.Domain.Entities;
using SportsDivision.Domain.Enums;

namespace SportsDivision.Domain.Tests;

public class StudentTests
{
    [Fact]
    public void GetAge_BirthdayNotYetPassed_ReturnsCorrectAge()
    {
        var student = new Student
        {
            DateOfBirth = new DateOnly(2010, 6, 15)
        };

        var referenceDate = new DateOnly(2024, 3, 1);
        Assert.Equal(13, student.GetAge(referenceDate));
    }

    [Fact]
    public void GetAge_BirthdayAlreadyPassed_ReturnsCorrectAge()
    {
        var student = new Student
        {
            DateOfBirth = new DateOnly(2010, 3, 15)
        };

        var referenceDate = new DateOnly(2024, 6, 1);
        Assert.Equal(14, student.GetAge(referenceDate));
    }

    [Fact]
    public void GetAge_OnBirthday_ReturnsCorrectAge()
    {
        var student = new Student
        {
            DateOfBirth = new DateOnly(2010, 6, 15)
        };

        var referenceDate = new DateOnly(2024, 6, 15);
        Assert.Equal(14, student.GetAge(referenceDate));
    }

    [Fact]
    public void GetAge_DayBeforeBirthday_ReturnsOneLess()
    {
        var student = new Student
        {
            DateOfBirth = new DateOnly(2010, 6, 15)
        };

        var referenceDate = new DateOnly(2024, 6, 14);
        Assert.Equal(13, student.GetAge(referenceDate));
    }

    [Fact]
    public void GetAge_LeapYearBirthday_Feb29_ReferenceNonLeapYear()
    {
        var student = new Student
        {
            DateOfBirth = new DateOnly(2012, 2, 29) // leap year
        };

        // March 1, 2025 - non-leap year, birthday hasn't technically passed
        var referenceDate = new DateOnly(2025, 3, 1);
        Assert.Equal(13, student.GetAge(referenceDate));
    }

    [Fact]
    public void GetAge_SameDayAsReference_ReturnsZero()
    {
        var student = new Student
        {
            DateOfBirth = new DateOnly(2024, 1, 1)
        };

        var referenceDate = new DateOnly(2024, 1, 1);
        Assert.Equal(0, student.GetAge(referenceDate));
    }

    [Fact]
    public void FullName_CombinesFirstAndLastName()
    {
        var student = new Student
        {
            FirstName = "John",
            LastName = "Doe"
        };

        Assert.Equal("John Doe", student.FullName);
    }

    [Fact]
    public void FullName_DefaultValues_ReturnsSpace()
    {
        var student = new Student();
        Assert.Equal(" ", student.FullName);
    }
}