Remove var in RNTester (#22019)

Summary:
I removed `var` in RNTester.

- [x] npm run prettier
- [x] npm run flow-check-ios
- [x] npm run flow-check-android

[GENERAL] [ENHANCEMENT] [RNTester] - remove `var`
Pull Request resolved: https://github.com/facebook/react-native/pull/22019

Differential Revision: D12843071

Pulled By: TheSavior

fbshipit-source-id: 3652ea91b3ab92c367332cbe2ff7de0343508dad

RNTester/js/ARTExample.js

@@ -10,13 +10,13 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {ART, Platform, View} = ReactNative;
+const React = require('react');
+const ReactNative = require('react-native');
+const {ART, Platform, View} = ReactNative;
 
 const {Surface, Path, Group, Transform, Shape} = ART;
 
-var scale = Platform.isTV ? 4 : 1;
+const scale = Platform.isTV ? 4 : 1;
 
 class ARTExample extends React.Component<{}> {
   render() {

RNTester/js/AccessibilityAndroidExample.android.js

@@ -9,9 +9,9 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {
+const React = require('react');
+const ReactNative = require('react-native');
+const {
   AccessibilityInfo,
   StyleSheet,
   Text,
@@ -20,10 +20,10 @@ var {
   TouchableWithoutFeedback,
 } = ReactNative;
 
-var RNTesterBlock = require('./RNTesterBlock');
-var RNTesterPage = require('./RNTesterPage');
+const RNTesterBlock = require('./RNTesterBlock');
+const RNTesterPage = require('./RNTesterPage');
 
-var importantForAccessibilityValues = [
+const importantForAccessibilityValues = [
   'auto',
   'yes',
   'no',
@@ -293,7 +293,7 @@ class AccessibilityAndroidExample extends React.Component {
   }
 }
 
-var styles = StyleSheet.create({
+const styles = StyleSheet.create({
   embedded: {
     backgroundColor: 'yellow',
     padding: 10,

RNTester/js/AccessibilityIOSExample.js

@@ -10,9 +10,9 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {AccessibilityInfo, Text, View, TouchableOpacity} = ReactNative;
+const React = require('react');
+const ReactNative = require('react-native');
+const {AccessibilityInfo, Text, View, TouchableOpacity} = ReactNative;
 
 class AccessibilityIOSExample extends React.Component<{}> {
   render() {

RNTester/js/ActionSheetIOSExample.js

@@ -10,13 +10,13 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {ActionSheetIOS, StyleSheet, takeSnapshot, Text, View} = ReactNative;
+const React = require('react');
+const ReactNative = require('react-native');
+const {ActionSheetIOS, StyleSheet, takeSnapshot, Text, View} = ReactNative;
 
-var BUTTONS = ['Option 0', 'Option 1', 'Option 2', 'Delete', 'Cancel'];
-var DESTRUCTIVE_INDEX = 3;
-var CANCEL_INDEX = 4;
+const BUTTONS = ['Option 0', 'Option 1', 'Option 2', 'Delete', 'Cancel'];
+const DESTRUCTIVE_INDEX = 3;
+const CANCEL_INDEX = 4;
 
 class ActionSheetExample extends React.Component<{}, $FlowFixMeState> {
   state = {
@@ -108,7 +108,7 @@ class ShareActionSheetExample extends React.Component<
       },
       error => alert(error),
       (completed, method) => {
-        var text;
+        let text;
         if (completed) {
           text = `Shared via ${method}`;
         } else {
@@ -148,7 +148,7 @@ class ShareScreenshotExample extends React.Component<{}, $FlowFixMeState> {
           },
           error => alert(error),
           (completed, method) => {
-            var text;
+            let text;
             if (completed) {
               text = `Shared via ${method}`;
             } else {
@@ -162,7 +162,7 @@ class ShareScreenshotExample extends React.Component<{}, $FlowFixMeState> {
   };
 }
 
-var style = StyleSheet.create({
+const style = StyleSheet.create({
   button: {
     marginBottom: 10,
     fontWeight: '500',

RNTester/js/AlertExample.js

@@ -9,14 +9,14 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {Alert, StyleSheet, Text, TouchableHighlight, View} = ReactNative;
+const React = require('react');
+const ReactNative = require('react-native');
+const {Alert, StyleSheet, Text, TouchableHighlight, View} = ReactNative;
 
-var RNTesterBlock = require('./RNTesterBlock');
+const RNTesterBlock = require('./RNTesterBlock');
 
 // corporate ipsum > lorem ipsum
-var alertMessage =
+const alertMessage =
   'Credibly reintermediate next-generation potentialities after goal-oriented ' +
   'catalysts for change. Dynamically revolutionize.';
 
@@ -134,7 +134,7 @@ class AlertExample extends React.Component {
   }
 }
 
-var styles = StyleSheet.create({
+const styles = StyleSheet.create({
   wrapper: {
     borderRadius: 5,
     marginBottom: 5,

