Audit Swiftui State Restoration

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name: audit-swiftui-state-restoration description: Audit macOS SwiftUI state restoration for correctness, current APIs, and production conventions. Use for that domain or as part of a full audit.

Bundled resource root

Let <swiftui-plugin-root> be the absolute plugin directory two levels above this SKILL.md. Resolve that path before running commands or opening shared references. When these instructions say swiftui-ctx, invoke <swiftui-plugin-root>/scripts/swiftui-ctx; do not assume the command is on PATH.

Audit SwiftUI State Restoration

AUDIT-ONLY · macOS-only · SwiftUI-only. Run this on a finished or in-progress macOS SwiftUI project to detect — and where certain, flag the fix for — every way scene/app state restoration and lightweight persistence goes wrong: @AppStorage↔@SceneStorage confusion, hand-rolled UserDefaults where a wrapper fits, tab/sidebar/detail selection that suffers relaunch amnesia, NavigationPath that is never persisted, custom types or oversized blobs in size-limited storage, dead deep links, and ungated restorationBehavior / focusedSceneValue. Findings are written to disk in the toolkit's unified schema. This is never a from-scratch persistence generator.

This is the toolkit's orphaned domain: @AppStorage (app-wide preferences) versus @SceneStorage (per-window UI state) is the single most-confused axis. The wrapper compiles either way — the defect is semantic, so READ before you report.

Boundary / seam note (stay in lane)

• SwiftData @Model design and @Query fetches belong to audit-swiftui-swiftdata. This skill owns the decision to move oversized scene/app storage out (sr-08) and emits cross_ref: audit-swiftui-swiftdata; it does not audit the model graph.
• Window/scene plumbing (WindowGroup/Window/MenuBarExtra activation, .defaultSize, .windowResizability, handlesExternalEvents as a scene matcher) belongs to audit-swiftui-scenes-windows. This skill owns the restoration of scene UI state and restorationBehavior; defer scene activation there with a cross_ref.
• Navigation structure (NavigationStack/NavigationSplitView columns, NavigationLink) belongs to audit-swiftui-navigation-toolbars. This skill owns persisting the NavigationPath/selection across relaunch (sr-05/06), not the navigation shape.
• @FocusedValue/focusedSceneValue command routing belongs to audit-swiftui-menus-commands; this skill flags only the focusedSceneValue availability floor (sr-11) and cross_refs the routing owner.

The state-restoration model (the load-bearing distinction)

1. @AppStorage = app-wide preference. One value shared by every window/scene — theme, default units, "show line numbers". Backed by UserDefaults.
2. @SceneStorage = per-window UI state. Restored per scene by the system — selected tab, sidebar selection, current document section, scroll target. Two windows hold independent values.
3. Both are size-limited key-value stores. A custom type needs RawRepresentable/Codable; large Data/arrays/images belong in SwiftData or a file, never in scene/app storage.

The wrapper test: would two open windows legitimately disagree about this value? Yes → per-window UI state → @SceneStorage. No, it's one app-wide truth → @AppStorage. Full reasoning + the ❌→✅ rewrites: references/wrapper-choice.md.

Grounded ✅ (real call site, not a placeholder). Per-window UI state restores per scene when its key is bound to @SceneStorage. The canonical shape — consensus from swiftui-ctx lookup SceneStorage (introduced_macos 11.0; top shapes ("selectedTab"), ("viewMode"), ("selectedSettingsSection"), each ~13%) — and a verified shipping example:

// ✅ TableProApp/TablePro — @SceneStorage restores per-window search text on relaunch
@SceneStorage("tableList.searchText") private var searchText = ""

• Example (swiftui-ctx file ex_596e50becb --smart, real GitHub permalink): https://github.com/TableProApp/TablePro/blob/e3afc6457cd819eca5226c3874a9b4d7ad318a67/TableProMobile/TableProMobile/Views/TableListView.swift#L12
• Spec (doc:, via Sosumi): https://sosumi.ai/documentation/swiftui/scenestorage (macOS 11.0+, accessed 2026-06-07).

Re-fetch the live consensus + permalink in step VERIFY/FIX rather than trusting this snapshot.

