Improve feedback/information with "broken repr"

[blueyed]

If the __repr__ of a local object fails, it gets reported as "<broken repr>":

sentry-python/sentry_sdk/utils.py

Lines 416 to 451 in d7cf16c

	if PY2:
	def safe_repr(value):
	# type: (Any) -> str
	try:
	rv = repr(value).decode("utf-8", "replace")
	# At this point `rv` contains a bunch of literal escape codes, like
	# this (exaggerated example):
	#
	# u"\\x2f"
	#
	# But we want to show this string as:
	#
	# u"/"
	try:
	# unicode-escape does this job, but can only decode latin1. So we
	# attempt to encode in latin1.
	return rv.encode("latin1").decode("unicode-escape")
	except Exception:
	# Since usually strings aren't latin1 this can break. In those
	# cases we just give up.
	return rv
	except Exception:
	# If e.g. the call to `repr` already fails
	return u"<broken repr>"
	else:
	def safe_repr(value):
	# type: (Any) -> str
	try:
	return repr(value)
	except Exception:
	return "<broken repr>"

It would be more helpful if it would include more information there, e.g. at least the class name of the exception.
It could also be something more sophisticated like:

def _try_repr_or_str(obj):
    try:
        return repr(obj)
    except (KeyboardInterrupt, SystemExit):
        raise
    except BaseException:
        return '{}("{}")'.format(type(obj).__name__, obj)


def _format_repr_exception(exc: BaseException, obj: Any) -> str:
    try:
        exc_info = _try_repr_or_str(exc)
    except (KeyboardInterrupt, SystemExit):
        raise
    except BaseException as exc:
        exc_info = "unpresentable exception ({})".format(_try_repr_or_str(exc))
    return "<[{} raised in repr()] {} object at 0x{:x}>".format(
        exc_info, type(obj).__name__, id(obj)
    )

(via https://github.com/blueyed/pytest/blob/8eb380425395332ffdf2cd42b8d7cf8ffab2ea2e/src/_pytest/_io/saferepr.py#L6-L24)

This would help with investigating why a repr is broken actually, e.g. with celery/py-amqp#361.

(slightly related: there was some related (still open) PR for raven-python about this already: getsentry/raven-python#1294)

[github-actions]

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But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[sl0thentr0py]

hi @blueyed, we released an undocumented feature def sentry_repr in #1322.
Could you try it out and see if it fixes your problem?

[github-actions]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