strictly compare for NSNull values #1138

[tshedor]

Goal

When attaching a custom stack trace, the stack trace types is sometimes an NSNull object. This causes an unhandled error detailed in #1138

Design

This strictly checks for nil and NSNull values instead of exclusively nil values. It's a bit of a hack.

The unhandled errors are universally reported immediately after app start, which would indicate that custom stack trace errors that are stored before the next app launch (like in the event of a simultaneous OOM) are not stored within BSGKeyStacktrace. I'm a little lost in this code base so please forgive me not going deeper than ensuring NSNull values aren't iterated.

Changeset

The comparison for trace in BugsnagError.m changed from != nil to !(trace == nil || trace == NSNull).

Testing

This bug has been difficult to reproduce, but the change is additive and so I believe it's a low risk solution with substantial gain (the gain being the Bugsnag error collector does not produce errors itself).

[nickdowell]

Hi @tshedor I'm closing this as we've addressed the issue with #1143

Thanks for looking into it 👍

[tshedor]

Thanks @nickdowell fo the quick response, I appreciate it