perf: avoid app frame query in private AX fallback

[thymikee]

Summary

Use the private AX root frame as the fallback viewport before querying app.frame. This avoids an avoidable public XCTest query inside the private AX recovery path, which can record a failure and force the runner to relaunch after an otherwise successful fallback snapshot.

Scope: 1 Swift runner file. This is stacked on fix/ios-snapshot-private-ax-recovery.

Validation

Ran pnpm build:xcuitest; XCTest runner build passed. Prior physical-device probing on thymikee-iphone showed Bluesky private AX fallback warm snapshots avoiding runner restart when the private AX root frame path is used.

[github-actions]

Size Report

Metric	Base	Current	Diff
JS raw	1.3 MB	1.3 MB	+4 B
JS gzip	434.5 kB	434.4 kB	-8 B
npm tarball	572.7 kB	572.7 kB	-29 B
npm unpacked	1.9 MB	1.9 MB	-85 B

Startup median (7 runs, lower is better):

Scenario	Base	Current	Diff
CLI --version	25.8 ms	26.3 ms	+0.6 ms
CLI --help	45.5 ms	45.7 ms	+0.2 ms

Top changed chunks:

Chunk	Raw diff	Gzip diff
dist/src/2948.js	+4 B	-8 B

[thymikee]

Review — perf: avoid app frame query in private AX fallback

🤖 Automated review (Claude Code). Stacked on fix/ios-snapshot-private-ax-recovery.

Overview
In the private-AX fallback, use the private AX root frame as the primary viewport and only call safeSnapshotViewport(app:) (which queries app.frame — a public XCTest query that can record a failure and force a runner relaunch) when the root frame is empty. This inverts the previous precedence (app frame primary, root frame fallback).

Looks good

• Minimal and well-scoped; it directly removes the avoidable public query on the success path, matching the stated goal and the validated Bluesky physical-device behavior.

Two small notes

1. Stale comment. The leading comment ("If the app frame is unavailable, the private root's own frame is the reliable screen rect here") now describes the old precedence — the new code uses rootFrame unconditionally when non-empty and never consults app.frame first. Suggest: "Prefer the private root's own frame as the screen rect; fall back to the public app-frame query only when the root frame is empty."
2. Precedence inversion — sanity-check beyond Bluesky. Previously app.frame won when both were valid; now a non-empty rootFrame always wins. If any app's private AX root frame is a sub-region rather than the full screen, downstream viewport inference shifts. Validated on Bluesky, so fine to ship — just flagging the inversion for other deep RN apps.

[thymikee]

Addressed the stale comment: it now describes the new precedence explicitly, preferring the private AX root frame and falling back to the public app-frame query only when the root frame is empty. The precedence inversion is intentional for this PR; the fallback remains sparse-checked and quality-stamped by the existing capture plan.

[github-actions]

PR Preview Action v1.8.1
Preview removed because the pull request was closed.
2026-06-25 16:56 UTC