feat: get static feature flags in JS

apps/common-app/src/apps/reanimated/examples/RuntimeTests/RuntimeTestsExample.tsx

@@ -141,6 +141,7 @@ export default function RuntimeTestsExample() {
           importTest: () => {
             require('./tests/advancedAPI/useFrameCallback.test');
             require('./tests/advancedAPI/measure.test');
+            require('./tests/advancedAPI/staticFeatureFlags.test');
           },
         },
         {

apps/common-app/src/apps/reanimated/examples/RuntimeTests/tests/advancedAPI/staticFeatureFlags.test.tsx

@@ -0,0 +1,19 @@
+import { getStaticFeatureFlag as getStaticFeatureFlagReanimated } from 'react-native-reanimated';
+import { getStaticFeatureFlag as getStaticFeatureFlagWorklets } from 'react-native-worklets';
+
+import { describe, expect, test } from '../../ReJest/RuntimeTestsApi';
+
+/**
+ * This flag is `false` by default - this test checks if setting it
+ * to `true` in `package.json` is picked up on the native side.
+ */
+const RUNTIME_TEST_FLAG = 'RUNTIME_TEST_FLAG';
+
+describe('Test getting static feature flags', () => {
+  test('from Reanimated', () => {
+    expect(getStaticFeatureFlagReanimated(RUNTIME_TEST_FLAG)).toBe(true);
+  });
+  test('from Worklets', () => {
+    expect(getStaticFeatureFlagWorklets(RUNTIME_TEST_FLAG)).toBe(true);
+  });
+});

apps/common-app/src/apps/reanimated/examples/RuntimeTests/tests/advancedAPI/useFrameCallback.test.tsx

@@ -64,7 +64,7 @@ describe('Test *****useFrameCallback*****', () => {
         await render(<InvalidFrameCallback />);
         await wait(200);
       }).toThrow(
-        'Error: [Worklets] Tried to synchronously call a non-worklet function `imNotAWorklet` on the UI thread.\nSee https://docs.swmansion.com/react-native-reanimated/docs/guides/troubleshooting#tried-to-synchronously-call-a-non-worklet-function-on-the-ui-thread for more details., js engine: Worklets',
+        'Error: [Worklets] Tried to synchronously call a non-worklet function `imNotAWorklet` on the UI thread.\nSee https://docs.swmansion.com/react-native-reanimated/docs/guides/troubleshooting#tried-to-synchronously-call-a-non-worklet-function-on-the-ui-thread for more details.',
       );
     });
   });

apps/fabric-example/ios/Podfile.lock

@@ -3078,10 +3078,10 @@ SPEC CHECKSUMS:
   RNCClipboard: 4b58c780f63676367640f23c8e114e9bd0cf86ac
   RNCMaskedView: 5ef8c95cbab95334a32763b72896a7b7d07e6299
   RNGestureHandler: 3a73f098d74712952870e948b3d9cf7b6cae9961
-  RNReanimated: bedbdc2587402b124d504cd243b6eed208dc1a5c
+  RNReanimated: e8938e49be3ffc8f3712521871f9f883c0ecc293
   RNScreens: 6ced6ae8a526512a6eef6e28c2286e1fc2d378c3
   RNSVG: 6f39605a4c4d200b11435c35bd077553c6b5963a
-  RNWorklets: f928b6ff86463bbdcfbc62043a6cf411d6cf9e70
+  RNWorklets: 2c4d82749bbe199a1e6d9fcd696955bd905545b5
   SocketRocket: d4aabe649be1e368d1318fdf28a022d714d65748
   Yoga: 00013dd9cde63a2d98e8002fcc4f5ddb66c10782
 

apps/fabric-example/package.json

@@ -21,5 +21,15 @@
   },
   "installConfig": {
     "selfReferences": false
+  },
+  "reanimated": {
+    "staticFeatureFlags": {
+      "RUNTIME_TEST_FLAG": true
+    }
+  },
+  "worklets": {
+    "staticFeatureFlags": {
+      "RUNTIME_TEST_FLAG": true
+    }
   }
 }

