feat: Add __notes__ support (#3620)

* Add support for add_note()

* Ignore non-str notes

* minor tweaks

---------

Co-authored-by: Arjen Nienhuis <[email protected]>

Author: szokeasaurusrex

Diff for: sentry_sdk/utils.py

@@ -713,11 +713,21 @@ def get_errno(exc_value):
 
 def get_error_message(exc_value):
     # type: (Optional[BaseException]) -> str
-    return (
+    message = (
         getattr(exc_value, "message", "")
         or getattr(exc_value, "detail", "")
         or safe_str(exc_value)
-    )
+    )  # type: str
+
+    # __notes__ should be a list of strings when notes are added
+    # via add_note, but can be anything else if __notes__ is set
+    # directly. We only support strings in __notes__, since that
+    # is the correct use.
+    notes = getattr(exc_value, "__notes__", None)  # type: object
+    if isinstance(notes, list) and len(notes) > 0:
+        message += "\n" + "\n".join(note for note in notes if isinstance(note, str))
+
+    return message
 
 
 def single_exception_from_error_tuple(

Diff for: tests/test_basics.py

@@ -999,3 +999,46 @@ def test_hub_current_deprecation_warning():
 def test_hub_main_deprecation_warnings():
     with pytest.warns(sentry_sdk.hub.SentryHubDeprecationWarning):
         Hub.main
+
+
+@pytest.mark.skipif(sys.version_info < (3, 11), reason="add_note() not supported")
+def test_notes(sentry_init, capture_events):
+    sentry_init()
+    events = capture_events()
+    try:
+        e = ValueError("aha!")
+        e.add_note("Test 123")
+        e.add_note("another note")
+        raise e
+    except Exception:
+        capture_exception()
+
+    (event,) = events
+
+    assert event["exception"]["values"][0]["value"] == "aha!\nTest 123\nanother note"
+
+
+@pytest.mark.skipif(sys.version_info < (3, 11), reason="add_note() not supported")
+def test_notes_safe_str(sentry_init, capture_events):
+    class Note2:
+        def __repr__(self):
+            raise TypeError
+
+        def __str__(self):
+            raise TypeError
+
+    sentry_init()
+    events = capture_events()
+    try:
+        e = ValueError("aha!")
+        e.add_note("note 1")
+        e.__notes__.append(Note2())  # type: ignore
+        e.add_note("note 3")
+        e.__notes__.append(2)  # type: ignore
+        raise e
+    except Exception:
+        capture_exception()
+
+    (event,) = events
+
+    assert event["exception"]["values"][0]["value"] == "aha!\nnote 1\nnote 3"