Type the server's NoLeaderException instead of a misspelled key

ravendb/exceptions/cluster.py

@@ -1,9 +1,13 @@
 from ravendb.exceptions.raven_exceptions import RavenException
 
 
-class NoLoaderException(RavenException):
+class NoLeaderException(RavenException):
     pass
 
 
+# The name this class shipped under.
+NoLoaderException = NoLeaderException
+
+
 class NodeIsPassiveException(RavenException):
     pass

ravendb/exceptions/exception_dispatcher.py

@@ -4,7 +4,7 @@
 import os
 from datetime import timedelta
 
-from ravendb.exceptions.cluster import NodeIsPassiveException, NoLoaderException
+from ravendb.exceptions.cluster import NodeIsPassiveException, NoLeaderException
 from ravendb.exceptions.commercial import LicenseLimitException
 from ravendb.exceptions.documents import DocumentConflictException, DocumentDoesNotExistException
 from ravendb.exceptions.documents.bulkinsert import BulkInsertAbortedException, BulkInsertProtocolViolationException
@@ -62,7 +62,7 @@
     "ReplicationHubNotFoundException": ReplicationHubNotFoundException,
     # cluster
     "NodeIsPassiveException": NodeIsPassiveException,
-    "NoLoaderException": NoLoaderException,
+    "NoLeaderException": NoLeaderException,
     # commercial
     "LicenseLimitException": LicenseLimitException,
 }

ravendb/tests/issue_tests/test_exception_dispatcher.py

@@ -0,0 +1,34 @@
+import http
+from unittest import TestCase
+
+from ravendb.exceptions.cluster import NoLeaderException, NoLoaderException
+from ravendb.exceptions.exception_dispatcher import ExceptionDispatcher
+from ravendb.exceptions.raven_exceptions import RavenException
+
+
+def _dispatch(type_as_string: str) -> RavenException:
+    schema = ExceptionDispatcher.ExceptionSchema(
+        url="http://localhost:8080",
+        object_type=type_as_string,
+        message="no leader",
+        error="no leader",
+    )
+    schema.type = type_as_string
+    return ExceptionDispatcher.get(schema, http.HTTPStatus.INTERNAL_SERVER_ERROR)
+
+
+class TestExceptionDispatcher(TestCase):
+    def test_no_leader_from_the_server_is_typed(self):
+        # The map was keyed on "NoLoaderException", which the server never sends, so a real
+        # no-leader failure arrived as a plain RavenException.
+        exception = _dispatch("Raven.Client.Exceptions.Cluster.NoLeaderException")
+
+        self.assertIsInstance(exception, NoLeaderException)
+
+    def test_the_old_misspelled_name_is_still_importable(self):
+        self.assertIs(NoLeaderException, NoLoaderException)
+
+    def test_an_unknown_type_stays_a_raven_exception(self):
+        exception = _dispatch("Raven.Client.Exceptions.Cluster.SomethingElseException")
+
+        self.assertIs(RavenException, type(exception))