OptionsNode flattenOptions()

in lib/src/ast.dart [70:105]
30 lines of code
6 McCabe index (conditional complexity)

  OptionsNode flattenOptions() {
    if (nodes.isEmpty) {
      return OptionsNode([this], caseSensitive: caseSensitive);
    }

    var sequences =
        nodes.first.flattenOptions().options.map((sequence) => sequence.nodes);
    for (var node in nodes.skip(1)) {
      // Concatenate all sequences in the next options node ([nextSequences])
      // onto all previous sequences ([sequences]).
      var nextSequences = node.flattenOptions().options;
      sequences = sequences.expand((sequence) {
        return nextSequences.map((nextSequence) {
          return sequence.toList()..addAll(nextSequence.nodes);
        });
      });
    }

    return OptionsNode(sequences.map((sequence) {
      // Combine any adjacent LiteralNodes in [sequence].
      return SequenceNode(
          sequence.fold<List<AstNode>>([], (combined, node) {
            if (combined.isEmpty ||
                combined.last is! LiteralNode ||
                node is! LiteralNode) {
              return combined..add(node);
            }

            combined[combined.length - 1] = LiteralNode(
                (combined.last as LiteralNode).text + node.text,
                caseSensitive: caseSensitive);
            return combined;
          }),
          caseSensitive: caseSensitive);
    }), caseSensitive: caseSensitive);
  }