toSnakeCase static method

String toSnakeCase(String raw)

Converts raw into a Dart-friendly snake_case identifier.

Non-alphanumeric separators are collapsed to underscores, camel-case boundaries are split, and the final value is lowercased.

Throws a FormatException when the normalized value is empty or starts with a number.

Implementation

static String toSnakeCase(String raw) {
  final normalized = raw
      .trim()
      .replaceAllMapped(
        RegExp(r'([a-z0-9])([A-Z])'),
        (match) => '${match[1]}_${match[2]}',
      )
      .replaceAll(RegExp(r'[^A-Za-z0-9]+'), '_')
      .replaceAll(RegExp(r'_+'), '_')
      .replaceAll(RegExp(r'^_|_$'), '')
      .toLowerCase();

  if (normalized.isEmpty) {
    throw const FormatException('Name must not be empty.');
  }

  if (RegExp(r'^[0-9]').hasMatch(normalized)) {
    throw const FormatException('Name must not start with a number.');
  }

  return normalized;
}