fix RCTNetInfo first time connection status

[karanjthakkar]

Fixes #20804, #8615, #18368 (comment)

Test Plan:

1. Works without connectionChange event listener

Test Code:

import React, {Component} from 'react';
import {Platform, StyleSheet, Text, View, NetInfo} from 'react-native';

export default class App extends Component {
  state = {
    isConnected: false
  };

  componentWillMount() {
    NetInfo.isConnected.fetch().then(isConnected => {
      this.setState({
        isConnected
      });
    });
  }

  render() {
    return (
      <View style={styles.container}>
        <Text>{`isConnected: ${this.state.isConnected}`}</Text>
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
});

The code shown above will now return the right connection status. If you're connected to Wifi or cellular, it will return true, else false. Previously, it always returned false for the first time.

2. Works with connectionChange event listener

Test Code:

import React, {Component} from 'react';
import {Platform, StyleSheet, Text, View, NetInfo} from 'react-native';

export default class App extends Component {
  state = {
    isConnected: false
  };

  componentWillMount() {
    NetInfo.isConnected.fetch().then(isConnected => {
      this.setState({
        isConnected
      });
    });
    const handleFirstConnectivityChange = (isConnected) => {
      this.setState({
        isConnected
      });
    }
    NetInfo.isConnected.addEventListener(
      'connectionChange',
      handleFirstConnectivityChange
    );
  }

  render() {
    return (
      <View style={styles.container}>
        <Text>{`isConnected: ${this.state.isConnected}`}</Text>
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: '#F5FCFF',
  },
});

The change done in this PR does not create any regression in the event listener flow. This still works perfectly fine.

Release Notes:

[IOS] [BUGFIX] [NETINFO] - fixes RCTNetInfo incorrect first time connection status

[karanjthakkar]

I don't understand why the tests are failing. The logs seem to be unrelated to the changes made in this PR. Maybe someone else knows what the issue is?

[karanjthakkar]

cc: @hramos, can you help here? 🙂

[facebook-github-bot]

hramos is landing this pull request. If you are a Facebook employee, you can view this diff on Phabricator.

[react-native-bot]

@karanjthakkar merged commit 36199d3 into facebook:master.

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Once this commit is added to a release, you will see the corresponding version tag below the description at 36199d3. If the commit has a single master tag, it is not yet part of a release.