apps/macos-example/package.json

@@ -31,5 +31,15 @@
   "installConfig": {
     "hoistingLimits": "workspaces",
     "selfReferences": false
+  },
+  "reanimated": {
+    "staticFeatureFlags": {
+      "RUNTIME_TEST_FLAG": true
+    }
+  },
+  "worklets": {
+    "staticFeatureFlags": {
+      "RUNTIME_TEST_FLAG": true
+    }
   }
 }

apps/tvos-example/ios/Podfile.lock

@@ -2104,8 +2104,8 @@ SPEC CHECKSUMS:
   ReactAppDependencyProvider: 29fb2827ec6c6c8ee9ee9108e838b4e0e4e1b730
   ReactCodegen: 3a01f76123e04b8b945d43e5ffccae6f90f4a26e
   ReactCommon: 59e7bd3cf331ba77a96a75e6b603abf05883b102
-  RNReanimated: 4e7fb9acca641e2bed32e300c9dddbd350f5210d
-  RNWorklets: 9d4d5a0ef70d5e6385cbd28bfa4e91dd6e18c97e
+  RNReanimated: 72d815b95ba0f8703c4b47acc58877c7c35ee0dd
+  RNWorklets: 7f0681f2328f76943ca7f185d71a698eaceb6ce8
   SocketRocket: d4aabe649be1e368d1318fdf28a022d714d65748
   Yoga: 770a077e3a222f162c2e0c8a95e7e997b7682a8e
 

apps/tvos-example/package.json

@@ -40,5 +40,15 @@
   "installConfig": {
     "hoistingLimits": "workspaces",
     "selfReferences": false
+  },
+  "reanimated": {
+    "staticFeatureFlags": {
+      "RUNTIME_TEST_FLAG": true
+    }
+  },
+  "worklets": {
+    "staticFeatureFlags": {
+      "RUNTIME_TEST_FLAG": true
+    }
   }
 }

packages/react-native-reanimated/Common/cpp/reanimated/NativeModules/ReanimatedModuleProxy.cpp

@@ -308,11 +308,18 @@ jsi::Value ReanimatedModuleProxy::getViewProp(
   return jsi::Value::undefined();
 }
 
+jsi::Value ReanimatedModuleProxy::getStaticFeatureFlag(
+    jsi::Runtime &rt,
+    const jsi::Value &name) {
+  return reanimated::StaticFeatureFlags::getFlag(name.asString(rt).utf8(rt));
+}
+
 jsi::Value ReanimatedModuleProxy::setDynamicFeatureFlag(
     jsi::Runtime &rt,
     const jsi::Value &name,
     const jsi::Value &value) {
-  DynamicFeatureFlags::setFlag(name.asString(rt).utf8(rt), value.asBool());
+  reanimated::DynamicFeatureFlags::setFlag(
+      name.asString(rt).utf8(rt), value.asBool());
   return jsi::Value::undefined();
 }
 

packages/react-native-reanimated/Common/cpp/reanimated/NativeModules/ReanimatedModuleProxy.h

@@ -80,10 +80,13 @@ class ReanimatedModuleProxy
       const jsi::Value &propName,
       const jsi::Value &callback) override;
 
+  jsi::Value getStaticFeatureFlag(jsi::Runtime &rt, const jsi::Value &name)
+      override;
   jsi::Value setDynamicFeatureFlag(
       jsi::Runtime &rt,
       const jsi::Value &name,
       const jsi::Value &value) override;
+
   jsi::Value configureLayoutAnimationBatch(
       jsi::Runtime &rt,
       const jsi::Value &layoutAnimationsBatch) override;

packages/react-native-reanimated/Common/cpp/reanimated/NativeModules/ReanimatedModuleProxySpec.cpp

@@ -62,6 +62,15 @@ static jsi::Value REANIMATED_SPEC_PREFIX(unregisterSensor)(
   return jsi::Value::undefined();
 }
 
