def METHOD_NAME(self):
    """The log file should start with a line describing the study.
    A subsequent study should have its own header line.
    """
    # given
    with TemporaryDirectory() as out_dir_path:
        args = [
            '--root-directory', 'test_data',
            '--list-of-studies', 'study_various_issues,study_es_0',
            '--portal_info_dir', PORTAL_INFO_DIR,
            '--html-folder', out_dir_path
            ]
        # when
        with redirect_stdout(StringIO()):
            parsed_args = validateStudies.interface(args)
            validateStudies.main(parsed_args)
        # then
        log_file_path = glob.glob(os.path.join(out_dir_path, 'log*.txt'))[0]
        with open(log_file_path) as log_file:
            log_file_lines = log_file.readlines()
        self.assertIn('study_various_issues', log_file_lines[0])
        last_line_of_first_study = next(
            index
            for index, line
            in enumerate(log_file_lines)
            if 'Validation complete' in line)
        self.assertIn(
            'study_es_0',
            log_file_lines[last_line_of_first_study + 1])