import baseToString from './_baseToString.js'; import castSlice from './_castSlice.js'; import hasUnicode from './_hasUnicode.js'; import isObject from './isObject.js'; import isRegExp from './isRegExp.js'; import stringSize from './_stringSize.js'; import stringToArray from './_stringToArray.js'; import toInteger from './toInteger.js'; import toString from './toString.js'; /** Used as default options for `_.truncate`. */ var DEFAULT_TRUNC_LENGTH = 30, DEFAULT_TRUNC_OMISSION = '...'; /** Used to match `RegExp` flags from their coerced string values. */ var reFlags = /\w*$/; /** * Truncates `string` if it's longer than the given maximum string length. * The last characters of the truncated string are replaced with the omission * string which defaults to "...". * * @static * @memberOf _ * @since 4.0.0 * @category String * @param {string} [string=''] The string to truncate. * @param {Object} [options={}] The options object. * @param {number} [options.length=30] The maximum string length. * @param {string} [options.omission='...'] The string to indicate text is omitted. * @param {RegExp|string} [options.separator] The separator pattern to truncate to. * @returns {string} Returns the truncated string. * @example * * _.truncate('hi-diddly-ho there, neighborino'); * // => 'hi-diddly-ho there, neighbo...' * * _.truncate('hi-diddly-ho there, neighborino', { * 'length': 24, * 'separator': ' ' * }); * // => 'hi-diddly-ho there,...' * * _.truncate('hi-diddly-ho there, neighborino', { * 'length': 24, * 'separator': /,? +/ * }); * // => 'hi-diddly-ho there...' * * _.truncate('hi-diddly-ho there, neighborino', { * 'omission': ' [...]' * }); * // => 'hi-diddly-ho there, neig [...]' */ function truncate(string, options) { var length = DEFAULT_TRUNC_LENGTH, omission = DEFAULT_TRUNC_OMISSION; if (isObject(options)) { var separator = 'separator' in options ? options.separator : separator; length = 'length' in options ? toInteger(options.length) : length; omission = 'omission' in options ? baseToString(options.omission) : omission; } string = toString(string); var strLength = string.length; if (hasUnicode(string)) { var strSymbols = stringToArray(string); strLength = strSymbols.length; } if (length >= strLength) { return string; } var end = length - stringSize(omission); if (end < 1) { return omission; } var result = strSymbols ? castSlice(strSymbols, 0, end).join('') : string.slice(0, end); if (separator === undefined) { return result + omission; } if (strSymbols) { end += (result.length - end); } if (isRegExp(separator)) { if (string.slice(end).search(separator)) { var match, substring = result; if (!separator.global) { separator = RegExp(separator.source, toString(reFlags.exec(separator)) + 'g'); } separator.lastIndex = 0; while ((match = separator.exec(substring))) { var newEnd = match.index; } result = result.slice(0, newEnd === undefined ? end : newEnd); } } else if (string.indexOf(baseToString(separator), end) != end) { var index = result.lastIndexOf(separator); if (index > -1) { result = result.slice(0, index); } } return result + omission; } export default truncate;