Display notice depending on the contents in WordPress block editor

block-editor-notice.js

/*!
 * Test document.
 *
 * @deps wp-data, wp-dom-ready
 */

const { data, domReady } = wp;

const wordLimiter = {
	80: false,
	140: false,
};

const stripTags = ( text ) => {
	// Remove comment.
	text = text.replace( /<!--(.*?)-->/g, '' );
	// Remove tags.
	text = text.replace( /<([^>]+)>/g, '' );
	// Remove sequential line breaks.
	text = text.replace( /\n{2,}/g, "\n" );
	return text;
};

domReady( () => {
	// 
	data.subscribe( () => {
		const count = stripTags( data.select( 'core/editor' ).getEditedPostContent() ).length;
		if ( ! wordLimiter[80] && 80 < count ) {
			wordLimiter[80] = true;
			data.dispatch( 'core/notices' ).createNotice( 'success', 'Great, you\'ve written 80 letters long.', {
				type: 'snackbar'
			} ).then( ( res ) => {
				setTimeout( () => {
					data.dispatch( 'core/notices' ).removeNotice( res.notice.id );
				}, 3000 );
			} );
		} else if ( ! wordLimiter[140] && 140 < count ) {
			wordLimiter[140] = true;
			data.dispatch( 'core/notices' ).createNotice( 'error', 'Over 140 letter, too long!', {
				type: 'snackbar'
			} ).then( ( res ) => {
				setTimeout( () => {
					data.dispatch( 'core/notices' ).removeNotice( res.notice.id );
				}, 3000 );
			} );
		}
	} );
} );