TypeError: Cannot read property 'SHORT' of undefined

Question

I am writing unit tests for react native app using jest and enzyme. When I try to run the test cases I get the following error:

● Test suite failed to run

TypeError: Cannot read property 'SHORT' of undefined

at Object. (node_modules/react-native-simple-toast/index.js:7:23) at Object. (src/client/components/Catalogue/events.js:10:29) at Object. (tests/events-test.js:5:13) at Generator.next () at new Promise () at Generator.next () at

The error is due to importing Toast from react-native-simple-toast. Without this import the test runs fine, but I need react-native-simple-toast in my component and hence cannot remove it.I somehow need the test to run with react-native-simple-toast in my component:

import React, { Component } from 'react'
import { Platform, ActivityIndicator, Linking, Dimensions, View, Text, 
TouchableOpacity, TextInput, StyleSheet, Keyboard, Image, 
KeyboardAvoidingView } from 'react-native'
import { Container, Header, Card, CardItem, Content, Left, Right, Body, 
Title, Icon, Button } from 'native-base';
import IconIOSback from 'react-native-vector-icons/Ionicons';
import IconMenu from 'react-native-vector-icons/MaterialIcons';
import axios from 'axios';
import SERVER_URL from '../../config';
import { Col, Row, Grid } from 'react-native-easy-grid';
import Toast from 'react-native-simple-toast';   //this causes the error

Kindly, help me resolve this issue.

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Ash Ash · Accepted Answer · 2019-02-27T07:45:24

to get a way around this is to mock the property SHORT. Create a test setup file eg setup.js and include the following mock

jest.mock('react-native-simple-toast', () => ({
  SHORT: jest.fn(),
}));

Ensure to add this file in your package.json under jest configuration ie

"jest": 
.....
"setupFiles": [
      "/setup.js" // location of your setup.js file
    ]

TypeError: Cannot read property 'SHORT' of undefined

3 Answers