Update self-tests for new methods

lib/rbnacl/self_test.rb

@@ -42,16 +42,12 @@ def box_common_test(box)
         #:nocov:
       end
 
-      begin
-        passed         = false
-        corrupt_ct     = ciphertext.dup
-        corrupt_ct[23] = ' '
-        corrupt_ct
-        box.decrypt(nonce, corrupt_ct)
-      rescue CryptoError
-        passed = true
-      ensure
-        passed or raise SelfTestFailure, "failed to detect corrupt ciphertext"
+      corrupt_ct     = ciphertext.dup
+      corrupt_ct[23] = ' '
+      if box.decrypt!(nonce, corrupt_ct)
+        #:nocov:
+        raise SelfTestFailure, "failed to detect corrupt ciphertext"
+        #:nocov:
       end
     end
 
@@ -82,7 +78,7 @@ def digital_signature_test
 
       bad_signature = signature[0,63] + '0'
 
-      unless verify_key.verify(bad_signature, message) == false
+      unless verify_key.verify!(bad_signature, message) == false
         #:nocov:
         raise SelfTestFailure, "failed to detect an invalid signature"
         #:nocov:
@@ -111,13 +107,13 @@ def hmac_test(klass, tag)
         #:nocov:
       end
 
-      unless authenticator.verify(vector(tag), message)
+      unless authenticator.verify!(vector(tag), message)
         #:nocov:
         raise SelfTestFailure, "#{klass} failed to verify correct authentication tag"
         #:nocov:
       end
 
-      if authenticator.verify(vector(tag), message + ' ')
+      if authenticator.verify!(vector(tag), message + ' ')
         #:nocov:
         raise SelfTestFailure, "#{klass} failed to detect invalid authentication tag"
         #:nocov: