public void WhenEnrollmentFileHasInvalidDateOfBirthFormat_ThenReturnMinimumDateTimeValue() { var filePath = "enrollments.csv"; var fileReader = new Mock <IFileReader>(MockBehavior.Strict); var enrollmentReader = new EnrollmentReaderCSV(); var enrollmentCSVLines = new List <string> { "Jane,Doe,612002,HSA,06012020", }; fileReader.Setup(x => x.ReadLines(It.IsAny <string>())).Returns(enrollmentCSVLines); var enrollmentRecords = enrollmentReader.ReadFromFile(fileReader.Object, filePath).ToList(); Assert.IsTrue(enrollmentRecords.Count == 1); Assert.IsTrue(enrollmentRecords[0].DateOfBirth == DateTime.MinValue); }