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node_modules/react-native/Libraries/Components/LayoutConformance/LayoutConformance.d.ts

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+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import type * as React from 'react';
+
+type LayoutConformanceProps = {
+  /**
+   * strict: Layout in accordance with W3C spec, even when breaking
+   * compatibility: Layout with the same behavior as previous versions of React Native
+   */
+  mode: 'strict' | 'compatibility';
+  children: React.ReactNode;
+};
+
+export const experimental_LayoutConformance: React.ComponentType<LayoutConformanceProps>;

node_modules/react-native/Libraries/Components/LayoutConformance/LayoutConformance.js

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+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ */
+
+import StyleSheet from '../../StyleSheet/StyleSheet';
+import LayoutConformanceNativeComponent from './LayoutConformanceNativeComponent';
+import * as React from 'react';
+
+export type LayoutConformanceProps = $ReadOnly<{
+  /**
+   * strict: Layout in accordance with W3C spec, even when breaking
+   * compatibility: Layout with the same behavior as previous versions of React Native
+   */
+  mode: 'strict' | 'compatibility',
+
+  children: React.Node,
+}>;
+
+// We want a graceful fallback for apps using legacy arch, but need to know
+// ahead of time whether the component is available, so we test for global.
+// This does not correctly handle mixed arch apps (which is okay, since we just
+// degrade the error experience).
+const isFabricUIManagerInstalled = global?.nativeFabricUIManager != null;
+
+function LayoutConformance(props: LayoutConformanceProps): React.Node {
+  return (
+    <LayoutConformanceNativeComponent {...props} style={styles.container} />
+  );
+}
+
+function UnimplementedLayoutConformance(
+  props: LayoutConformanceProps,
+): React.Node {
+  if (__DEV__) {
+    const warnOnce = require('../../Utilities/warnOnce').default;
+
+    warnOnce(
+      'layoutconformance-unsupported',
+      '"LayoutConformance" is only supported in the New Architecture',
+    );
+  }
+
+  return props.children;
+}
+
+export default (isFabricUIManagerInstalled
+  ? LayoutConformance
+  : UnimplementedLayoutConformance) as component(...LayoutConformanceProps);
+
+const styles = StyleSheet.create({
+  container: {
+    display: 'contents',
+  },
+});

node_modules/react-native/Libraries/Components/LayoutConformance/LayoutConformanceNativeComponent.js

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+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ */
+
+import type {HostComponent} from '../../../src/private/types/HostComponent';
+import type {ViewProps} from '../View/ViewPropTypes';
+
+import * as NativeComponentRegistry from '../../NativeComponent/NativeComponentRegistry';
+
+type Props = $ReadOnly<{
+  mode: 'strict' | 'compatibility',
+  ...ViewProps,
+}>;
+
+const LayoutConformanceNativeComponent: HostComponent<Props> =
+  NativeComponentRegistry.get<Props>('LayoutConformance', () => ({
+    uiViewClassName: 'LayoutConformance',
+    validAttributes: {
+      mode: true,
+    },
+  }));
+
+export default LayoutConformanceNativeComponent;