public void TestOnDelete()
{
var mockSet = GenerateMock();
var mockContext = new Mock <CompanyDBEntities>();
mockContext.Setup(m => m.Companies).Returns(mockSet.Object);
var companyContext = new CompanyDBContext(mockContext.Object);
companyContext.DeleteCompany(companyContext.FindCompanyById(1));
mockSet.Verify(m => m.Remove(It.IsAny <Company>()), Times.Once());
}