text: /**
   * Copyright (c) 2015-present, Facebook, Inc.
   *
   * This source code is licensed under the MIT license found in the
   * LICENSE file in the root directory of this source tree.
   *
   * @flow
   * @providesModule AsyncStorageTest
   */
  'use strict';
  
  var React = require('react');
  var ReactNative = require('react-native');
  var {
    AsyncStorage,
    Text,
    View,
  } = ReactNative;
  var { TestModule } = ReactNative.NativeModules;
  
  var deepDiffer = require('../Libraries/Utilities/differ/deepDiffer');
  
  var DEBUG = false;
  
  var KEY_1 = 'key_1';
  var VAL_1 = 'val_1';
  var KEY_2 = 'key_2';
  var VAL_2 = 'val_2';
  var KEY_MERGE = 'key_merge';
  var VAL_MERGE_1 = {'foo': 1, 'bar': {'hoo': 1, 'boo': 1}, 'moo': {'a': 3}};
  var VAL_MERGE_2 = {'bar': {'hoo': 2}, 'baz': 2, 'moo': {'a': 3}};
  var VAL_MERGE_EXPECT =
    {'foo': 1, 'bar': {'hoo': 2, 'boo': 1}, 'baz': 2, 'moo': {'a': 3}};
  
  // setup in componentDidMount
  var done = (result : ?boolean) => {};
  var updateMessage = (message : string ) => {};
  
  function runTestCase(description : string, fn) {
    updateMessage(description);
    fn();
  }
  
  function expectTrue(condition : boolean, message : string) {
    if (!condition) {
      throw new Error(message);
    }
  }
  
  function expectEqual(lhs, rhs, testname : string) {
    expectTrue(
      !deepDiffer(lhs, rhs),
      'Error in test ' + testname + ': expected\n' + JSON.stringify(rhs) +
        '\ngot\n' + JSON.stringify(lhs)
    );
  }
  
  function expectAsyncNoError(place, err) {
    if (err instanceof Error) {
      err = err.message;
    }
    expectTrue(err === null, 'Unexpected error in ' + place + ': ' + JSON.stringify(err));
  }
  
  function testSetAndGet() {
    AsyncStorage.setItem(KEY_1, VAL_1, (err1) => {
      expectAsyncNoError('testSetAndGet/setItem', err1);
      AsyncStorage.getItem(KEY_1, (err2, result) => {
        expectAsyncNoError('testSetAndGet/getItem', err2);
        expectEqual(result, VAL_1, 'testSetAndGet setItem');
        updateMessage('get(key_1) correctly returned ' + result);
        runTestCase('should get null for missing key', testMissingGet);
      });
    });
  }
  
  function testMissingGet() {
    AsyncStorage.getItem(KEY_2, (err, result) => {
      expectAsyncNoError('testMissingGet/setItem', err);
      expectEqual(result, null, 'testMissingGet');
      updateMessage('missing get(key_2) correctly returned ' + result);
      runTestCase('check set twice results in a single key', testSetTwice);
    });
  }
  
  function testSetTwice() {
    AsyncStorage.setItem(KEY_1, VAL_1, ()=>{
      AsyncStorage.setItem(KEY_1, VAL_1, ()=>{
        AsyncStorage.getItem(KEY_1, (err, result) => {
          expectAsyncNoError('testSetTwice/setItem', err);
          expectEqual(result, VAL_1, 'testSetTwice');
          updateMessage('setTwice worked as expected');
          runTestCase('test removeItem', testRemoveItem);
        });
      });
    });
  }
  
  function testRemoveItem() {
    AsyncStorage.setItem(KEY_1, VAL_1, ()=>{
      AsyncStorage.setItem(KEY_2, VAL_2, ()=>{
        AsyncStorage.getAllKeys((err, result) => {
          expectAsyncNoError('testRemoveItem/getAllKeys', err);
          expectTrue(
            result.indexOf(KEY_1) >= 0 && result.indexOf(KEY_2) >= 0,
            'Missing KEY_1 or KEY_2 in ' + '(' + result + ')'
          );
          updateMessage('testRemoveItem - add two items');
          AsyncStorage.removeItem(KEY_1, (err2) => {
            expectAsyncNoError('testRemoveItem/removeItem', err2);
            updateMessage('delete successful ');
            AsyncStorage.getItem(KEY_1, (err3, result2) => {
              expectAsyncNoError('testRemoveItem/getItem', err3);
              expectEqual(
                result2,
                null,
                'testRemoveItem: key_1 present after delete'
              );
              updateMessage('key properly removed ');
              AsyncStorage.getAllKeys((err4, result3) => {
               expectAsyncNoError('testRemoveItem/getAllKeys', err4);
               expectTrue(
                 result3.indexOf(KEY_1) === -1,
                 'Unexpected: KEY_1 present in ' + result3
               );
               updateMessage('proper length returned.');
               runTestCase('should merge values', testMerge);
              });
            });
          });
        });
      });
    });
  }
  
  function testMerge() {
    AsyncStorage.setItem(KEY_MERGE, JSON.stringify(VAL_MERGE_1), (err1) => {
      expectAsyncNoError('testMerge/setItem', err1);
      AsyncStorage.mergeItem(KEY_MERGE, JSON.stringify(VAL_MERGE_2), (err2) => {
        expectAsyncNoError('testMerge/mergeItem', err2);
        AsyncStorage.getItem(KEY_MERGE, (err3, result) => {
          expectAsyncNoError('testMerge/setItem', err3);
          expectEqual(JSON.parse(result), VAL_MERGE_EXPECT, 'testMerge');
          updateMessage('objects deeply merged\nDone!');
          runTestCase('multi set and get', testOptimizedMultiGet);
        });
      });
    });
  }
  
  function testOptimizedMultiGet() {
    let batch = [[KEY_1, VAL_1], [KEY_2, VAL_2]];
    let keys = batch.map(([key, value]) => key);
    AsyncStorage.multiSet(batch, (err1) => {
      // yes, twice on purpose
      [1, 2].forEach((i) => {
        expectAsyncNoError(`${i} testOptimizedMultiGet/multiSet`, err1);
        AsyncStorage.multiGet(keys, (err2, result) => {
          expectAsyncNoError(`${i} testOptimizedMultiGet/multiGet`, err2);
          expectEqual(result, batch, `${i} testOptimizedMultiGet multiGet`);
          updateMessage('multiGet([key_1, key_2]) correctly returned ' + JSON.stringify(result));
          done();
        });
      });
    });
  }
  
  
  class AsyncStorageTest extends React.Component<{}, $FlowFixMeState> {
    state = {
      messages: 'Initializing...',
      done: false,
    };
  
    componentDidMount() {
      done = () => this.setState({done: true}, () => {
        TestModule.markTestCompleted();
      });
      updateMessage = (msg) => {
        this.setState({messages: this.state.messages.concat('\n' + msg)});
        DEBUG && console.log(msg);
      };
      AsyncStorage.clear(testSetAndGet);
    }
  
    render() {
      return (
        <View style={{backgroundColor: 'white', padding: 40}}>
          <Text>
            {
              /* $FlowFixMe(>=0.54.0 site=react_native_fb,react_native_oss) This
               * comment suppresses an error found when Flow v0.54 was deployed.
               * To see the error delete this comment and run Flow. */
              this.constructor.displayName + ': '}
            {this.state.done ? 'Done' : 'Testing...'}
            {'\n\n' + this.state.messages}
          </Text>
        </View>
      );
    }
  }
  
  AsyncStorageTest.displayName = 'AsyncStorageTest';
  
  module.exports = AsyncStorageTest;
  