fix traces in .throws assertions

[dflupu]

Fixes #1372

[novemberborn]

The code's great!

The code snippet is no longer showing the assertion though. It shows the error being constructed. I think we might have to track both the assertion and the error stack and use them appropriately.

It's getting late here so let me know if you want some pointers. You seem to be pretty good at finding your way around the codebase though!

[dflupu]

My thought process was along the lines of: whenever an error is thrown during an ava test, the stack trace always shows where the error was constructed, with the assertion being at the bottom of the trace. If an error is thrown inside a .notThrows, I think that it is fair to treat it as any other unexpected error. Same with errors of different types inside a .throws.

Do you disagree? Is there any situation in which both traces would be required?

[novemberborn]

The stack traces shown are fine, but we also show where the assertion took place. Compare:

I think we should show the code snippet for t.throws() not new Error().

[dflupu]

I've updated the PR. The output should be closer to what you had in mind.
Let me know if you see a cleaner way of implementing this. Note that the trace created in the AssertionError constructor doesn't always contain the frame where the assertion was made.

[novemberborn]

My thinking was we'd store two different "stack" properties. One to determine the source location, the other belonging to thrown errors / rejection reasons. The stack extracted in trySerializeError would first use the latter, and if missing fall back to the former. I think that'll work out better than setting a boolean flag.

[novemberborn]

Thanks @dflupu!

[sindresorhus]

@dflupu Thank you!

You need to submit the PR URL to IssueHunt to claim the bounty ;)

[dflupu]

@sindresorhus No worries, I'll be sure to submit it. I prefer to wait until the PR is accepted/merged because it feels like bad manners to submit before. Might be mostly because of the useless bot post when you do submit.