Files
medusa-store/integration-tests/api/__tests__/totals/orders.js
Sebastian Rindom 39f2c0c15e fix(medusa): calculates correct taxes and totals on order with gift cards (#1807)
**What**
Since the release of the Tax API the line item totals calculations on orders with gift cards have been wrong. To understand the bug consider the below order:

Region:
- tax_rate: 25%
- gift_cards_taxable: true

Order:
- applied gift card: 1000
- items: 
  - A: unit_price: 1000
  - B: unit_price: 500
- Subtotal: 1500

**Previous calculation method**
1. Determine how much of the gift card is used for each item using `item_total / subtotal * gift_card_amount`:
  - Item A: 1000/1500 * 1000 = 666.67
  - Item B: 500/1500 * 1000 = 333.33
2. Calculate line item totals including taxes using `(unit_price - gift_card) * (1 + tax_rate)`
  - Item A: 1000 - 666.67 = 333.33; vat amount -> 83.33
  - Item B: 500 - 333.33 = 166.67; vat amount -> 41.67
3. Add up the line item totals: order subtotal = 500; vat amount = 125; total = 625

This is all correct at the totals level; but at the line item level we should still use the "original prices" i.e. the line item total for item a should be (1000 * 1.25) = 1250 with a tax amount of 250. 

**New calculation method**
1. Use default totals calculations
  - Item A: subtotal: 1000, tax_total: 250, total: 1250
  - Item B: subtotal: 500, tax_total: 125, total: 625
2. Add up the line item totals: subtotal: 1500, tax_total: 375, total: 1875
3. Reduce total with gift card: subtotal: 1500 - 1000 = 500, tax_total: 375 - 250 = 125, total = 625

Totals can now be forwarded correctly to accounting plugins.

Fixes CORE-310.
2022-07-11 12:18:43 +00:00

171 lines
4.7 KiB
JavaScript

const path = require("path")
const setupServer = require("../../../helpers/setup-server")
const { useApi } = require("../../../helpers/use-api")
const { initDb, useDb } = require("../../../helpers/use-db")
const adminSeeder = require("../../helpers/admin-seeder")
const {
simpleRegionFactory,
simpleCartFactory,
simpleGiftCardFactory,
simpleProductFactory,
} = require("../../factories")
jest.setTimeout(30000)
describe("Order Totals", () => {
let medusaProcess
let dbConnection
const doAfterEach = async () => {
const db = useDb()
return await db.teardown()
}
beforeAll(async () => {
const cwd = path.resolve(path.join(__dirname, "..", ".."))
try {
dbConnection = await initDb({ cwd })
medusaProcess = await setupServer({ cwd })
} catch (error) {
console.log(error)
}
})
afterAll(async () => {
const db = useDb()
await db.shutdown()
medusaProcess.kill()
})
afterEach(async () => {
return await doAfterEach()
})
test("calculates totals correctly for order with non-taxable gift card", async () => {
await adminSeeder(dbConnection)
await simpleProductFactory(dbConnection, {
variants: [
{ id: "variant_1", prices: [{ currency: "usd", amount: 95600 }] },
{ id: "variant_2", prices: [{ currency: "usd", amount: 79600 }] },
],
})
const region = await simpleRegionFactory(dbConnection, {
gift_cards_taxable: false,
tax_rate: 25,
})
const cart = await simpleCartFactory(dbConnection, {
id: "test-cart",
email: "testnation@medusajs.com",
region: region.id,
line_items: [],
})
const giftCard = await simpleGiftCardFactory(dbConnection, {
region_id: region.id,
value: 160000,
balance: 160000,
})
const api = useApi()
await api.post("/store/carts/test-cart/line-items", {
quantity: 1,
variant_id: "variant_1",
})
await api.post("/store/carts/test-cart/line-items", {
quantity: 1,
variant_id: "variant_2",
})
await api.post("/store/carts/test-cart", {
gift_cards: [{ code: giftCard.code }],
})
await api.post(`/store/carts/${cart.id}/payment-sessions`)
const response = await api.post(`/store/carts/test-cart/complete`)
expect(response.status).toEqual(200)
expect(response.data.type).toEqual("order")
const orderId = response.data.data.id
const { data } = await api.get(`/admin/orders/${orderId}`, {
headers: { Authorization: `Bearer test_token` },
})
expect(data.order.gift_card_transactions).toEqual([
expect.objectContaining({
amount: 160000,
is_taxable: false,
tax_rate: null,
}),
])
expect(data.order.gift_card_total).toEqual(160000)
expect(data.order.gift_card_tax_total).toEqual(0)
expect(data.order.total).toEqual(59000)
})
test("calculates totals correctly for order with taxable gift card", async () => {
await adminSeeder(dbConnection)
await simpleProductFactory(dbConnection, {
variants: [
{ id: "variant_1", prices: [{ currency: "usd", amount: 95600 }] },
{ id: "variant_2", prices: [{ currency: "usd", amount: 79600 }] },
],
})
const region = await simpleRegionFactory(dbConnection, {
gift_cards_taxable: true,
tax_rate: 25,
})
const cart = await simpleCartFactory(dbConnection, {
id: "test-cart",
email: "testnation@medusajs.com",
region: region.id,
line_items: [],
})
const giftCard = await simpleGiftCardFactory(dbConnection, {
region_id: region.id,
value: 160000,
balance: 160000,
})
const api = useApi()
await api.post("/store/carts/test-cart/line-items", {
quantity: 1,
variant_id: "variant_1",
})
await api.post("/store/carts/test-cart/line-items", {
quantity: 1,
variant_id: "variant_2",
})
await api.post("/store/carts/test-cart", {
gift_cards: [{ code: giftCard.code }],
})
await api.post(`/store/carts/${cart.id}/payment-sessions`)
const response = await api.post(`/store/carts/test-cart/complete`)
expect(response.status).toEqual(200)
expect(response.data.type).toEqual("order")
const orderId = response.data.data.id
const { data } = await api.get(`/admin/orders/${orderId}`, {
headers: { Authorization: `Bearer test_token` },
})
expect(data.order.gift_card_transactions).toEqual([
expect.objectContaining({
amount: 160000,
is_taxable: true,
tax_rate: 25,
}),
])
expect(data.order.gift_card_total).toEqual(160000)
expect(data.order.gift_card_tax_total).toEqual(40000)
expect(data.order.tax_total).toEqual(3800)
expect(data.order.total).toEqual(19000)
})
})