The Tor Browser / file revision

 var btoa;

 function test_derive(cryptoSvc) {

   // Extracted from test_utils_deriveKey.

   let pp = "secret phrase";

   let salt = "RE5YUHpQcGl3bg==";   // btoa("DNXPzPpiwn")

   // 16-byte, extract key data.

   let k = cryptoSvc.deriveKeyFromPassphrase(pp, salt, 16);

   do_check_eq(16, k.length);

   do_check_eq(btoa(k), "d2zG0d2cBfXnRwMUGyMwyg==");

   // Test different key lengths.

   k = cryptoSvc.deriveKeyFromPassphrase(pp, salt, 32);

   do_check_eq(32, k.length);

   let encKey = btoa(k);

   // Test via encryption.

   let iv = cryptoSvc.generateRandomIV();

   do_check_eq(cryptoSvc.decrypt(cryptoSvc.encrypt("bacon", encKey, iv), encKey, iv), "bacon");

   // Test default length (32).

   k = cryptoSvc.deriveKeyFromPassphrase(pp, salt, null);

   do_check_eq(32, k.length);

   do_check_eq(encKey, btoa(k));

 }

 function run_test() {

   let cryptoSvc;

   try {

     let backstagePass = Components.utils.import("resource://services-crypto/WeaveCrypto.js");

     btoa = backstagePass.btoa;

   } catch (ex) {

     _("Aborting test: no WeaveCrypto.js.");

     return;

   }

   test_derive(new WeaveCrypto());

 }