public static async Task ShouldAddNode <TNode>(this IMixerViewModel mixer,
Point point,
IInteractionService interactions,
INodeFactory nodeFactory,
Func <IMixerViewModel, Task> command)
where TNode : INode
{
// Arrange
var isInvoked = false;
interactions.GetNewNodePoint
.RegisterHandler(i =>
{
isInvoked = true;
i.SetOutput(point);
});
// Act
mixer.Activator
.Activate();
await command(mixer);
var node = mixer.Nodes.Single();
// Assert
isInvoked.Should().BeTrue();
nodeFactory.Received().Create <TNode>();
node.Should().BeAssignableTo <TNode>();
node.X.Should().Be(point.X);
node.Y.Should().Be(point.Y);
}