+static jsi::Value REANIMATED_SPEC_PREFIX(getStaticFeatureFlag)(
+    jsi::Runtime &rt,
+    TurboModule &turboModule,
+    const jsi::Value *args,
+    size_t) {
+  return static_cast<ReanimatedModuleProxySpec *>(&turboModule)
+      ->getStaticFeatureFlag(rt, std::move(args[0]));
+}
+
 static jsi::Value REANIMATED_SPEC_PREFIX(setDynamicFeatureFlag)(
     jsi::Runtime &rt,
     TurboModule &turboModule,
@@ -224,6 +233,8 @@ ReanimatedModuleProxySpec::ReanimatedModuleProxySpec(
       MethodMetadata{3, REANIMATED_SPEC_PREFIX(getViewProp)};
   methodMap_["registerSensor"] =
       MethodMetadata{4, REANIMATED_SPEC_PREFIX(registerSensor)};
+  methodMap_["getStaticFeatureFlag"] =
+      MethodMetadata{1, REANIMATED_SPEC_PREFIX(getStaticFeatureFlag)};
   methodMap_["unregisterSensor"] =
       MethodMetadata{1, REANIMATED_SPEC_PREFIX(unregisterSensor)};
   methodMap_["setDynamicFeatureFlag"] =

packages/react-native-reanimated/Common/cpp/reanimated/NativeModules/ReanimatedModuleProxySpec.h

@@ -56,7 +56,11 @@ class JSI_EXPORT ReanimatedModuleProxySpec : public TurboModule {
       jsi::Runtime &rt,
       const jsi::Value &listenerId) = 0;
 
-  // other
+  // feature flags
+  virtual jsi::Value getStaticFeatureFlag(
+      jsi::Runtime &rt,
+      const jsi::Value &name) = 0;
+
   virtual jsi::Value setDynamicFeatureFlag(
       jsi::Runtime &rt,
       const jsi::Value &name,

packages/react-native-reanimated/Common/cpp/reanimated/Tools/FeatureFlags.h

@@ -14,7 +14,7 @@ class StaticFeatureFlags {
 // itself instead of the flag value
 #define TOSTRING(x) XTOSTRING(x)
 
-  static consteval bool getFlag(const std::string_view &name) {
+  static constexpr bool getFlag(const std::string_view &name) {
     std::string nameStr = name.data();
     std::string featureFlags = TOSTRING(REANIMATED_FEATURE_FLAGS);
     if (featureFlags.find("[" + nameStr + ":") == std::string::npos) {
@@ -25,7 +25,7 @@ class StaticFeatureFlags {
 
 #else
 
-  static consteval bool getFlag(const std::string_view &) {
+  static constexpr bool getFlag(const std::string_view &) {
     return false;
   }
 

packages/react-native-reanimated/__typetests__/common/FeatureFlagTest.tsx

@@ -0,0 +1,10 @@
+/* eslint-disable @typescript-eslint/no-unused-vars */
+import { getStaticFeatureFlag } from '../..';
+
+function GetStaticFeatureFlagTest() {
+  // ok - this flag exists
+  getStaticFeatureFlag('RUNTIME_TEST_FLAG');
+
+  // @ts-expect-error - this flag does not exist
+  getStaticFeatureFlag('NON_EXISTENT_FLAG');
+}

packages/react-native-reanimated/src/ReanimatedModule/NativeReanimated.ts

@@ -161,6 +161,10 @@ See https://docs.swmansion.com/react-native-reanimated/docs/guides/troubleshooti
     );
   }
 
+  getStaticFeatureFlag(name: string): boolean {
+    return this.#reanimatedModuleProxy.getStaticFeatureFlag(name);
+  }
+
   setDynamicFeatureFlag(name: string, value: boolean) {
     this.#reanimatedModuleProxy.setDynamicFeatureFlag(name, value);
   }
@@ -248,6 +252,9 @@ See https://docs.swmansion.com/react-native-reanimated/docs/guides/troubleshooti
 class DummyReanimatedModuleProxy implements ReanimatedModuleProxy {
   configureLayoutAnimationBatch(): void {}
   setShouldAnimateExitingForTag(): void {}
+  getStaticFeatureFlag(): boolean {
+    return false;
+  }
   setDynamicFeatureFlag(): void {}
   subscribeForKeyboardEvents(): number {
     return -1;

packages/react-native-reanimated/src/ReanimatedModule/js-reanimated/JSReanimated.ts

