src/document/doc-builders.js/addAlignmentToDoc
function addAlignmentToDoc(doc, size, tabWidth) {
  let aligned = doc;
  if (size > 0) {
    // Use indent to add tabs for all the levels of tabs we need
    for (let i = 0; i < Math.floor(size / tabWidth); ++i) {
      aligned = indent(aligned);
    }
    // Use align for all the spaces that are needed
    aligned = align(size % tabWidth, aligned);
    // size is absolute from 0 and not relative to the current
    // indentation, so we use -Infinity to reset the indentation to 0
    aligned = align(-Infinity, aligned);
  }
  return aligned;
}