Defect index (sr-01 … sr-11)

id · tell · severity · fix · open reference. Severities: hard-fail (build break / never-correct), warning (compiles but wrong/amnesiac), advisory (judgment / perf). All fixes are flag-only: every correction here turns on developer intent (is this value app-wide or per-window?), so none auto-applies.

id	One-line tell	Sev	Fix	Reference
sr-01	.restorationIdentifier( / @StateRestoration / UIStateRestoring / restorationClass (UIKit/invented on SwiftUI Mac)	hard-fail	flag	restoration-gating.md
sr-02	@SceneStorage holding an app-wide preference (one truth for all windows)	warning	flag	wrapper-choice.md
sr-03	@AppStorage holding per-window UI state (tab/sidebar/detail/scroll selection) → leaks across windows	warning	flag	wrapper-choice.md
sr-04	hand-rolled UserDefaults.standard.set/object(forKey:) for a simple pref @AppStorage fits	warning	flag	wrapper-choice.md
sr-05	TabView/NavigationSplitView/List selection bound to plain @State (no @SceneStorage) → relaunch amnesia	warning	flag	navigation-restoration.md
sr-06	NavigationPath never persisted — no NavigationPath(codable:) / .codable round-trip into @SceneStorage	advisory	flag	navigation-restoration.md
sr-07	custom type in @AppStorage/@SceneStorage without RawRepresentable/Codable conformance	warning	flag	wrapper-choice.md
sr-08	oversized Data/array/image stored in @SceneStorage/@AppStorage (size-limited) → SwiftData/file	warning	flag	wrapper-choice.md
sr-09	declared CFBundleURLSchemes / custom URL scheme but no onOpenURL/onContinueUserActivity handler (dead deep link)	warning	flag	deep-linking.md
sr-10	restorationBehavior(_:) used/ungated under a deployment target < macOS 15	warning	flag	restoration-gating.md
sr-11	focusedSceneValue(_:_:) — key-path form macOS 12 / object form macOS 14; verify floor + gate	advisory	flag	restoration-gating.md

One claim is FLOOR-SENSITIVE — never assert without VERIFY: focusedSceneValue has two floors (the key-path overload is macOS 12, the object overload macOS 14, per the brief); confirm which overload the code uses before quoting a floor (source: verify against Xcode 26 SDK until confirmed via swiftui-ctx + Sosumi). restorationBehavior is macOS 15.

The real API, at a glance

Real (and their macOS floors — confirmed via swiftui-ctx introduced_macos + Sosumi): @AppStorage (macOS 11), @SceneStorage (macOS 11), NavigationPath + NavigationPath(codable:) / .codable (macOS 13), onOpenURL(perform:) (macOS 11), onContinueUserActivity(_:perform:) (macOS 11), handlesExternalEvents(matching:) (macOS 11 — Mac, iOS, visionOS; no tvOS/watchOS), restorationBehavior(_:) (macOS 15), focusedSceneValue(_:_:) (key-path macOS 12 / object macOS 14). Floor values live in <swiftui-plugin-root>/references/_shared/floors-master.md — read, never restate.

Hallucinated / wrong-framework (never on SwiftUI macOS): .restorationIdentifier(...), @StateRestoration, UIStateRestoring, restorationClass, encodeRestorableState/decodeRestorableState (all UIKit UIViewController/NSResponder restoration, not SwiftUI). @FocusedDocument is not a real symbol — use a custom FocusedValues key (<swiftui-plugin-root>/references/_shared/hallucination-blacklist.md). The full ❌→✅ rewrites: references/wrapper-choice.md + references/restoration-gating.md.

The 8-step audit workflow (execute verbatim)