@@ -261,7 +261,12 @@ class JSReanimated implements IReanimatedModule {
     throw new ReanimatedError('getViewProp is not available in JSReanimated.');
   }
 
-  setDynamicFeatureFlag(_name: string, _value: boolean): void {
+  getStaticFeatureFlag(): boolean {
+    // mock implementation
+    return false;
+  }
+
+  setDynamicFeatureFlag(): void {
     // noop
   }
 

packages/react-native-reanimated/src/ReanimatedModule/reanimatedModuleProxy.ts

@@ -41,6 +41,8 @@ export interface ReanimatedModuleProxy {
 
   unregisterSensor(sensorId: number): void;
 
+  getStaticFeatureFlag(name: string): boolean;
+
   setDynamicFeatureFlag(name: string, value: boolean): void;
 
   subscribeForKeyboardEvents(

packages/react-native-reanimated/src/featureFlags/dynamicFlags.ts → packages/react-native-reanimated/src/featureFlags/index.ts

@@ -1,6 +1,7 @@
 'use strict';
 import { logger } from '../common';
 import { ReanimatedModule } from '../ReanimatedModule';
+import type StaticFeatureFlagsJSON from './staticFlags.json';
 
 type DynamicFlagsType = {
   EXPERIMENTAL_MUTABLE_OPTIMIZATION: boolean;
@@ -9,7 +10,6 @@ type DynamicFlagsType = {
 };
 type DynamicFlagName = keyof Omit<Omit<DynamicFlagsType, 'setFlag'>, 'init'>;
 
-/** @knipIgnore */
 export const DynamicFlags: DynamicFlagsType = {
   EXPERIMENTAL_MUTABLE_OPTIMIZATION: false,
 
@@ -43,3 +43,33 @@ export function setDynamicFeatureFlag(
 ): void {
   DynamicFlags.setFlag(name, value);
 }
+
+/**
+ * This constant is needed for typechecking and preserving static typechecks in
+ * generated .d.ts files. Without it, the static flags resolve to an object
+ * without specific keys.
+ */
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const DefaultStaticFeatureFlags = {
+  DISABLE_COMMIT_PAUSING_MECHANISM: false,
+  ANDROID_SYNCHRONOUSLY_UPDATE_UI_PROPS: false,
+  UNSTABLE_CSS_ANIMATIONS_FOR_SVG_COMPONENTS: false,
+  RUNTIME_TEST_FLAG: false,
+} as const satisfies typeof StaticFeatureFlagsJSON;
+
+type StaticFeatureFlagsSchema = {
+  -readonly [K in keyof typeof DefaultStaticFeatureFlags]: boolean;
+};
+
+const staticFeatureFlags: Partial<StaticFeatureFlagsSchema> = {};
+
+export function getStaticFeatureFlag(
+  name: keyof StaticFeatureFlagsSchema
+): boolean {
+  if (name in staticFeatureFlags) {
+    return staticFeatureFlags[name]!;
+  }
+  const featureFlagValue = ReanimatedModule.getStaticFeatureFlag(name);
+  staticFeatureFlags[name] = featureFlagValue;
+  return featureFlagValue;
+}

packages/react-native-reanimated/src/featureFlags/staticFlags.json

@@ -1,5 +1,6 @@
 {
   "DISABLE_COMMIT_PAUSING_MECHANISM": false,
   "ANDROID_SYNCHRONOUSLY_UPDATE_UI_PROPS": false,
-  "UNSTABLE_CSS_ANIMATIONS_FOR_SVG_COMPONENTS": false
+  "UNSTABLE_CSS_ANIMATIONS_FOR_SVG_COMPONENTS": false,
+  "RUNTIME_TEST_FLAG": false
 }