RNTester/js/AlertIOSExample.js

@@ -10,11 +10,11 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {StyleSheet, View, Text, TouchableHighlight, AlertIOS} = ReactNative;
+const React = require('react');
+const ReactNative = require('react-native');
+const {StyleSheet, View, Text, TouchableHighlight, AlertIOS} = ReactNative;
 
-var {SimpleAlertExampleBlock} = require('./AlertExample');
+const {SimpleAlertExampleBlock} = require('./AlertExample');
 
 exports.framework = 'React';
 exports.title = 'AlertIOS';
@@ -180,7 +180,7 @@ class PromptOptions extends React.Component<$FlowFixMeProps, any> {
   }
 }
 
-var styles = StyleSheet.create({
+const styles = StyleSheet.create({
   wrapper: {
     borderRadius: 5,
     marginBottom: 5,

RNTester/js/AnimatedExample.js

@@ -10,10 +10,10 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {Animated, Easing, StyleSheet, Text, View} = ReactNative;
-var RNTesterButton = require('./RNTesterButton');
+const React = require('react');
+const ReactNative = require('react-native');
+const {Animated, Easing, StyleSheet, Text, View} = ReactNative;
+const RNTesterButton = require('./RNTesterButton');
 
 exports.framework = 'React';
 exports.title = 'Animated - Examples';
@@ -158,7 +158,7 @@ exports.examples = [
         <View>
           <RNTesterButton
             onPress={() => {
-              var timing = Animated.timing;
+              const timing = Animated.timing;
               Animated.sequence([
                 // One after the other
                 timing(this.anims[0], {
@@ -285,7 +285,7 @@ exports.examples = [
   },
 ];
 
-var styles = StyleSheet.create({
+const styles = StyleSheet.create({
   content: {
     backgroundColor: 'deepskyblue',
     borderWidth: 1,

RNTester/js/AppStateExample.js

@@ -39,7 +39,7 @@ class AppStateSubscription extends React.Component<
   };
 
   _handleAppStateChange = appState => {
-    var previousAppStates = this.state.previousAppStates.slice();
+    const previousAppStates = this.state.previousAppStates.slice();
     previousAppStates.push(this.state.appState);
     this.setState({
       appState,

RNTester/js/AssetScaledImageExample.js

@@ -10,9 +10,9 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {Image, StyleSheet, View, ScrollView} = ReactNative;
+const React = require('react');
+const ReactNative = require('react-native');
+const {Image, StyleSheet, View, ScrollView} = ReactNative;
 
 import type {PhotoIdentifier} from 'CameraRoll';
 
@@ -30,7 +30,7 @@ class AssetScaledImageExample extends React.Component<Props, State> {
   };
 
   render() {
-    var image = this.state.asset.node.image;
+    const image = this.state.asset.node.image;
     return (
       <ScrollView>
         <View style={styles.row}>
@@ -50,7 +50,7 @@ class AssetScaledImageExample extends React.Component<Props, State> {
   }
 }
 
-var styles = StyleSheet.create({
+const styles = StyleSheet.create({
   row: {
     padding: 5,
     flex: 1,

RNTester/js/AsyncStorageExample.js

@@ -10,13 +10,13 @@
 
 'use strict';
 
-var React = require('react');
-var ReactNative = require('react-native');
-var {AsyncStorage, PickerIOS, Text, View} = ReactNative;
-var PickerItemIOS = PickerIOS.Item;
+const React = require('react');
+const ReactNative = require('react-native');
+const {AsyncStorage, PickerIOS, Text, View} = ReactNative;
+const PickerItemIOS = PickerIOS.Item;
 
-var STORAGE_KEY = '@AsyncStorageExample:key';
-var COLORS = ['red', 'orange', 'yellow', 'green', 'blue'];
+const STORAGE_KEY = '@AsyncStorageExample:key';
+const COLORS = ['red', 'orange', 'yellow', 'green', 'blue'];
 
 class BasicStorageExample extends React.Component<{}, $FlowFixMeState> {
   state = {
@@ -30,7 +30,7 @@ class BasicStorageExample extends React.Component<{}, $FlowFixMeState> {
 
   _loadInitialState = async () => {
     try {
-      var value = await AsyncStorage.getItem(STORAGE_KEY);
+      const value = await AsyncStorage.getItem(STORAGE_KEY);
       if (value !== null) {
         this.setState({selectedValue: value});
         this._appendMessage('Recovered selection from disk: ' + value);
@@ -43,7 +43,7 @@ class BasicStorageExample extends React.Component<{}, $FlowFixMeState> {
   };
 
   render() {
-    var color = this.state.selectedValue;
+    const color = this.state.selectedValue;
     return (
       <View>
         <PickerIOS selectedValue={color} onValueChange={this._onValueChange}>