function makePhrase.js.html

function makePhrase.js.html

<script language="JavaScript">

  function isArrayOrObject(val) {
    return val instanceof Array || val instanceof Object;
  }

  function isStringOrWrapper(val) {
    return typeof val === 'string' || val instanceof String;
  }

  /**
   * If obj arg is a array after evaluation, returns the strPlural arg, otherwise returns strSingle arg.
   *
   * Evaluates checking:
   * - if obj arg is undefined, null, empty string, or only one element, or is not a array or an object.
   * - apply split function, if strToSplit arg is present
   * */
  function makePhrase(obj, strSingle, strPlural, strToSplit) {
    if (!obj?.length || obj.length === 1) {
      return strSingle;
    } else if (isArrayOrObject(obj) && obj.length > 1) {
      return strPlural;
    } else if (isStringOrWrapper(obj) && !!strToSplit && obj.split(strToSplit)?.length > 1) {
      return strPlural;
    } else {
      return strSingle;
    }
  }


  /*--- TESTS: -------------------------------------------------------------*/

  function isJSONStr(str) {
    try {
      return (JSON.parse(str) && !!str);
    } catch (e) {
      return false;
    }
  }

  /**
   * Testado com:
   * - [{"aField": 1}, {"aField": 2}]
   * - [{"aField": 1}]
   * - {"aField": 1}
   * - vazio
   * - null
   * - [1,2,3]
   * - strings quaisquer com e sem espaço
   * - strings quaisquer com algum split a ser feito
   */
  let testValue = window.prompt("informe um objeto para teste: ", '[{"aField": 1}, {"aField": 2}]');
  let strToSplit = window.prompt("informe a string para o split: ", "");
  if (isJSONStr(testValue)) {
    testValue = JSON.parse(testValue);
  }
  window.alert(makePhrase(testValue, "single phrase!", "plural phrase!", strToSplit));

</script>