packages/react-native-reanimated/src/index.ts

@@ -102,7 +102,7 @@ export {
 export * from './css';
 export type { EasingFunctionFactory } from './Easing';
 export { Easing } from './Easing';
-export { setDynamicFeatureFlag } from './featureFlags/dynamicFlags';
+export { getStaticFeatureFlag, setDynamicFeatureFlag } from './featureFlags';
 export type { FrameInfo } from './frameCallback';
 export type { AnimatedProps, EntryOrExitLayoutType } from './helperTypes';
 export type {

packages/react-native-reanimated/src/mutables.ts

@@ -10,7 +10,7 @@ import {
 
 import { IS_JEST, logger, ReanimatedError, SHOULD_BE_USE_WEB } from './common';
 import type { Mutable } from './commonTypes';
-import { DynamicFlags } from './featureFlags/dynamicFlags';
+import { DynamicFlags } from './featureFlags';
 import { isFirstReactRender, isReactRendering } from './reactUtils';
 import { valueSetter } from './valueSetter';
 

packages/react-native-worklets/Common/cpp/worklets/NativeModules/JSIWorkletsModuleProxy.cpp

@@ -207,6 +207,9 @@ std::vector<jsi::PropNameID> JSIWorkletsModuleProxy::getPropertyNames(
       jsi::PropNameID::forAscii(rt, "scheduleOnRuntime"));
   propertyNames.emplace_back(
       jsi::PropNameID::forAscii(rt, "reportFatalErrorOnJS"));
+
+  propertyNames.emplace_back(
+      jsi::PropNameID::forAscii(rt, "getStaticFeatureFlag"));
   propertyNames.emplace_back(
       jsi::PropNameID::forAscii(rt, "setDynamicFeatureFlag"));
 
@@ -669,6 +672,20 @@ jsi::Value JSIWorkletsModuleProxy::get(
   }
 #endif // WORKLETS_BUNDLE_MODE
 
+  if (name == "getStaticFeatureFlag") {
+    return jsi::Function::createFromHostFunction(
+        rt,
+        propName,
+        2,
+        [](jsi::Runtime &rt,
+           const jsi::Value &thisValue,
+           const jsi::Value *args,
+           size_t count) {
+          return worklets::StaticFeatureFlags::getFlag(
+              /* name */ args[0].asString(rt).utf8(rt));
+        });
+  }
+
   if (name == "setDynamicFeatureFlag") {
     return jsi::Function::createFromHostFunction(
         rt,
@@ -678,7 +695,7 @@ jsi::Value JSIWorkletsModuleProxy::get(
            const jsi::Value &thisValue,
            const jsi::Value *args,
            size_t count) {
-          DynamicFeatureFlags::setFlag(
+          worklets::DynamicFeatureFlags::setFlag(
               /* name */ args[0].asString(rt).utf8(rt),
               /* value */ args[1].asBool());
           return jsi::Value::undefined();

packages/react-native-worklets/Common/cpp/worklets/Tools/FeatureFlags.h

@@ -14,7 +14,7 @@ class StaticFeatureFlags {
 // itself instead of the flag value
 #define TOSTRING(x) XTOSTRING(x)
 
-  static consteval bool getFlag(const std::string_view &name) {
+  static constexpr bool getFlag(const std::string_view &name) {
     std::string nameStr = name.data();
     std::string featureFlags = TOSTRING(WORKLETS_FEATURE_FLAGS);
     if (featureFlags.find("[" + nameStr + ":") == std::string::npos) {
@@ -25,7 +25,7 @@ class StaticFeatureFlags {
 
 #else
 
-  static consteval bool getFlag(const std::string_view &) {
+  static constexpr bool getFlag(const std::string_view &) {
     return false;
   }
 

packages/react-native-worklets/__typetests__/FeatureFlagTest.tsx

@@ -0,0 +1,10 @@
+/* eslint-disable @typescript-eslint/no-unused-vars */
+import { getStaticFeatureFlag } from '..';
+
+function GetStaticFeatureFlagTest() {
+  // ok - this flag exists
+  getStaticFeatureFlag('RUNTIME_TEST_FLAG');
+
+  // @ts-expect-error - this flag does not exist
+  getStaticFeatureFlag('NON_EXISTENT_FLAG');
+}