code: function forceBreakContent(node) {
    return (
      forceBreakChildren(node) ||
      (node.type === "element" &&
        node.children.length !== 0 &&
        (["body", "template", "script", "style"].indexOf(node.name) !== -1 ||
          node.children.some(child => hasNonTextChild(child)))) ||
      (node.firstChild &&
        node.firstChild === node.lastChild &&
        (hasLeadingLineBreak(node.firstChild) &&
          (!node.lastChild.isTrailingSpaceSensitive ||
            hasTrailingLineBreak(node.lastChild))))
    );
  }
docs: firstChild leadingSpaces and lastChild trailingSpaces