customize-with-attribute.md

CustomizeWith Attribute

An attribute that can be applied to parameters in an AutoDataAttribute-driven Theory to apply additional customization when the IFixture creates an instance of that type.

Arguments

• IncludeParameterType - indicates whether attribute target parameter Type should be included as a first argument when creating customization; by default set to false

Caution: Order is important! Applying CustomizeWith attribute to the subsequent parameter makes preceding parameters of the same type to be created without specified customization and the particular parameter with the specified customization.

Example

public class LocalDatesCustomization : ICustomization
{
    public void Customize(IFixture fixture)
    {
        fixture.Register(() => LocalDate.FromDateTime(fixture.Create<DateTime>()));
    }
}

[Theory]
[InlineAutoMockData("USD")]
[InlineAutoMockData("EUR")]
public void GivenCurrencyConverter_WhenConvertToPlnAtParticularDay_ThenMustReturnCorrectConvertedAmount(
    string testCurrencySymbol,
    [CustomizeWith(typeof(LocalDatesCustomization))] LocalDate day,
    [Frozen] ICurrencyExchangeProvider currencyProvider,
    CurrencyConverter currencyConverter)
{
    // Arrange
    Mock.Get(currencyProvider)
        .Setup(cp => cp.GetCurrencyExchangeRate(testCurrencySymbol, day))
        .Returns(100M);

    // Act
    decimal result = currencyConverter.ConvertToPln(testCurrencySymbol, 100M, day);

    // Assert
    Assert.Equal(10000M, result);
}