[turnipdabeets]

💡 Motivation and Context

Follow-up to #938, from the review bot's comment.

PostHogQueue.flushIfOverThreshold() flushes early once fileQueue.byteCount reaches endpoint.maxBatchBytes (5 MiB for analytics). But PostHogFileBackedQueue only tracked byteCount when it had a disk byte cap (maxBytes, from maxQueueBytes), and only the AI endpoint sets one. For analytics byteCount stayed 0, so the early flush never fired, and large events waited for flushAt or the flush timer.

What changed:

• PostHogFileBackedQueue takes a new trackBytes flag. It tracks file sizes when trackBytes or maxBytes is set. Eviction still happens only when maxBytes is set, as before.
• PostHogQueue passes trackBytes: endpoint.maxBatchBytes != nil, so analytics counts bytes but still has no disk byte cap.

No new changeset: this is an unreleased 4.0 fix, and the existing .changeset/v4-capture-v1.md on #938 already describes the 5 MiB analytics batches.

💚 How did you test it?

• New test flushesAtByteLimit (Capture V1 queue suite): three ~2 MiB analytics events, flushAt = 100, queue not started (no timer), no manual flush. With the fix the queue drains. Without the fix it fails: queue.depth → 3, no requests sent after 10 s.
• New test tracksBytesWithoutLimit (file-backed queue alignment suite): byteCount is tracked with trackBytes and no maxBytes, survives a reload from disk, decreases on pop, and nothing is evicted.
• swift test --no-parallel -Xswiftc -DTESTING --filter 'PostHogQueueTest|PostHogCaptureV1|PostHogFileBackedQueue': 109 tests in 9 suites passed twice in a row. A third run had failures in FileBackedQueue Concurrency Tests, but only while another local session was running the same test bundle against the shared Application Support directory. That suite doesn't use byte tracking.
• make lint: no new warnings. Didn't run make buildSdk because xcpretty isn't installed locally.

📝 Checklist

• All commits are signed (see Commit signing)
• I reviewed the submitted code.
• I added tests to verify the changes.
• I updated the docs if needed.
• No breaking change or entry added to the changelog.

🤖 Agent context

Autonomy: Human-driven (agent-assisted)

Built with Claude Code. I used a separate trackBytes flag instead of giving analytics a maxQueueBytes cap, so analytics doesn't get byte-based eviction it never had.

🤖 Generated with Claude Code

[dustinbyrne]

Byte tracking remains separate from eviction, and the added analytics-factory and accounting regression tests cover the intended behavior. No actionable findings.

AI-assisted review.