test: avoid out-of-bounds getinfo parsing #35539

Avoid a possible IndexError: list index out of range

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For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/35539.

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Is this a bugfix? If so, how is this bug triggered?

Is this a bugfix? If so, how is this bug triggered?

Hello sir,

The old condition checks line_idx < len(lines), but then accesses lines[line_idx + 1], which raises IndexError.

while line_idx + 1 < len(lines) and lines[line_idx + 1] != '' is a safer condition to check.

It can be triggered if the helper receives truncated or malformed bitcoin-cli -getinfo output where Balances is the final line.

Thank you!! Jay

We want the test to fail when the output is corrupt, so the prior code is correct

Thx, but LLM output is not accepted if the author can not properly explain, test or could have written the change themselves.

The bottleneck in this project has always been review and testing, not writing code. Development here is intentionally conservative and slow, and reviewer attention is the scarcest resource we have. LLMs have made this worse, anyone can now prompt them and post their output as PRs. There is an infinite amount plausible looking "improvements" for LLMs to suggest and work on.

Unless we fully trust LLMs to both write and review code, humans still have to spend time understanding the proposed changes, which incurs a non-zero cost for every opened PR.

I understand that contributing to this project can be intimidating, and using LLMs may seem tempting, but it really creates more issues for this project than it solves. The best way to help this project, is to review and test changes. You can use LLMs for this, but you shouldn't solely rely on them, or just post their output.

I am asking you to reconsider whether it's something you genuinely think the project should pursue, independent of what your LLM suggested.

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