@wordpress/wordcount/src/index.js

WordPress word count utility.

/**
 * Internal dependencies
 */
import { defaultSettings } from './defaultSettings';
import stripTags from './stripTags';
import transposeAstralsToCountableChar from './transposeAstralsToCountableChar';
import stripHTMLEntities from './stripHTMLEntities';
import stripConnectors from './stripConnectors';
import stripRemovables from './stripRemovables';
import stripHTMLComments from './stripHTMLComments';
import stripShortcodes from './stripShortcodes';
import stripSpaces from './stripSpaces';
import transposeHTMLEntitiesToCountableChars from './transposeHTMLEntitiesToCountableChars';

/**
 * @typedef {import('./defaultSettings').WPWordCountDefaultSettings}  WPWordCountSettings
 * @typedef {import('./defaultSettings').WPWordCountUserSettings}     WPWordCountUserSettings
 */

/**
 * Possible ways of counting.
 *
 * @typedef {'words'|'characters_excluding_spaces'|'characters_including_spaces'} WPWordCountStrategy
 */

/**
 * Private function to manage the settings.
 *
 * @param {WPWordCountStrategy}     type         The type of count to be done.
 * @param {WPWordCountUserSettings} userSettings Custom settings for the count.
 *
 * @return {WPWordCountSettings} The combined settings object to be used.
 */
function loadSettings( type, userSettings ) {
	const settings = Object.assign( {}, defaultSettings, userSettings );

	settings.shortcodes = settings.l10n?.shortcodes ?? [];

	if ( settings.shortcodes && settings.shortcodes.length ) {
		settings.shortcodesRegExp = new RegExp(
			'\\[\\/?(?:' + settings.shortcodes.join( '|' ) + ')[^\\]]*?\\]',
			'g'
		);
	}

	settings.type = type;

	if (
		settings.type !== 'characters_excluding_spaces' &&
		settings.type !== 'characters_including_spaces'
	) {
		settings.type = 'words';
	}

	return settings;
}

/**
 * Count the words in text
 *
 * @param {string}              text     The text being processed
 * @param {RegExp}              regex    The regular expression pattern being matched
 * @param {WPWordCountSettings} settings Settings object containing regular expressions for each strip function
 *
 * @return {number} Count of words.
 */
function countWords( text, regex, settings ) {
	text = [
		stripTags.bind( null, settings ),
		stripHTMLComments.bind( null, settings ),
		stripShortcodes.bind( null, settings ),
		stripSpaces.bind( null, settings ),
		stripHTMLEntities.bind( null, settings ),
		stripConnectors.bind( null, settings ),
		stripRemovables.bind( null, settings ),
	].reduce( ( result, fn ) => fn( result ), text );
	text = text + '\n';
	return text.match( regex )?.length ?? 0;
}

/**
 * Count the characters in text
 *
 * @param {string}              text     The text being processed
 * @param {RegExp}              regex    The regular expression pattern being matched
 * @param {WPWordCountSettings} settings Settings object containing regular expressions for each strip function
 *
 * @return {number} Count of characters.
 */
function countCharacters( text, regex, settings ) {
	text = [
		stripTags.bind( null, settings ),
		stripHTMLComments.bind( null, settings ),
		stripShortcodes.bind( null, settings ),
		transposeAstralsToCountableChar.bind( null, settings ),
		stripSpaces.bind( null, settings ),
		transposeHTMLEntitiesToCountableChars.bind( null, settings ),
	].reduce( ( result, fn ) => fn( result ), text );
	text = text + '\n';
	return text.match( regex )?.length ?? 0;
}

/**
 * Count some words.
 *
 * @param {string}                  text         The text being processed
 * @param {WPWordCountStrategy}     type         The type of count. Accepts 'words', 'characters_excluding_spaces', or 'characters_including_spaces'.
 * @param {WPWordCountUserSettings} userSettings Custom settings object.
 *
 * @example
 * ```js
 * import { count } from '@wordpress/wordcount';
 * const numberOfWords = count( 'Words to count', 'words', {} )
 * ```
 *
 * @return {number} The word or character count.
 */
export function count( text, type, userSettings ) {
	const settings = loadSettings( type, userSettings );
	let matchRegExp;
	switch ( settings.type ) {
		case 'words':
			matchRegExp = settings.wordsRegExp;
			return countWords( text, matchRegExp, settings );
		case 'characters_including_spaces':
			matchRegExp = settings.characters_including_spacesRegExp;
			return countCharacters( text, matchRegExp, settings );
		case 'characters_excluding_spaces':
			matchRegExp = settings.characters_excluding_spacesRegExp;
			return countCharacters( text, matchRegExp, settings );
		default:
			return 0;
	}
}