todo.spec.js

'use strict'

const ToDo = require('../modules/todo.js')

beforeAll( async() => {
	// stuff to do before any of the tests run
})

afterAll( async() => {
	// runs after all the tests have completed
})

describe('add()', () => {
	// block of tests
	// beforeEach( async() => {
	// 	todo.clear()
	// })
	afterEach( async() => {
		// runs after each test completes
	})
	test('add a single item', async done => {
		expect.assertions(1)
		// ARRANGE
		const todo = await new ToDo() // DB runs in-memory if no name supplied
		// ACT
		await todo.add('bread', 3)
		const count = await todo.countItems()
		// ASSERT
		expect(count).toBe(1)
		done()
	})

	test('qty must be a number', async done => {
		expect.assertions(1)
		const todo = await new ToDo()
		await expect( todo.add('bread', 'three') ).rejects.toEqual( Error('the quantity must be a number') )
		done()
	})

	test('duplicates should increase qty', async done => {
		expect.assertions(2)
		// ARRANGE
		const todo = await new ToDo()
		// ACT
		await todo.add('bread', 4)
		await todo.add('bread', 2)
		const data = await todo.getAll()
		const qty = data[0].qty
		// ASSERT (note there are two assertions as stated on line 42)
		expect(data).toHaveLength(1)
		expect(qty).toEqual(6)
		done()
	})

	test('item cannot be empty', async done => {
		expect.assertions(1)
		const todo = await new ToDo()
		await expect( todo.add('', 1) ).rejects.toEqual( Error('item cannot be empty') )
		done()
	})

	test('qty cannot be empty', async done => {
		expect.assertions(1)
		const todo = await new ToDo()
		await expect( todo.add('bread', '') ).rejects.toEqual( Error('qty cannot be empty') )
		done()
	})

})

describe('delete()', () => {
	beforeEach( async() => {
		this.todo = await new ToDo()
		await this.todo.add('bread', 5)
	})
	
	test('id cannot be undefined', async done => {
		expect.assertions(1)
		await expect( this.todo.delete() ).rejects.toEqual( Error('id cannot be undefined') )
		done()
	})

	test('id must be a number', async done => {
		expect.assertions(1)
		await expect( this.todo.delete('a') ).rejects.toEqual( Error('id must be a number') )
		done()
	})

	test('id has to exist', async done => {
		expect.assertions(1)
		await expect( this.todo.delete(2) ).rejects.toEqual( Error('id has to exist') )
		done()
	})

	test('delete an item', async done => {
		expect.assertions(2)
		await this.todo.delete(1)
		expect(await this.todo.countItems()).toEqual(0)
		expect(await this.todo.getAll()).toEqual([])
		done()
	})
})

describe('getAll()', () => {
	beforeEach( async() => {
		this.todo = await new ToDo()
	})

	test('getAll() with no items', async done => {
		expect.assertions(1)
		expect(await this.todo.getAll()).toEqual([])
		done()
	})

	test('getAll() with a single item', async done => {
		expect.assertions(1)
		await this.todo.add('bread', 2)
		expect(await this.todo.getAll()).toEqual([{"item":"bread", "qty":2, "id":1}])
		done()
	})

	test('getAll() with two items', async done => {
		expect.assertions(1)
		await this.todo.add('bread', 2)
		await this.todo.add('ham', 3)
		expect(await this.todo.getAll()).toEqual([{"item":"bread", "qty":2, "id":1}, {"item":"ham", "qty":3, "id":2}])
		done()
	})
})

describe('clear()', () => {
	beforeEach( async() => {
		this.todo = await new ToDo()
	})

	test('clear() with no items', async done => {
		expect.assertions(2)
		await this.todo.clear()
		expect(await this.todo.countItems()).toEqual(0)
		expect(await this.todo.getAll()).toEqual([])
		done()
	})

	test('clear() with a single item', async done => {
		expect.assertions(2)
		await this.todo.add('bread', 2)
		await this.todo.clear()
		expect(await this.todo.countItems()).toEqual(0)
		expect(await this.todo.getAll()).toEqual([])
		done()
	})

	test('clear() with two items', async done => {
		expect.assertions(2)
		await this.todo.add('bread', 2)
		await this.todo.add('ham', 3)
		await this.todo.clear()
		expect(await this.todo.countItems()).toEqual(0)
		expect(await this.todo.getAll()).toEqual([])
		done()
	})
})