Function mutateTextContent

packages/cli/src/transform.ts:568–693

(
  target: any,
  originalText: string,
  newText: string,
  source?: string,
  cursorOffset?: number,
  textAnchor?: TextEditAnchor,
)

 * 3. Expression match: text is in a JSXExpressionContainer StringLiteral
 */
export function mutateTextContent(
  target: any,
  originalText: string,
  newText: string,
  source?: string,
  cursorOffset?: number,
  textAnchor?: TextEditAnchor,
): boolean {
  const children = target.node.children;
  const tag = target.node.openingElement?.name?.name || target.node.openingElement?.name?.property?.name || "?";
  const line = target.node.openingElement?.loc?.start?.line;
  const finish = (): true => {
    canonicalizeEditedTextSubtree(target.node, source);
    return true;
  };
  logger.debug(`[mutateText] target=<${tag}> line=${line} children=${children?.length ?? "null"} original="${originalText.slice(0,60)}" new="${newText.slice(0,60)}"`);
  if (!children) return false;

  // Diagnostic: dump children types and values to see what we're working with
  for (let i = 0; i < children.length; i++) {
    const c = children[i];
    if (c.type === "JSXText") {
      logger.debug(`[mutateText]   child[${i}] JSXText: "${c.value.slice(0, 80).replace(/\n/g, "\\n")}"`);
    } else if (c.type === "JSXElement") {
      const childTag = c.openingElement?.name?.name || c.openingElement?.name?.property?.name || "?";
      logger.debug(`[mutateText]   child[${i}] JSXElement: <${childTag}>`);
    } else if (c.type === "JSXExpressionContainer") {
      logger.debug(`[mutateText]   child[${i}] JSXExpr: ${c.expression?.type} = "${String(c.expression?.value ?? c.expression?.type).slice(0, 60)}"`);
    } else {
      logger.debug(`[mutateText]   child[${i}] ${c.type}`);
    }
  }

  // Case 1: Exact match against a single JSXText child
  // Use normalizeWs because React collapses JSX whitespace (newlines → spaces)
  // but the AST retains raw whitespace — DOM textContent won't match without this.
  for (let i = 0; i < children.length; i++) {
    const child = children[i];
    if (child.type === "JSXText") {
      const trimmed = child.value.trim();
      if (normalizeWs(trimmed) === normalizeWs(originalText.trim())) {
        const idx = child.value.indexOf(trimmed);
        const prefixWs = child.value.slice(0, idx);
        const suffixWs = child.value.slice(idx + trimmed.length);
        child.value = prefixWs + newText + suffixWs;
        return finish();
      }
    }
    if (
      child.type === "JSXExpressionContainer" &&
      child.expression.type === "StringLiteral" &&
      child.expression.value === originalText
    ) {
      child.expression.value = newText;
      return finish();
    }
  }