Address Lukas comments - add ed25519key_dict to test

Signed-off-by: Martin Vrachev <mvrachev@vmware.com>

tests/test_signer.py

@@ -21,7 +21,7 @@
 import securesystemslib.formats
 import securesystemslib.keys as KEYS
 from securesystemslib.signer import Signature, SSlibSigner
-import securesystemslib.exceptions as exceptions
+from securesystemslib.exceptions import FormatError, UnsupportedAlgorithmError
 
 class TestSSlibSigner(unittest.TestCase):
 
@@ -33,12 +33,11 @@ def setUpClass(cls):
     cls.DATA_STR = 'SOME DATA REQUIRING AUTHENTICITY.'
     cls.DATA = securesystemslib.formats.encode_canonical(cls.DATA_STR).encode(
         'utf-8')
-    cls.FORMAT_ERROR_MSG = 'securesystemslib.exceptions.FormatError was raised!' + \
-        '  Check object\'s format.'
 
 
   def test_sslib_sign(self):
-    for scheme_dict in [self.rsakey_dict, self.ecdsakey_dict]:
+    dicts_list = [self.rsakey_dict, self.ecdsakey_dict, self.ed25519key_dict]
+    for scheme_dict in dicts_list:
       # Test generation of signatures.
       sslib_signer = SSlibSigner(scheme_dict)
       sig_obj = sslib_signer.sign(self.DATA)
@@ -52,24 +51,25 @@ def test_sslib_sign(self):
       scheme_dict['keyval']['private'] = ''
       sslib_signer.key_dict = scheme_dict
 
-      with self.assertRaises(ValueError):
+      with self.assertRaises((ValueError, FormatError)):
         sslib_signer.sign(self.DATA)
 
       scheme_dict['keyval']['private'] = private
 
+      # Test for invalid signature scheme.
+      valid_scheme = scheme_dict['scheme']
+      scheme_dict['scheme'] = 'invalid_scheme'
+      sslib_signer = SSlibSigner(scheme_dict)
+
+      with self.assertRaises((UnsupportedAlgorithmError, FormatError)):
+          sslib_signer.sign(self.DATA)
+
+      scheme_dict['scheme'] = valid_scheme
+
       # Supplying an incorrect number of arguments.
       with self.assertRaises(TypeError):
         sslib_signer.sign()
 
-    # Test for invalid signature scheme.
-    valid_scheme = self.rsakey_dict['scheme']
-    self.rsakey_dict['scheme'] = 'invalid_scheme'
-    sslib_signer = SSlibSigner(self.rsakey_dict)
-
-    with self.assertRaises(exceptions.UnsupportedAlgorithmError):
-        sslib_signer.sign(self.DATA)
-
-    self.rsakey_dict['scheme'] = valid_scheme
 
 
   def test_signature_from_to_json(self):