public void CanAddProduct_NullProduct_ThrowsException()
{
// Arrange
ProductValidator productValidator = new ProductValidator();
Product product = null;
// Act
// Assert
Assert.ThrowsException <ArgumentNullException>(() => productValidator.CanAddProduct(product));
}
public void CanAddProduct_ProductHasEmptyPrice_ReturnErrorMessage()
{
// Arrange
ProductValidator productValidator = new ProductValidator();
Product product = new Product();
product.Name = "Name";
product.Description = "Description";
// Act
List <KeyValuePair <string, string> > result = productValidator.CanAddProduct(product);
// Assert
Assert.IsNotNull(result);
Assert.AreEqual(1, result.Count);
Assert.AreEqual("Price", result[0].Key);
}