public void DecodeAsString_ToStringEncoded() { // Arrange var context = new TestCaseContext(); var sut = new Base64Encoder( context.Options, context.Logger, context.StringEncoder); var data = "MTIz"; // Act sut.DecodeAsString(data); // Assert Mock.Get(context.StringEncoder).Verify( m => m.EncodeToString(It.IsAny <byte[]>()), Times.Once); }