ExceptionInfo.exception should be an exception

Author: woutdenolf

billiard/einfo.py

@@ -91,16 +91,24 @@ def __init__(self, tb, max_frames=DEFAULT_MAX_FRAMES, depth=0):
 class RemoteTraceback(Exception):
     def __init__(self, tb):
         self.tb = tb
+
     def __str__(self):
         return self.tb
 
-class ExceptionWithTraceback:
+
+class ExceptionWithTraceback(Exception):
     def __init__(self, exc, tb):
         self.exc = exc
         self.tb = '\n"""\n%s"""' % tb
+        super().__init__()
+
+    def __str__(self):
+        return self.tb
+
     def __reduce__(self):
         return rebuild_exc, (self.exc, self.tb)
 
+
 def rebuild_exc(exc, tb):
     exc.__cause__ = RemoteTraceback(tb)
     return exc

t/unit/test_einfo.py

@@ -0,0 +1,28 @@
+import pickle
+import logging
+from billiard.einfo import ExceptionInfo
+
+logger = logging.getLogger(__name__)
+
+
+def test_exception_info_log_before_pickle(caplog):
+    try:
+        raise RuntimeError("some message")
+    except Exception:
+        exception = ExceptionInfo().exception
+
+    logger.exception("failed", exc_info=exception)
+    assert ' raise RuntimeError("some message")' in caplog.text
+    assert "RuntimeError: some message" in caplog.text
+
+
+def test_exception_info_log_after_pickle(caplog):
+    try:
+        raise RuntimeError("some message")
+    except Exception:
+        exception = ExceptionInfo().exception
+        exception = pickle.loads(pickle.dumps(exception))
+
+    logger.exception("failed", exc_info=exception)
+    assert ' raise RuntimeError("some message")' in caplog.text
+    assert "RuntimeError: some message" in caplog.text