test: Cover AddrMan add edge cases #36229

Add focused unit tests for meaningful AddrMan::Add edge cases without changing production behavior.

The tests cover:

empty and rejected batches; mixed batches containing rejected and valid addresses; duplicate records within a batch; rejection of unroutable addresses; timestamp penalty clamping at zero; one-hour and 24-hour timestamp update boundaries using a deterministic fake clock; preservation of source-derived bucket placement across newer announcements; preservation of tried-table membership for newer records; and service flags being merged without removing previously known capabilities.

<!--e57a25ab6845829454e8d69fc972939a-->

The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

<!--006a51241073e994b41acfe9ec718e94-->

Code Coverage & Benchmarks

For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/36229.

<!--021abf342d371248e50ceaed478a90ca-->

Reviews

See the guideline and AI policy for information on the review process. A summary of reviews will appear here.

<!--5faf32d7da4f0f540f40219e4f7537a3-->

LLM Linter (✨ experimental)

Possible places where named args for integral literals may be used (e.g. func(x, /*named_arg=*/0) in C++, and func(x, named_arg=0) in Python):

• addrman->GetAddr(0, 0, std::nullopt, false) in src/test/addrman_tests.cpp

^{2026-09-12 05:47:34}

corecheck doesn't show any gained coverage, can you tell us what these edge cases are addressing in practice? any mutation?

are you still wokring on this or can it be closed?

<!--85328a0da195eb286784d51f73fa0af9-->

🚧 At least one of the CI tasks failed. _{Task NetBSD Cross: https://github.com/bitcoin/bitcoin/actions/runs/34676473518/job/105615469089} _{LLM reason (✨ experimental): CI failed due to a build error: addrman_tests.cpp could not compile because CAddress was constructed with a uint64_t instead of the expected ServiceFlags argument (type mismatch).}

<details><summary>Hints</summary>

Try to run the tests locally, according to the documentation. However, a CI failure may still happen due to a number of reasons, for example:

• Possibly due to a silent merge conflict (the changes in this pull request being incompatible with the current code in the target branch). If so, make sure to rebase on the latest commit of the target branch.

• A sanitizer issue, which can only be found by compiling with the sanitizer and running the affected test.

• An intermittent issue.

Leave a comment here, if you need help tracking down a confusing failure.

</details>

Probably ai slop that doesn't even compile and the llm bot is now offline