check country code too

src/lib/isBIC.js

@@ -1,9 +1,17 @@
 import assertString from './util/assertString';
+import { CountryCodes } from './isISO31661Alpha2';
 
 // https://en.wikipedia.org/wiki/ISO_9362
 const isBICReg = /^[A-Za-z]{6}[A-Za-z0-9]{2}([A-Za-z0-9]{3})?$/;
 
 export default function isBIC(str) {
   assertString(str);
+
+  // toUpperCase() should be removed when a new major version goes out that changes
+  // the regex to [A-Z] (per the spec).
+  if (CountryCodes.indexOf(str.slice(4, 6).toUpperCase()) < 0) {
+    return false;
+  }
+
   return isBICReg.test(str);
 }

src/lib/isISO31661Alpha2.js

@@ -1,5 +1,4 @@
 import assertString from './util/assertString';
-import includes from './util/includes';
 
 // from https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2
 const validISO31661Alpha2CountriesCodes = [
@@ -32,5 +31,7 @@ const validISO31661Alpha2CountriesCodes = [
 
 export default function isISO31661Alpha2(str) {
   assertString(str);
-  return includes(validISO31661Alpha2CountriesCodes, str.toUpperCase());
+  return validISO31661Alpha2CountriesCodes.indexOf(str.toUpperCase()) >= 0;
 }
+
+export const CountryCodes = validISO31661Alpha2CountriesCodes;