public void NursesFile_OpenText_WithFileThatDoesNotExist_ThrowsError()
        {
            var fileName   = "does.not.exist";
            var nursesFile = new NursesFile(fileName);

            Assert.Throws <FileNotFoundException>(() =>
                                                  nursesFile.OpenText());
        }
        public void NursesFile_OpenText_WithDirectoryThatDoesNotExist_ThrowsError()
        {
            var fileName   = "does/not/exist.csv";
            var nursesFile = new NursesFile(fileName);

            Assert.Throws <DirectoryNotFoundException>(() =>
                                                       nursesFile.OpenText());
        }