normalizeInput function

String normalizeInput(
  1. String input
)

Strip leading/trailing whitespace and normalize newlines.

Implementation

String normalizeInput(String input) {
  // Normalize CRLF and bare CR to LF.
  var result = input.replaceAll('\r\n', '\n').replaceAll('\r', '\n');

  // Strip trailing whitespace per line.
  result = result.split('\n').map((line) => line.trimRight()).join('\n');

  // Strip leading/trailing blank lines but preserve internal structure.
  result = result.trim();

  return result;
}