1. ORIENT. tree / find the SwiftUI sources. Read the deployment target (project.pbxproj MACOSX_DEPLOYMENT_TARGET, or Package.swift platforms:). It is load-bearing: sr-10 fires only when the floor is below macOS 15, sr-11 only below the relevant focusedSceneValue floor. Also read Info.plist/project.pbxproj for any declared CFBundleURLSchemes (needed for sr-09). Record the target and any declared scheme.
2. LOCATE. Run the shared hybrid lint runner: bash <swiftui-plugin-root>/scripts/swiftui-lint.sh --skill audit-swiftui-state-restoration --dir <sources> --json /tmp/sr.json --sarif /tmp/sr.sarif. It runs this skill's tier-1 grep tells (lint/grep-tells.tsv) + the tier-2 structural ast-grep rule (lint/ast-grep/*.yml — the restorationBehavior-not-inside-a-#available(macOS 15)-gate rule grep can't express), plus a per-file parse probe, and emits unified JSON + SARIF. Read its parse_warnings — a flagged file did not fully parse, so a structural miss can't masquerade as clean; READ those by hand. The runner only LOCATES. Engine + rule-file format + degradation: <swiftui-plugin-root>/references/_shared/lint-architecture.md.
3. READ. Open every located file in full — never pattern-match-and-patch blind. The wrapper-choice defects (sr-02/03) are invisible to grep: only reading the value's meaning (app-wide vs per-window), its scope, and how many windows the app opens reveals the defect. Build a per-file inventory: each stored property + wrapper + value semantics + the wrapper test verdict.
4. DETECT. Apply the index. Assign each candidate a confidence; report a finding only at 100% certainty (e.g. a UIKit restoration symbol on SwiftUI, a custom type with no RawRepresentable, a restorationBehavior under a <15 floor).
5. VERIFY. For anything ≤ ~70% confidence (a floor you can't place — especially focusedSceneValue's two overloads — a symbol you're unsure exists, a "does this persist" behavior claim), run both evidence sources. (a) Practice — bash <swiftui-plugin-root>/scripts/swiftui-ctx lookup <api> --json (and swiftui-ctx deprecated <api> for a currency rule): read its consensus (the canonical shape), deprecated+replacement, recommended permalink, introduced_macos, and co_occurs_with; a lookup exit 3 (not-found, with a did-you-mean suggestion) corroborates a hallucination — no shipping Mac app uses the symbol. (b) Spec — confirm via Sosumi: curl -sSL https://sosumi.ai/<apple-path> using references/source-directory.md for the path and <swiftui-plugin-root>/references/_shared/sosumi-reference.md for the protocol (never WebFetch developer.apple.com; this domain's parenthesized-symbol JSON 404s — Sosumi only). Cross-check introduced_macos against floors-master.md. The CLI contract is <swiftui-plugin-root>/references/_shared/swiftui-ctx-reference.md. Promote with the citation or discard.
6. REPORT. Write each confirmed finding (output contract below). One finding per file, zero-padded, ordered. Write the run's _index.md.
7. FIX. All findings here are fix_mode: flag-only — leave each open with the ✅ in ## Correct. The ✅ is not a hand-written snippet: it is the swiftui-ctx consensus shape put in ## Correct, backed by a real macOS example fetched with bash <swiftui-plugin-root>/scripts/swiftui-ctx file <recommended.id> --smart whose GitHub permalink (plus the Sosumi doc:) goes in ## Source as the canonical example. The fix-safety protocol (<swiftui-plugin-root>/references/_shared/fix-safety-protocol.md) still governs: clean-tree gate, findings-first, never weaken a check. Because the wrapper swap turns on intent, never auto-apply it.
8. DOUBLE-CHECK. Re-read each flagged property to confirm the ✅ wrapper matches the value's semantics (the wrapper test still holds). Re-confirm every citation still resolves and still says the floor you quoted. If a suggested ✅ introduces a new tell (e.g. moving a blob to @SceneStorage now needs Codable), loop that file back to DETECT.

Confidence gating (load-bearing)

Report a finding only at 100% certainty. The wrapper-confusion defects (sr-02/03/04) are semantic — treat them as ≤70% until READ confirms the value's app-wide-vs-per-window meaning; route them through VERIFY for the floor and through the wrapper test for the verdict. Never emit a speculative finding. Nothing here auto-fixes — every finding is fix_mode: flag-only.

Output contract

Inherits the toolkit's unified contract (full schema + body sections + frontmatter keys: <swiftui-plugin-root>/references/_shared/finding-schema.md — do not restate it). Specialized for this domain:

• Findings: swiftui-audits/state-restoration/<context>/NN-slug.md (one finding per file, zero-padded, ordered). Per-run index: swiftui-audits/state-restoration/_index.md.
• domain: state-restoration. fix_mode is flag-only for every defect. An optional descriptive additive field storage_kind (app | scene | userdefaults | navigation | url) may record which store the finding concerns; emit cross_ref on shared-seam findings (sr-08 → audit-swiftui-swiftdata; sr-05/06 → audit-swiftui-navigation-toolbars; sr-10 → audit-swiftui-scenes-windows; sr-11 → audit-swiftui-menus-commands). availability reads from floors-master.md. source is an Apple URL + access date (fetched via Sosumi) or verify against Xcode 26 SDK.

