Migrate rn-tester/IntegrationTests/ImageCachePolicyTest.js to functio…

…n components (facebook#48701)

Summary:
Pull Request resolved: facebook#48701

As per title.

Changelog: [Internal]

Reviewed By: rshest

Differential Revision: D68153254

fbshipit-source-id: 24789c814550cd592cb68a0576c5037088734a75

packages/rn-tester/IntegrationTests/ImageCachePolicyTest.js

@@ -10,10 +10,13 @@
 
 'use strict';
 
-const React = require('react');
-const ReactNative = require('react-native');
-const {Image, View, Text, StyleSheet} = ReactNative;
-const {TestModule} = ReactNative.NativeModules;
+import type {ImageURISource} from 'react-native/Libraries/Image/ImageSource';
+
+import * as React from 'react';
+import {useEffect, useState} from 'react';
+import {Image, NativeModules, StyleSheet, Text, View} from 'react-native';
+
+const {TestModule} = NativeModules;
 
 /*
  * The reload and force-cache tests don't actually verify that the complete functionality.
@@ -27,89 +30,71 @@ const {TestModule} = ReactNative.NativeModules;
 
 const TESTS = ['only-if-cached', 'default', 'reload', 'force-cache'];
 
-type Props = {...};
-type State = {
-  'only-if-cached'?: boolean,
-  default?: boolean,
-  reload?: boolean,
-  'force-cache'?: boolean,
-  ...
-};
+function ImageCachePolicyTest(): React.Node {
+  const [state, setState] = useState({
+    'only-if-cached': undefined,
+    default: undefined,
+    reload: undefined,
+    'force-cache': undefined,
+  });
 
-class ImageCachePolicyTest extends React.Component<Props, $FlowFixMeState> {
-  state: $FlowFixMe | {...} = {};
+  const testComplete = (
+    name: $NonMaybeType<ImageURISource['cache']>,
+    pass: boolean,
+  ) => {
+    setState(prevState => ({
+      ...prevState,
+      [name]: pass,
+    }));
+  };
 
-  shouldComponentUpdate(nextProps: Props, nextState: State): boolean {
-    const results: Array<?boolean> = TESTS.map(x => nextState[x]);
+  useEffect(() => {
+    const results = TESTS.map(key => state[key]);
 
     if (!results.includes(undefined)) {
-      const result: boolean = results.reduce(
-        (x, y) => (x === y) === true,
-        true,
-      );
+      const result = results.reduce((x, y) => (x === y) === true, true);
       TestModule.markTestPassed(result);
     }
+  }, [state]);
 
-    return false;
-  }
-
-  testComplete(name: string, pass: boolean) {
-    this.setState({[name]: pass});
-  }
-
-  render(): React.Node {
-    return (
-      <View style={styles.container}>
-        <Text>Hello</Text>
-        <Image
-          source={{
-            uri:
-              'https://raw.githubusercontent.com/facebook/react-native/HEAD/Libraries/NewAppScreen/components/logo.png?cacheBust=notinCache' +
-              Date.now(),
-            cache: 'only-if-cached',
-          }}
-          onLoad={() => this.testComplete('only-if-cached', false)}
-          onError={() => this.testComplete('only-if-cached', true)}
-          style={styles.base}
-        />
-        <Image
-          source={{
-            uri:
-              'https://raw.githubusercontent.com/facebook/react-native/HEAD/Libraries/NewAppScreen/components/logo.png?cacheBust=notinCache' +
-              Date.now(),
-            cache: 'default',
-          }}
-          onLoad={() => this.testComplete('default', true)}
-          onError={() => this.testComplete('default', false)}
-          style={styles.base}
-        />
-        <Image
-          source={{
-            uri:
-              'https://raw.githubusercontent.com/facebook/react-native/HEAD/Libraries/NewAppScreen/components/logo.png?cacheBust=notinCache' +
-              Date.now(),
-            cache: 'reload',
-          }}
-          onLoad={() => this.testComplete('reload', true)}
-          onError={() => this.testComplete('reload', false)}
-          style={styles.base}
-        />
-        <Image
-          source={{
-            uri:
-              'https://raw.githubusercontent.com/facebook/react-native/HEAD/Libraries/NewAppScreen/components/logo.png?cacheBust=notinCache' +
-              Date.now(),
-            cache: 'force-cache',
-          }}
-          onLoad={() => this.testComplete('force-cache', true)}
-          onError={() => this.testComplete('force-cache', false)}
-          style={styles.base}
-        />
-      </View>
-    );
-  }
+  return (
+    <View style={styles.container}>
+      <Text>Hello</Text>
+      <Image
+        source={getImageSource('only-if-cached')}
+        onLoad={() => testComplete('only-if-cached', false)}
+        onError={() => testComplete('only-if-cached', true)}
+        style={styles.base}
+      />
+      <Image
+        source={getImageSource('default')}
+        onLoad={() => testComplete('default', true)}
+        onError={() => testComplete('default', false)}
+        style={styles.base}
+      />
+      <Image
+        source={getImageSource('reload')}
+        onLoad={() => testComplete('reload', true)}
+        onError={() => testComplete('reload', false)}
+        style={styles.base}
+      />
+      <Image
+        source={getImageSource('force-cache')}
+        onLoad={() => testComplete('force-cache', true)}
+        onError={() => testComplete('force-cache', false)}
+        style={styles.base}
+      />
+    </View>
+  );
 }
 
+const getImageSource = (cache: ImageURISource['cache']) => ({
+  uri:
+    'https://raw.githubusercontent.com/facebook/react-native/HEAD/Libraries/NewAppScreen/components/logo.png?cacheBust=notinCache' +
+    Date.now(),
+  cache,
+});
+
 const styles = StyleSheet.create({
   container: {
     flex: 1,
@@ -120,6 +105,4 @@ const styles = StyleSheet.create({
   },
 });
 
-ImageCachePolicyTest.displayName = 'ImageCachePolicyTest';
-
-module.exports = ImageCachePolicyTest;
+export default ImageCachePolicyTest;