lineNumberForOffset function

int? lineNumberForOffset(
  1. String text,
  2. int? offset
)

1-based line number for offset, or null when unknown.

Implementation

int? lineNumberForOffset(String text, int? offset) {
  if (offset == null || offset < 0) return null;
  final clamped = offset.clamp(0, text.length);
  return '\n'.allMatches(text.substring(0, clamped)).length + 1;
}