fix: cache metadata UIAppearance setters

Author: DjDeveloperr

HANDOFF.md

@@ -111,6 +111,31 @@ During this thread `agent-device` was version `0.18.0`; the npm package is
 
 ## Current Verified State
 
+Update from 2026-06-29 09:00 EDT:
+
+- Simulator-only rule remains active. Do not use physical iPhone/iPad devices.
+- GitHub Actions run `28372181901` on `45c6df65` kept builds and macOS tests
+  green, but still failed iOS only in `ApiTests.js Appearance`:
+  `UILabel.appearance().textColor` read back `undefined`.
+- Narrow follow-up runtime fix in progress:
+  - The remaining gap was the metadata-backed native property setter path on
+    UIAppearance proxy objects. It returned before the class-scoped
+    UIAppearance value cache used by the runtime-discovered setter path.
+  - Metadata-backed property setters now write the same UIAppearance
+    class-scoped expando after a successful native setter call, so future
+    reads can return the set value even when the native proxy getter is not
+    readable.
+- Local verification after this patch:
+  - Runtime RN JS tests passed:
+    `for f in packages/react-native/test/*.test.js; do node "$f" || exit 1; done`.
+  - `npm run check:ffi-boundaries` passed.
+  - `git diff --check` passed.
+  - `npm run build:macos-cli` passed.
+- Not done:
+  - Commit/push this metadata-backed UIAppearance setter-cache fix and watch
+    fresh PR CI.
+  - If CI turns green, resume the dedicated simulator-only RNS parity sweep.
+
 Update from 2026-06-29 08:28 EDT:
 
 - Simulator-only rule remains active. Do not use physical iPhone/iPad devices.

NativeScript/ffi/shared/bridge/HostObjects.mm

@@ -1778,6 +1778,12 @@ throw JSError(
         Value args[] = {Value(runtime, value)};
         callObjCSelector(runtime, bridge_, object_, false,
                          setterMember.selectorName, &setterMember, args, 1);
+        if (Class appearanceClass =
+                taggedAppearanceProxyClass(runtime, bridge_, object_)) {
+          bridge_->setObjectExpando(
+              runtime, appearanceClass,
+              appearanceProxyExpandoPropertyKey(property), value);
+        }
         NATIVE_API_SET_RETURN(true);
       }
     }

PROGRESS.md

@@ -17,6 +17,33 @@ TypeScript/UI worklets.
 
 ## Latest Update - 2026-06-29
 
+### 2026-06-29 09:00 EDT - cached metadata-backed UIAppearance setters
+
+- Goal:
+  - Keep PR #46 on the generic runtime primitive path and unblock the final
+    simulator-only RN Screens parity sweep; no physical devices were used.
+- CI finding:
+  - GitHub Actions run `28372181901` on `45c6df65` kept builds and macOS tests
+    green, but still failed iOS `ApiTests.js Appearance` only:
+    `UILabel.appearance().textColor` read back as `undefined`.
+  - That means static `appearance*` result tagging was not enough by itself:
+    the proxy was tagged, but the setter path still skipped the cache.
+- Changes:
+  - Metadata-backed native property setters on UIAppearance proxy objects now
+    populate the same target-class-scoped appearance expando cache as
+    runtime-discovered setters.
+  - This keeps the fix generic to UIKit UIAppearance proxies and avoids
+    broad get-time Objective-C probing.
+- Verification:
+  - Runtime RN JS tests passed:
+    `for f in packages/react-native/test/*.test.js; do node "$f" || exit 1; done`.
+  - `npm run check:ffi-boundaries` passed.
+  - `git diff --check` passed.
+  - `npm run build:macos-cli` passed.
+- Still next:
+  - Commit/push the setter-cache fix, watch fresh PR CI, then return to the
+    dedicated simulator-only RNS parity sweep if CI is green.
+
 ### 2026-06-29 08:28 EDT - patched static UIAppearance selector result tagging
 
 - Goal: