What?

Adds awareness functions to getSyncProvider().awareness:

// Listen for awareness updates
addListener: (
	eventType: 'update' | 'change',
	listener: AwarenessEventListener
) => void;

// Get awareness states
getStates: () => Map< number, Record< string, any > > | null;

// Set awareness field
setLocalStateField: ( field: string, value: any ) => void;

// Remove self from awareness
removeAwarenessStates: () => void;

These functions are proxied to actual awareness functions, and can be enqueued and called before awareness is available. Usage looks like this:

domReady( function () {
	const syncProvider: SyncProvider = getSyncProvider();
} );

awareness.addListener(
	'change',
	async ( { added, updated, removed }: {
		added: Array< number >;
		updated: Array< number >;
		removed: Array< number >;
	} ) => {
		const states = awareness.getStates();

		// Process updates...
	}
);

Why?

This will allow plugins to use and implement presense and awareness updates with Yjs using getSyncProvider().awareness.

How?

getSyncProvider() is bootstrapped when the editor is ready, which can make it difficult to use awareness functionality from a plugin. The implementation here uses a pending queue to immediately send/process messages when awareness functionality is ready, and the user can call getSyncProvider().awarness functions anytime. Additionally we proxy awareness functions to give the user more restricted access to the Yjs internal model.