ImageCachePolicyTest.js

/**
 * Copyright (c) 2015-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 *
 * @flow
 * @providesModule ImageCachePolicyTest
 */
'use strict';

var React = require('react');
var ReactNative = require('react-native');
var {
  Image,
  View,
  Text,
  StyleSheet,
} = ReactNative;
var { TestModule } = ReactNative.NativeModules;

/*
 * The reload and force-cache tests don't actually verify that the complete functionality.
 *
 * reload: Should have the server set a long cache header, then swap the image on next load
 * with the test comparing the old image to the new image and making sure they are different.
 *
 * force-cache: Should do the above but set a no-cache header. The test should compare the first
 * image with the new one and make sure they are the same.
 */

const TESTS = ['only-if-cached', 'default', 'reload', 'force-cache'];

type Props = {}
type State = {
  'only-if-cached'?: boolean,
  'default'?: boolean,
  'reload'?: boolean,
  'force-cache'?: boolean,
}

class ImageCachePolicyTest extends React.Component {
  state = {}

  shouldComponentUpdate(nextProps: Props, nextState: State) {
    const results: Array<?boolean> = TESTS.map(x => nextState[x]);

    if (!results.includes(undefined)) {
      const result: boolean = results.reduce((x,y) => x === y === true, true)
      TestModule.markTestPassed(result);
    }

    return false;
  }

  testComplete(name: string, pass: boolean) {
    this.setState({[name]: pass});
  }

  render() {
    return (
      <View style={{flex: 1}}>
        <Text>Hello</Text>
      <Image
        source={{
              uri: 'https://facebook.github.io/react/img/logo_small_2x.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://facebook.github.io/react/img/logo_small_2x.png?cacheBust=notinCache' + Date.now(),
              cache: 'default'
            }}
          onLoad={() => this.testComplete('default', true)}
          onError={() => this.testComplete('default', false)}
          style={styles.base}
        />
        <Image
          source={{
              uri: 'https://facebook.github.io/react/img/logo_small_2x.png?cacheBust=notinCache' + Date.now(),
              cache: 'reload'
            }}
          onLoad={() => this.testComplete('reload', true)}
          onError={() => this.testComplete('reload', false)}
          style={styles.base}
        />
        <Image
          source={{
              uri: 'https://facebook.github.io/react/img/logo_small_2x.png?cacheBust=notinCache' + Date.now(),
              cache: 'force-cache'
            }}
          onLoad={() => this.testComplete('force-cache', true)}
          onError={() => this.testComplete('force-cache', false)}
          style={styles.base}
        />
      </View>
    );
  }
}

const styles = StyleSheet.create({
  base: {
    width: 100,
    height: 100,
  },
});

ImageCachePolicyTest.displayName = 'ImageCachePolicyTest';

module.exports = ImageCachePolicyTest;