refactor(isDate): add strictMode and prevent mixed delimiters

README.md

@@ -97,7 +97,7 @@ Validator                               | Description
 **isCreditCard(str)**                   | check if the string is a credit card.
 **isCurrency(str [, options])**            | check if the string is a valid currency amount.<br/><br/>`options` is an object which defaults to `{symbol: '$', require_symbol: false, allow_space_after_symbol: false, symbol_after_digits: false, allow_negatives: true, parens_for_negatives: false, negative_sign_before_digits: false, negative_sign_after_digits: false, allow_negative_sign_placeholder: false, thousands_separator: ',', decimal_separator: '.', allow_decimal: true, require_decimal: false, digits_after_decimal: [2], allow_space_after_digits: false}`.<br/>**Note:** The array `digits_after_decimal` is filled with the exact number of digits allowed not a range, for example a range 1 to 3 will be given as [1, 2, 3].
 **isDataURI(str)**                      | check if the string is a [data uri format](https://developer.mozilla.org/en-US/docs/Web/HTTP/data_URIs).
-**isDate(input [, format])**          | Check if the input is a valid date. e.g. [`2002-07-15`, new Date()].<br/><br/>`format` is a string and defaults to `YYYY/MM/DD`
+**isDate(input [, options])**          | Check if the input is a valid date. e.g. [`2002-07-15`, new Date()].<br/><br/> `options` is an object which can contain the keys `format`, `strictMode` and/or `delimiters`<br/><br/>`format` is a string and defaults to `YYYY/MM/DD`.<br/><br/>`strictMode` is a boolean and defaults to `false`. If `strictMode` is set to true, the validator will reject inputs different from `format`.<br/><br/> `delimiters` is an array of allowed date delimiters and defaults to `['/', '-']`.
 **isDecimal(str [, options])**             | check if the string represents a decimal number, such as 0.1, .3, 1.1, 1.00003, 4.0, etc.<br/><br/>`options` is an object which defaults to `{force_decimal: false, decimal_digits: '1,', locale: 'en-US'}`<br/><br/>`locale` determine the decimal separator and is one of `['ar', 'ar-AE', 'ar-BH', 'ar-DZ', 'ar-EG', 'ar-IQ', 'ar-JO', 'ar-KW', 'ar-LB', 'ar-LY', 'ar-MA', 'ar-QA', 'ar-QM', 'ar-SA', 'ar-SD', 'ar-SY', 'ar-TN', 'ar-YE', 'bg-BG', 'cs-CZ', 'da-DK', 'de-DE', 'en-AU', 'en-GB', 'en-HK', 'en-IN', 'en-NZ', 'en-US', 'en-ZA', 'en-ZM', 'es-ES', 'fr-FR', 'hu-HU', 'it-IT', 'ku-IQ', nb-NO', 'nl-NL', 'nn-NO', 'pl-PL', 'pt-BR', 'pt-PT', 'ru-RU', 'sl-SI', 'sr-RS', 'sr-RS@latin', 'sv-SE', 'tr-TR', 'uk-UA']`.<br/>**Note:** `decimal_digits` is given as a range like '1,3', a specific value like '3' or min like '1,'.
 **isDivisibleBy(str, number)**          | check if the string is a number that's divisible by another.
 **isEAN(str)**                          | check if the string is an EAN (European Article Number).

src/lib/isDate.js

@@ -1,3 +1,11 @@
+import merge from './util/merge';
+
+const default_date_options = {
+  format: 'YYYY/MM/DD',
+  delimiters: ['/', '-'],
+  strictMode: false,
+};
+
 function isValidFormat(format) {
   return /(^(y{4}|y{2})[\/-](m{1,2})[\/-](d{1,2})$)|(^(m{1,2})[\/-](d{1,2})[\/-]((y{4}|y{2})$))|(^(d{1,2})[\/-](m{1,2})[\/-]((y{4}|y{2})$))/gi.test(format);
 }
@@ -13,11 +21,23 @@ function zip(date, format) {
   return zippedArr;
 }
 
