public async Task DeleteManager_WhenCalled_DeleteManagerFromDb()
{
const int id = 1;
var expectedManager = new Manager
{
Id = id
};
_managerService.Setup(m => m.GetByIdAsync(id)).ReturnsAsync(expectedManager);
var result = await _managersController.DeleteManager(id);
var okObjectResult = result as OkObjectResult;
_managerService.Verify(m => m.DeleteAsync(It.IsAny <Manager>()), Times.Once);
Assert.That(result, Is.TypeOf <OkObjectResult>());
Assert.That(okObjectResult.Value, Is.EqualTo(id));
}