perf(jid): compare structured JID attributes without rendering them

[jlucaso1]

A decoded JID attribute is kept structured as ValueRef::Jid. Comparing it to a literal via v.as_str() == SERVER_JID throws that away: as_str() renders the JID into an owned String purely to be compared and dropped. ValueRef already implements PartialEq<str>, which walks the display form against the needle without building it.

Applied to the server-origin checks in pair.rs, passkey/flow.rs (×2) and device-notification handling, plus NodeFilter's attribute match.

Equivalence

Two of these gate whether a stanza is honored at all ("only honor a server request"), so this is not a place to assume the two forms agree — I checked. comparing_a_jid_value_matches_comparing_its_rendered_form asserts v == needle matches v.as_str() == needle across user, device, agent, group, lid and broadcast shapes, for both the Jid and String variants, and specifically for the server-only JID (s.whatsapp.net, empty user) — which is the shape those checks actually compare against, and the one the fast parser declines to handle.

Deliberately not included

The same sweep also proposed node.get_attr("from").and_then(|v| v.as_str().parse().ok()) → v.to_jid() for ServerAck. I left that out: measured against the old form, it is not equivalent. Display omits the agent for servers where renders_agent() is false, so stringify-then-reparse silently drops it while to_jid() preserves it:

12345.6@hosted.lid
  old (stringify+parse): agent = 0
  new (to_jid):          agent = 6

to_jid() is arguably the more faithful reading — the agent came off the wire — but it changes an observable field of a published event, and Event payloads are a frozen API. That belongs in its own change with its own justification, not smuggled into a perf PR.

Found by a two-model performance sweep (Claude Opus 5 and Codex gpt-5.6-sol). Codex measured the comparison shortcut in isolation; note these are low-frequency control-flow paths, so the aggregate gain is modest — the durable value is not undoing the structured representation the decoder went to the trouble of keeping.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI (base), Organization UI (inherited)

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: 44218f64-94fa-49cd-b125-920f2e6b3371

📥 Commits

Reviewing files that changed from the base of the PR and between 83e7b89 and 887694a.

📒 Files selected for processing (5)

• src/client.rs
• src/handlers/notification/device.rs
• src/pair.rs
• src/passkey/flow.rs
• wacore/binary/src/node.rs

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📝 Walkthrough

Summary by CodeRabbit

• Bug Fixes

  • Improved validation of server-targeted notifications and incoming requests.
  • Ensured attribute matching works consistently for JIDs, strings, and invalid values.

• Tests

  • Added coverage for comparing node values directly with string values, including server-only and invalid JIDs.

Walkthrough

The PR replaces redundant string conversions with direct ValueRef comparisons in node filtering and server-JID validation, and adds tests covering JID and string equality behavior.

Changes

ValueRef matching updates

Layer / File(s)	Summary
Direct attribute and server-JID comparisons src/client.rs, src/handlers/notification/device.rs, src/pair.rs, src/passkey/flow.rs	Node filtering and notification, IQ, and passkey validation compare attribute values directly against expected strings or SERVER_JID.
ValueRef equality tests wacore/binary/src/node.rs	Tests cover ValueRef::Jid and ValueRef::String comparisons, including server-only JIDs and invalid inputs.

Estimated code review effort: 2 (Simple) | ~10 minutes

Possibly related PRs

• oxidezap/whatsapp-rust#249: Adjusts similar SERVER_JID attribute comparisons.
• oxidezap/whatsapp-rust#307: Updates NodeFilter::matches comparison behavior.
• oxidezap/whatsapp-rust#514: Introduces related NodeStr and direct comparison semantics.

Suggested labels: performance

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main optimization: comparing structured JID attributes without rendering them.
Description check	✅ Passed	The description matches the changeset and explains the JID comparison optimization and related test coverage.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch perf/valueref-jid-no-stringify

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