matchesTypeahead

Description#

Case-insensitive prefix match between an item label and a typeahead query term - THE matching semantic of every cngx typeahead surface.

CngxActiveDescendant applies it to the rendered window on every buffered keystroke; CngxTreeSelect's expand-to-reveal miss search applies it to the full flat tree. Both MUST agree on what "matches" means - a revealed node that the rendered-window walk would then skip (or vice versa) breaks the type-to-find contract. Change the semantic here (e.g. locale folding, includes fallback) and every consumer moves together.

Both sides are lowercased, so pre-lowercased buffer terms and raw user input behave identically. An empty term matches every label (startsWith('') is true) - callers gate on a non-empty buffer.

matchesTypeahead('Postgres', 'p');   // true
matchesTypeahead('Postgres', 'PO');  // true
matchesTypeahead('Postgres', 'g');   // false - prefix, not substring