Function serializeElement

xml/stringify.ts:91–137

* Serializes an XML element and its children to a string.

(
  element: XmlElement,
  indent: string | undefined,
  depth: number,
  getIndent?: (depth: number) => string,
)

 * Serializes an XML element and its children to a string.
 */
function serializeElement(
  element: XmlElement,
  indent: string | undefined,
  depth: number,
  getIndent?: (depth: number) => string,
): string {
  // Initialize indent cache on first call
  const indentFn = getIndent ?? createIndentCache(indent);
  const prefix = indentFn(depth);
  const newline = indent !== undefined ? "\n" : "";

  // Build tag name (with optional namespace prefix)
  const tagName = element.name.prefix
    ? `${element.name.prefix}:${element.name.local}`
    : element.name.local;

  // Build attributes string
  let attrsStr = "";
  for (const [name, value] of Object.entries(element.attributes)) {
    attrsStr += ` ${name}="${encodeAttributeValue(value)}"`;
  }

  // Self-closing tag if no children
  if (element.children.length === 0) {
    return `${prefix}<${tagName}${attrsStr}/>`;
  }

  // Check if all children are inline content (text or cdata only)
  const hasOnlyInlineContent = element.children.every(
    (child) => child.type === "text" || child.type === "cdata",
  );

  if (hasOnlyInlineContent) {
    // Inline: <tag>content</tag> (no indentation for content)
    const content = element.children
      .map((child) => serializeNode(child, undefined, 0, indentFn))
      .join("");
    return `${prefix}<${tagName}${attrsStr}>${content}</${tagName}>`;
  }

  // Block: children on separate lines (when indenting)
  const childContent = element.children
    .map((child) => serializeNode(child, indent, depth + 1, indentFn))
    .join(newline);

  return `${prefix}<${tagName}${attrsStr}>${newline}${childContent}${newline}${prefix}</${tagName}>`;
}

/**
 * Serializes any XML node to a string.