Feature request #78: Expose function to find the hash method of a signature

I've not used the name "find_method_hash" suggested in #78, as it's a bit
vague. It's ok-ish for a private function `_find_method_hash`, but I
thought `find_signature_hash` would be more descriptive.

1 files changed, 9 insertions, 1 deletions

diff --git a/tests/test_pkcs1.py b/tests/test_pkcs1.py
index 2116284..a8afea7 100644
--- a/tests/test_pkcs1.py
+++ b/tests/test_pkcs1.py
@@ -76,7 +76,15 @@ class SignatureTest(unittest.TestCase):
         message = b'je moeder'
         signature = pkcs1.sign(message, self.priv, 'SHA-256')
 
-        self.assertTrue(pkcs1.verify(message, signature, self.pub))
+        self.assertEqual('SHA-256', pkcs1.verify(message, signature, self.pub))
+
+    def test_find_signature_hash(self):
+        """Test happy flow of sign and find_signature_hash"""
+
+        message = b'je moeder'
+        signature = pkcs1.sign(message, self.priv, 'SHA-256')
+
+        self.assertEqual('SHA-256', pkcs1.find_signature_hash(signature, self.pub))
 
     def test_alter_message(self):
         """Altering the message should let the verification fail."""