raise KeyError if key KeyIssuer is not found

Author: jschlyter

src/cryptojwt/key_jar.py

@@ -276,7 +276,10 @@ def __getitem__(self, issuer_id=''):
         :param issuer_id: The entity ID
         :return: A KeyIssuer instance
         """
-        return self._get_issuer(issuer_id)
+        _iss = self._get_issuer(issuer_id)
+        if _iss is None:
+            raise KeyError(issuer_id)
+        return _iss
 
     @deprecated_alias(issuer='issuer_id', owner='issuer_id')
     def __setitem__(self, issuer_id, key_issuer):

tests/test_04_key_jar.py

@@ -733,7 +733,8 @@ def test_get_wrong_owner():
     assert kj.get('sig', 'rsa') == []
 
     assert 'https://delphi.example.com' not in kj
-    assert kj['https://delphi.example.com'] == None
+    with pytest.raises(KeyError):
+        kj['https://delphi.example.com']
 
 
 def test_match_owner():