Add nik to indonesia

readme.md

@@ -937,6 +937,18 @@ echo $faker->siret; // 347 355 708 00224
 echo $faker->bankAccountNumber; // "HU09904437680048220079300783"
 ```
 
+### `Faker\Provider\id_ID\Person`
+
+```php
+<?php
+
+// Generates a random Nomor Induk Kependudukan (NIK)
+
+// first argument is gender, either Person::GENDER_MALE or Person::GENDER_FEMALE, if none specified random gender is used
+// second argument is birth date (DateTime object), if none specified, random birth date is used
+echo $faker->nik(); // "8522246001570940"
+```
+
 ### `Faker\Provider\it_IT\Company`
 
 ```php

src/Faker/Provider/id_ID/Person.php

@@ -253,4 +253,41 @@ public static function suffix()
     {
         return static::randomElement(static::$suffix);
     }
+
+    /**
+     * Generates Nomor Induk Kependudukan (NIK)
+     *
+     * @link https://en.wikipedia.org/wiki/National_identification_number#Indonesia
+     *
+     * @param null|string $gender
+     * @param null|\DateTime $birthDate
+     * @return string
+     */
+    public function nik($gender = null, $birthDate = null)
+    {
+        # generate first numbers (region data)
+        $nik = $this->generator->numerify('######');
+
+        if (!$birthDate) {
+            $birthDate = $this->generator->dateTimeBetween();
+        }
+
+        if (!$gender) {
+            $gender = $this->generator->randomElement(array(self::GENDER_MALE, self::GENDER_FEMALE));
+        }
+
+        # if gender is female, add 40 to days
+        if ($gender == self::GENDER_FEMALE) {
+            $nik .= $birthDate->format('d') + 40;
+        } else {
+            $nik .= $birthDate->format('d');
+        }
+
+        $nik .= $birthDate->format('my');
+
+        # add last random digits
+        $nik.= $this->generator->numerify('####');
+
+        return $nik;
+    }
 }