signIn.js

import React, { useContext } from 'react';
import { LoginContext } from "contexts/LoginContext";

...

const signIn = async values => {
    const loginContext = useContext(LoginContext);
    try {
      const { email, password } = values;
      loginContext.actions.loginLoading();
      // Logs the user in...
      const { token, ...userData } = await authenticate(
        email,
        password
      );
      // Sets the login user token in the local storage
      await AsyncStorage.setItem('userToken', token);
      // Updates the contexts related to the login
      loginContext.actions.login(token);
    } catch (error) {
      // Logs the user out
      loginContext.actions.logout();
    }
  };
  
export default signIn;