Function classMatchesPrefix

packages/cli/src/transform.ts:290–299

* Check whether a class string matches a given Tailwind prefix. * E.g. prefix "p" matches "p-4", "p-[13px]", but not "px-4" or "pl-2".

(cls: string, prefix: string)

 * E.g. prefix "p" matches "p-4", "p-[13px]", but not "px-4" or "pl-2".
 */
function classMatchesPrefix(cls: string, prefix: string): boolean {
  // Skip variant-prefixed classes (e.g. hover:bg-blue-700, dark:bg-gray-900).
  // These are intentional state/responsive overrides and should not be
  // matched when replacing the base utility class.
  if (cls.includes(":")) return false;
  // Exact match for standalone classes like "rounded"
  if (cls === prefix) return true;
  // prefix- followed by something
  return cls.startsWith(`${prefix}-`);
}

/**
 * Apply a single update to an array of class strings.