feat(isPostalCode): add validation for Bangladeshi (BD) postal codes

Author: tanvirrb

src/lib/isPostalCode.js

@@ -12,6 +12,7 @@ const patterns = {
   AU: fourDigit,
   AZ: /^AZ\d{4}$/,
   BA: /^([7-8]\d{4}$)/,
+  BD: /^(?:[1-8]\d{3}|9[0-3]\d{2}|94[0-8]\d|949[0-9])$/,
   BE: fourDigit,
   BG: fourDigit,
   BR: /^\d{5}-?\d{3}$/,

test/validators.test.js

@@ -12982,6 +12982,22 @@ describe('Validators', () => {
           '11000',
         ],
       },
+      {
+        locale: 'BD',
+        valid: [
+          '1219',
+          '1231',
+          '2201',
+          '1532',
+          '1744',
+        ],
+        invalid: [
+          '9500',
+          '9999',
+          '9832',
+          '9782',
+        ],
+      },
     ];
 
     let allValid = [];