time-to-botec

Benchmark sampling in different programming languages
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truncate.js (3357B)

      1 var baseToString = require('./_baseToString'),
      2     castSlice = require('./_castSlice'),
      3     hasUnicode = require('./_hasUnicode'),
      4     isObject = require('./isObject'),
      5     isRegExp = require('./isRegExp'),
      6     stringSize = require('./_stringSize'),
      7     stringToArray = require('./_stringToArray'),
      8     toInteger = require('./toInteger'),
      9     toString = require('./toString');
     10 
     11 /** Used as default options for `_.truncate`. */
     12 var DEFAULT_TRUNC_LENGTH = 30,
     13     DEFAULT_TRUNC_OMISSION = '...';
     14 
     15 /** Used to match `RegExp` flags from their coerced string values. */
     16 var reFlags = /\w*$/;
     17 
     18 /**
     19  * Truncates `string` if it's longer than the given maximum string length.
     20  * The last characters of the truncated string are replaced with the omission
     21  * string which defaults to "...".
     22  *
     23  * @static
     24  * @memberOf _
     25  * @since 4.0.0
     26  * @category String
     27  * @param {string} [string=''] The string to truncate.
     28  * @param {Object} [options={}] The options object.
     29  * @param {number} [options.length=30] The maximum string length.
     30  * @param {string} [options.omission='...'] The string to indicate text is omitted.
     31  * @param {RegExp|string} [options.separator] The separator pattern to truncate to.
     32  * @returns {string} Returns the truncated string.
     33  * @example
     34  *
     35  * _.truncate('hi-diddly-ho there, neighborino');
     36  * // => 'hi-diddly-ho there, neighbo...'
     37  *
     38  * _.truncate('hi-diddly-ho there, neighborino', {
     39  *   'length': 24,
     40  *   'separator': ' '
     41  * });
     42  * // => 'hi-diddly-ho there,...'
     43  *
     44  * _.truncate('hi-diddly-ho there, neighborino', {
     45  *   'length': 24,
     46  *   'separator': /,? +/
     47  * });
     48  * // => 'hi-diddly-ho there...'
     49  *
     50  * _.truncate('hi-diddly-ho there, neighborino', {
     51  *   'omission': ' [...]'
     52  * });
     53  * // => 'hi-diddly-ho there, neig [...]'
     54  */
     55 function truncate(string, options) {
     56   var length = DEFAULT_TRUNC_LENGTH,
     57       omission = DEFAULT_TRUNC_OMISSION;
     58 
     59   if (isObject(options)) {
     60     var separator = 'separator' in options ? options.separator : separator;
     61     length = 'length' in options ? toInteger(options.length) : length;
     62     omission = 'omission' in options ? baseToString(options.omission) : omission;
     63   }
     64   string = toString(string);
     65 
     66   var strLength = string.length;
     67   if (hasUnicode(string)) {
     68     var strSymbols = stringToArray(string);
     69     strLength = strSymbols.length;
     70   }
     71   if (length >= strLength) {
     72     return string;
     73   }
     74   var end = length - stringSize(omission);
     75   if (end < 1) {
     76     return omission;
     77   }
     78   var result = strSymbols
     79     ? castSlice(strSymbols, 0, end).join('')
     80     : string.slice(0, end);
     81 
     82   if (separator === undefined) {
     83     return result + omission;
     84   }
     85   if (strSymbols) {
     86     end += (result.length - end);
     87   }
     88   if (isRegExp(separator)) {
     89     if (string.slice(end).search(separator)) {
     90       var match,
     91           substring = result;
     92 
     93       if (!separator.global) {
     94         separator = RegExp(separator.source, toString(reFlags.exec(separator)) + 'g');
     95       }
     96       separator.lastIndex = 0;
     97       while ((match = separator.exec(substring))) {
     98         var newEnd = match.index;
     99       }
    100       result = result.slice(0, newEnd === undefined ? end : newEnd);
    101     }
    102   } else if (string.indexOf(baseToString(separator), end) != end) {
    103     var index = result.lastIndexOf(separator);
    104     if (index > -1) {
    105       result = result.slice(0, index);
    106     }
    107   }
    108   return result + omission;
    109 }
    110 
    111 module.exports = truncate;