bUnitでBlazorのパラメーターテストを極める

@typeparam TItem where TItem : CheckBox, ICloneable

<button id="titleButton" type="button" class="btn btn-primary m-2" data-bs-toggle="modal" data-bs-target="#countryModal">
	@Title
</button>

<div class="modal fade" id="countryModal" data-bs-backdrop="static" data-bs-keyboard="false">
	<div class="modal-dialog">
		<div class="modal-content">
			<div class="modal-header">
				@HeaderContent
				<button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close" @onclick="Reset"></button>
			</div>
			<div class="d-flex">
				<div class="modal-body">
						@foreach (var c in List)
					{
						<div class="form-check">
							<input class="form-check-input" type="checkbox" id="@c.Name" @bind="c.IsChecked" />
							<label class="form-check-label" for="@c.Name">@c.Displayname</label>
						</div>
					}
				</div>
			</div>

			<div class="modal-footer">
				<button id="setButton" type="button" class="btn btn-primary" data-bs-dismiss="modal" @onclick="SetEvent">設定</button>
			</div>
		</div>
	</div>
</div>

@code {
	[CascadingParameter]
	public string? Title { get; set; }

	[Parameter]
	public List<TItem> List { get; set; } = default!;

	[Parameter]
	public RenderFragment? HeaderContent { get; set; }

	[Parameter]
	public EventCallback<List<TItem>> ListChanged { get; set; }

	private List<TItem> BackupList { get; set; } = default!;

	private async Task SetEvent() => await ListChanged.InvokeAsync(List);

	protected override void OnParametersSet()
	{
		BackupList = List.Select(item => (TItem)item.Clone()).ToList();
	}
	private void Reset()
	{
		List = BackupList.Select(item => (TItem)item.Clone()).ToList();
	}
}

<CascadingValue Value="@title">
	<CustomModal TItem="Country" @bind-List="Countries">
		<HeaderContent>
			<h3>国を選択</h3>
		</HeaderContent>
	</CustomModal>
</CascadingValue>

	[Fact]
	public void ModalParameterTest()
	{
		// Arrange
		var list = new List<Country>()
		{
			new Country {Name="Japan",Displayname="日本",IsChecked=true},
			new Country {Name="US",Displayname="アメリカ",IsChecked=false}
		};
		var cut = RenderComponent<CustomModal<Country>>(parameters => parameters
			.Add(p => p.List, list)
			);
		var countries = cut.FindAll(".form-check-input");

		// Assert
		Assert.Equal(2, countries.Count);
		Assert.Equal("US", countries[1].Id);
		Assert.False(countries[1].IsChecked());
	}

	[Fact]
	public void ModalCascadTest()
	{
		// Arrange
		var cut = RenderComponent<CustomModal<Country>>(parameters => parameters
			.Add(p => p.Title, "Test Title")
			);
		var titleButton = cut.Find("#titleButton");

		// Assert

		Assert.Equal("Test Title", titleButton.InnerHtml);
	}

	[Fact]
	public void ModalRendarFragmentTest()
	{
		// Arrange
		var cut = RenderComponent<CustomModal<Country>>(parameters => parameters
			.Add(p => p.HeaderContent, "<h3>Header</h3>")
			);
		var header = cut.Find("h3");

		// Assert
		Assert.Equal("Header", header.InnerHtml);

	}

	[Fact]
	public void ModalEventTest()
	{
		// Arrange
		var list = new List<Country>()
		{
			new Country {Name="Japan",Displayname="日本",IsChecked=true},
			new Country {Name="US",Displayname="アメリカ",IsChecked=false}
		};
		Action listChanged = () => { };

		var resultList = new List<Country>();

		var cut = RenderComponent<CustomModal<Country>>(parameters => parameters
			.Bind(p => p.List, list, newList => list = newList)
			);
		var countries = cut.FindAll(".form-check-input");
		var checkBox = countries[1];
		var button = cut.Find("#setButton");

		checkBox.Change(true);
		button.Click();
		cut.Render();
		countries = cut.FindAll(".form-check-input");
		checkBox = countries[1];

		// Assert
		Assert.Equal(2, countries.Count);
		Assert.Equal("US", countries[1].Id);
		Assert.True(countries[1].IsChecked());
		Assert.True(list[1].IsChecked);
	}

<PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>
    <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
</PropertyGroup>