Starter <context> folders (file here when…):

<context>	File a finding here when…
hallucinated-api/	a UIKit/invented restoration symbol appears on SwiftUI (sr-01)
wrapper-confusion/	the wrong wrapper holds the value — scene/app swapped, or hand-rolled UserDefaults (sr-02, sr-03, sr-04)
relaunch-amnesia/	selection or navigation is not restored — plain @State selection, unpersisted NavigationPath (sr-05, sr-06)
storage-correctness/	a non-conforming custom type or an oversized blob sits in key-value storage (sr-07, sr-08)
deep-linking/	a declared URL scheme/activity has no handler (sr-09)
restoration-gating/	restorationBehavior/focusedSceneValue is ungated under its floor (sr-10, sr-11)

New-folder rule: if a finding does not fit any existing context folder, create a new one under swiftui-audits/state-restoration/ with a lowercase-hyphen slug naming the sub-category, and note it in the run's _index.md. Prefer an existing folder when the fit is reasonable; consistency across runs is a hard requirement. Two runs over the same code produce structurally identical trees.

Reference routing

File	Open when
references/wrapper-choice.md	the @AppStorage↔@SceneStorage↔UserDefaults decision, the wrapper test, custom-type conformance, oversized-blob offload (sr-02/03/04/07/08)
references/navigation-restoration.md	restoring selection + NavigationPath across relaunch — @SceneStorage selection, NavigationPath(codable:) round-trip (sr-05/06)
references/deep-linking.md	URL scheme + onOpenURL/onContinueUserActivity/handlesExternalEvents wiring (sr-09)
references/restoration-gating.md	the hallucinated/UIKit symbols, restorationBehavior (macOS 15) + focusedSceneValue two-floor gating (sr-01/10/11)
references/source-directory.md	step VERIFY — the Apple/WWDC/practitioner source map fetched via Sosumi
lint/grep-tells.tsv + lint/ast-grep/*.yml	step LOCATE — this skill's declarative lint rule set fed to the shared runner (tier-1 grep tells + the one tier-2 structural rule); edit here to tune detection

Shared toolkit references (point in, never restate):

Shared file	For
<swiftui-plugin-root>/references/_shared/floors-master.md	every floor/availability value (the reconciled truth)
<swiftui-plugin-root>/references/_shared/hallucination-blacklist.md	the canonical invented-name list (incl. @FocusedDocument)
<swiftui-plugin-root>/references/_shared/macos-arm-gating.md	the macOS-arm gating rule + wrong-arm failure (sr-10/11)
<swiftui-plugin-root>/references/_shared/finding-schema.md	the unified finding schema + frontmatter keys
<swiftui-plugin-root>/references/_shared/fix-safety-protocol.md	the fix-safety protocol (step 7)
<swiftui-plugin-root>/references/_shared/sosumi-reference.md	the Apple-doc spec fetch protocol (step 5 VERIFY)
<swiftui-plugin-root>/references/_shared/swiftui-ctx-reference.md	the practice-corpus CLI contract — lookup/deprecated/file --smart for the consensus shape + permalinked example (steps 5 VERIFY · 7 FIX)
<swiftui-plugin-root>/references/_shared/cross-ref-graph.md	seam ownership + cross_ref targets

Detection accelerator

bash <swiftui-plugin-root>/scripts/swiftui-lint.sh --skill audit-swiftui-state-restoration --dir <files-or-dir> [--json out.json] [--sarif out.sarif] — the toolkit's one shared hybrid lint engine, fed this skill's declarative rules: tier-1 grep tells (lint/grep-tells.tsv, sr-01/02/03/04/05/06/07/08/09/10/11) + tier-2 ast-grep (lint/ast-grep/sr-10-restorationbehavior-ungated.yml — restorationBehavior NOT inside an #available(macOS 15, *) gate, a gate-scope rule grep cannot express). It runs a per-file parse probe (surfaces "did not fully parse" so a structural miss can't look clean), emits unified JSON + SARIF, exits 2 on any hard-fail (sr-01) for a CI gate, and degrades to grep-only with a notice if ast-grep is unreachable (npx --package @ast-grep/cli ast-grep; faster: brew install ast-grep). It only LOCATES — always READ each hit in full before reporting (step 3). The thin scripts/sr-lint.sh is a pointer to this runner. Engine + rule-file format + JSON/SARIF shape + safety rails: <swiftui-plugin-root>/references/_shared/lint-architecture.md.