Function quoteFileNameIfNeeded

src/patch/create.ts:29–72

* C-style quotes a filename, encoding special characters as escape sequences * and non-ASCII bytes as octal escapes. This is the inverse of * `parseQuotedFileName` in parse.ts. * * Non-ASCII bytes are encoded as UTF-8 before being emitted as octal escapes. * This matches the behaviour of both G

(s: string)

 * If the filename doesn't need quoting, returns it as-is.
 */
function quoteFileNameIfNeeded(s: string): string {
  if (!needsQuoting(s)) {
    return s;
  }

  let result = '"';
  const bytes = new TextEncoder().encode(s);
  let i = 0;
  while (i < bytes.length) {
    const b = bytes[i];

    // See https://en.wikipedia.org/wiki/Escape_sequences_in_C#Escape_sequences
    if (b === 0x07) {
      result += '\\a';
    } else if (b === 0x08) {
      result += '\\b';
    } else if (b === 0x09) {
      result += '\\t';
    } else if (b === 0x0a) {
      result += '\\n';
    } else if (b === 0x0b) {
      result += '\\v';
    } else if (b === 0x0c) {
      result += '\\f';
    } else if (b === 0x0d) {
      result += '\\r';
    } else if (b === 0x22) {
      result += '\\"';
    } else if (b === 0x5c) {
      result += '\\\\';
    } else if (b >= 0x20 && b <= 0x7e) {
      // Just a printable ASCII character that is neither a double quote nor a
      // backslash; no need to escape it.
      result += String.fromCharCode(b);
    } else {
      // Either part of a non-ASCII character or a control character without a
      // special escape sequence; needs escaping as a 3-digit octal escape
      result += '\\' + b.toString(8).padStart(3, '0');
    }
    i++;
  }
  result += '"';
  return result;
}

type StructuredPatchCallbackAbortable = (patch: StructuredPatch | undefined) => void;
type StructuredPatchCallbackNonabortable = (patch: StructuredPatch) => void;