-export default function isDate(input, format = 'YYYY/MM/DD') {
-  if (typeof input === 'string' && isValidFormat(format)) {
-    const splitter = /[-/]/,
-      dateAndFormat = zip(input.split(splitter), format.toLowerCase().split(splitter)),
-      dateObj = {};
+export default function isDate(input, options) {
+  if (typeof options === 'string') { // Allow backward compatbility for old format isDate(input [, format])
+    options = merge({ format: options }, default_date_options);
+  } else {
+    options = merge(options, default_date_options);
+  }
+  if (typeof input === 'string' && isValidFormat(options.format)) {
+    const formatDelimiter = options.delimiters
+      .find(delimiter => options.format.indexOf(delimiter) !== -1);
+    const dateDelimiter = options.strictMode
+      ? formatDelimiter
+      : options.delimiters.find(delimiter => input.indexOf(delimiter) !== -1);
+    const dateAndFormat = zip(
+      input.split(dateDelimiter),
+      options.format.toLowerCase().split(formatDelimiter)
+    );
+    const dateObj = {};
 
     for (const [dateWord, formatWord] of dateAndFormat) {
       if (dateWord.length !== formatWord.length) {
@@ -30,5 +50,9 @@ export default function isDate(input, format = 'YYYY/MM/DD') {
     return new Date(`${dateObj.m}/${dateObj.d}/${dateObj.y}`).getDate() === +dateObj.d;
   }
 
-  return Object.prototype.toString.call(input) === '[object Date]' && isFinite(input);
+  if (!options.strictMode) {
+    return Object.prototype.toString.call(input) === '[object Date]' && isFinite(input);
+  }
+
+  return false;
 }

test/validators.js

@@ -8751,11 +8751,12 @@ describe('Validators', () => {
         '2020-02-30', // invalid date
         '2019-02-29', // non-leap year
         '2020-04-31', // invalid date
+        '2020/03-15', // mixed delimiter
       ],
     });
     test({
       validator: 'isDate',
-      args: ['DD/MM/YYYY'],
+      args: ['DD/MM/YYYY'], // old format for backward compatibility
       valid: [
         '15-07-2002',
         '15/07/2002',
@@ -8765,23 +8766,40 @@ describe('Validators', () => {
         '15-7-2002',
         '15/7/02',
         '15-7-02',
+        '15-07/2002',
       ],
     });
     test({
       validator: 'isDate',
-      args: ['DD/MM/YY'],
+      args: [{ format: 'DD/MM/YYYY' }],
+      valid: [
+        '15-07-2002',
+        '15/07/2002',
+      ],
+      invalid: [
+        '15/7/2002',
+        '15-7-2002',
+        '15/7/02',
+        '15-7-02',
+        '15-07/2002',
+      ],
+    });
+    test({
+      validator: 'isDate',
+      args: [{ format: 'DD/MM/YY' }],
       valid: [
         '15-07-02',
         '15/07/02',
       ],
       invalid: [
         '15/7/2002',
         '15-7-2002',
+        '15/07-02',
       ],
     });
     test({
       validator: 'isDate',
-      args: ['D/M/YY'],
+      args: [{ format: 'D/M/YY' }],
       valid: [
         '5-7-02',
         '5/7/02',
@@ -8790,6 +8808,65 @@ describe('Validators', () => {
         '5/07/02',
         '15/7/02',
         '15-7-02',
+        '5/7-02',
+      ],
+    });
+    test({
+      validator: 'isDate',
+      args: [{ format: 'DD/MM/YYYY', strictMode: true }],
+      valid: [
+        '15/07/2002',
+      ],
+      invalid: [
+        '15-07-2002',
+        '15/7/2002',
+        '15-7-2002',
+        '15/7/02',
+        '15-7-02',
+        '15-07/2002',
+      ],
+    });
+    test({
+      validator: 'isDate',
+      args: [{ strictMode: true }],
+      valid: [
+        '2020/01/15',
+        '2014/02/15',
+        '2014/03/15',
+        '2020/02/29',
+      ],
+      invalid: [
+        '2014-02-15',
+        '2020-02-29',
+        '15-07/2002',
+        new Date(),
+        new Date([2014, 2, 15]),
+        new Date('2014-03-15'),
+      ],
+    });
+    test({
+      validator: 'isDate',
+      args: [{ delimiters: ['/', ' '] }],
+      valid: [
+        new Date(),
+        new Date([2014, 2, 15]),
+        new Date('2014-03-15'),
+        '2020/02/29',
+        '2020 02 29',
+      ],
+      invalid: [
+        '2020-02-29',
+        '',
+        '15072002',
+        null,
+        undefined,
+        { year: 2002, month: 7, day: 15 },
+        42,
+        { toString() { return '[object Date]'; } },
+        '2020/02/30',
+        '2019/02/29',
+        '2020/04/31',
+        '2020/03-15',
       ],
     });
   });