ReadAdTest.cs

using System.Threading.Tasks;
using ContosoAds.Web.Commands;
using ContosoAds.Web.Model;
using static ContosoAds.Web.UnitTests.TestSupport;

namespace ContosoAds.Web.UnitTests;

public class ReadAdTest
{
    [Fact]
    public async Task It_Finds_Ad()
    {
        // Arrange
        const int adId = 1;
        var dbContext = await CreateTestDbContext(
            nameof(ReadAdTest),
            true,
            new Ad {Id = adId, Title = "Test Ad", Phone = "425-555-1212", Price = 42});

        // Act
        var command = new ReadAd(dbContext);
        var foundAd = await command.ExecuteAsync(adId);

        // Assert
        Assert.Equal(adId, foundAd?.Id);
    }

    [Fact]
    public async Task It_Returns_Null_If_Ad_Does_Not_Exist()
    {
        // Arrange
        var dbContext = await CreateTestDbContext(nameof(ReadAdTest), true, new Ad {Id = 1, Title = "Test Ad", Phone = "425-555-1212", Price = 42});

        // Act
        var command = new ReadAd(dbContext);
        var foundAd = await command.ExecuteAsync(2);

        // Assert
        Assert.Null(foundAd);
    }
}