Function normalizeScript

packages/just-bash/src/Bash.ts:879–922

* Normalize a script by stripping leading whitespace from lines, * while preserving whitespace inside heredoc content. * * This allows writing indented bash scripts in template literals: * ``` * await bash.exec(` * if [ -f foo ]; then * echo "yes" * fi * `); * ``` * * Heredocs ar

(script: string)

 * Heredocs are detected by looking for << or <<- operators and their delimiters.
 */
function normalizeScript(script: string): string {
  const lines = script.split("\n");
  const result: string[] = [];

  // Stack of pending heredoc delimiters (for nested heredocs)
  const pendingDelimiters: { delimiter: string; stripTabs: boolean }[] = [];

  for (let i = 0; i < lines.length; i++) {
    const line = lines[i];

    // If we're inside a heredoc, check if this line ends it
    if (pendingDelimiters.length > 0) {
      const current = pendingDelimiters[pendingDelimiters.length - 1];
      // For <<-, strip leading tabs when checking delimiter
      // For <<, require exact match (no leading whitespace allowed)
      const lineToCheck = current.stripTabs ? line.replace(/^\t+/, "") : line;
      if (lineToCheck === current.delimiter) {
        // End of heredoc - this line can be normalized
        result.push(line.trimStart());
        pendingDelimiters.pop();
        continue;
      }
      // Inside heredoc - preserve the line exactly as-is
      result.push(line);
      continue;
    }

    // Not inside a heredoc - normalize the line and check for heredoc starts
    const normalizedLine = line.trimStart();
    result.push(normalizedLine);

    // Check for heredoc operators in this line
    // Match: <<DELIM, <<-DELIM, << 'DELIM', <<- "DELIM", etc.
    // Multiple heredocs on one line are possible: cmd <<EOF1 <<EOF2
    const heredocPattern = /<<(-?)\s*(['"]?)([\w-]+)\2/g;
    for (const match of normalizedLine.matchAll(heredocPattern)) {
      const stripTabs = match[1] === "-";
      const delimiter = match[3];
      pendingDelimiters.push({ delimiter, stripTabs });
    }
  }

  return result.join("\n");
}

/**
 * Strict UTF-8 decoder that throws on invalid byte sequences.