interface ISomeObj {
  percentage: string;
}
export const makeSomeObj = () => {
  return {
    percentage: Math.random()
  };
}

// This file is "src/pages/newYorkInfo.tsx"
import * as React from 'react';
interface IUser {
    state: string;
    address: string;
    isAdmin: boolean;
    deleted: boolean | undefined;
}
export const NewYorkUserPage: React.FunctionComponent<{ user: IUser }> = props => {
    if (props.user.state === 'NY' && !props.user.deleted) {
        const welcomeMessage = `Welcome`;
        return <h1 id="ny-dashboard">{welcomeMessage}</h1>;
    } else {
        return <div>ACCESS DENIED</div>;
    }
};

// fixtures/user.json
{
    state: 'NY',
    isAdmin: true,
    address: '55 Main St',
}

// When the UI calls the user endpoint, return the JSON as the mocked return value
cy.route('GET', '/user/**', 'fixture:user.json');
cy.visit('/dashboard');
cy.get('#ny-dashboard').should('exist')

// This file is "src/pages/newYorkInfo.tsx"
import * as React from 'react';
interface IUser {
    name: string;
    state: string;
    address: string;
    isAdmin: boolean;
    deleted: boolean | undefined;
}
export const NewYorkUserPage: React.FunctionComponent<{ user: IUser }> = props => {
    if (props.user.state === 'NY' && !props.user.deleted) {
        const welcomeMessage = `Welcome ${props.user.name.toLowerCase()}!`;
        return <h1 id="ny-dashboard">{welcomeMessage}</h1>;
    } else {
        return <div>ACCESS DENIED</div>;
    }
};

Uncaught TypeError: Cannot read property 'toLowerCase' of undefined

// this file is "testData/users"
import {IUser} from 'src/pages/newYorkInfo';
// Property 'name' is missing in type '{ state: string; isAdmin: true; address: string; deleted: false; }' but required in type 'IUser'.ts(2741)
export const generalUser: IUser = {
    state: 'NY',
    isAdmin: true,
    address: '55 Main St',
    deleted: false,
};

import { generalUser } from 'testData/users';
// When the UI calls the user endpoint, return the JSON as the mocked return value
cy.route('GET', '/user/**', generalUser);
cy.visit('/dashboard');
cy.get('#ny-dashboard').should('exist')

// this file is "testData/users"
import {IUser} from 'src/pages/newYorkInfo';
export const nonAdminUser: IUser = {
    name: 'Bob',
    state: 'NY',
    isAdmin: false,
    address: '55 Main St',
    deleted: false,
};
export const adminUser: IUser = {
    name: 'Bob',
    state: 'NY',
    isAdmin: true,
    address: '55 Main St',
    deleted: false,
};
export const deletedAdminUser: IUser = {
    name: 'Bob',
    state: 'NY',
    isAdmin: true,
    address: '55 Main St',
    deleted: true,
};
export const deletedNonAdmin: IUser = {
    name: 'Bob',
    state: 'NY',
    isAdmin: false,
    address: '55 Main St',
    deleted: true,
};
// and on and on and on again...

// src/factories/user
import faker from 'faker';
import {IUser} from 'src/pages/newYorkInfo';
export const makeFakeUser = (): IUser => {
    return {
        name: faker.name.firstName() + ' ' + faker.name.lastName(),
        state: faker.address.stateAbbr(),
        isAdmin: faker.random.boolean(),
        address: faker.address.streetAddress(),
        deleted: faker.random.boolean(),
    }
}

import { makeFakeUser } from 'src/factories/user';
import {IUser} from 'src/pages/newYorkInfo';
// Arrange
const randomUser = makeFakeUser();
const deletedUser: IUser = { ...randomUser, ...{
  deleted: true
};
cy.route('GET', '/user/**', deletedUser);
// Act
cy.visit('/dashboard');
// Assert
cy.find('ACCESS DENIED').should('exist')

interface IUser {
    userName: string;
    preferences: {
        lastUpdated?: Date;
        favoriteColor?: string;
        backupContact?: string;
        mailingAddress: {
            street: string;
            city: string;
            state: string;
            zipCode: string;
        }
     }
}

const userOnMainSt = makeFakeUser({
    preferences: {
        mailingAddress: {
            street: 'Main Street'
        }
    }
});

const makeFakeUser = (override?: NestedPartial<IDeepObj>): IDeepObj => {
        const seed: IDeepObj = {
          userName: 'Bob Smith',
          preferences: {
            mailingAddress: {
              street: faker.address.streetAddress(),
              city: faker.address.city(),
              state: faker.address.stateAbbr(),
              zipCode: faker.address.zipCode(),
            },
          },
        };
        return mergePartially.deep(seed, override);
      };