convertReportsFrom function

List<Map<String, Object?>> convertReportsFrom(Object? json)

The reports a --report file holds, each as ConvertReport.toJson wrote it: from the enveloped document, or from the bare list the file was before 1.0.

Throws a DocumentFormatException for another format's document, a newer version, or a document with no list of reports.

Implementation

List<Map<String, Object?>> convertReportsFrom(Object? json) {
  final list = switch (json) {
    final List<Object?> bare => bare,
    final Map<String, Object?> document => switch (convertReportFormat.read(
      document,
      refuse: DocumentFormatException.new,
    )['reports']) {
      final List<Object?> reports => reports,
      _ => throw const DocumentFormatException(
        'a convert report with no "reports" list',
      ),
    },
    _ => throw const DocumentFormatException(
      'a convert report is a JSON object with "reports"',
    ),
  };
  return <Map<String, Object?>>[
    for (final each in list)
      if (each is Map<String, Object?>)
        each
      else
        throw DocumentFormatException('a convert report entry is $each'),
  ];
}