[Bug]: Promotions are applied randomly to line items

[opeah]

Package.json file

{
  "name": "@nexa/medusa",
  "version": "1.0.0",
  "scripts": {
    "build": "npx medusa build",
    "dev": "npx medusa develop",
    "predeploy": "npx medusa db:migrate",
    "seed": "npx medusa exec ./src/scripts/seed-layouts.ts && npx medusa exec ./src/scripts/seed-pages.ts && npx medusa exec ./src/scripts/seed-theme.ts",
    "start": "pnpm run predeploy && pnpm run seed && cd .medusa/server && npx medusa start -H 0.0.0.0"
  },
  "dependencies": {
    "@aws-sdk/client-s3": "3.556.0",
    "@dnd-kit/core": "6.2.0",
    "@dnd-kit/sortable": "9.0.0",
    "@dnd-kit/utilities": "3.2.2",
    "@lexical/html": "0.20.0",
    "@lexical/list": "0.20.0",
    "@lexical/react": "0.20.0",
    "@lexical/utils": "0.20.0",
    "@medusa/mappers": "workspace:^",
    "@medusa/models": "workspace:^",
    "@medusa/operations": "workspace:^",
    "@medusajs/admin-sdk": "catalog:medusa",
    "@medusajs/cli": "catalog:medusa",
    "@medusajs/framework": "catalog:medusa",
    "@medusajs/icons": "catalog:medusa",
    "@medusajs/medusa": "catalog:medusa",
    "@medusajs/ui": "catalog:medusa",
    "@mikro-orm/cli": "6.4.3",
    "@mikro-orm/core": "6.4.3",
    "@mikro-orm/knex": "6.4.3",
    "@mikro-orm/migrations": "6.4.3",
    "@mikro-orm/postgresql": "6.4.3",
    "@nebula/modules": "workspace:^",
    "@nexa/analytics": "workspace:^",
    "@nexa/domain": "workspace:^",
    "@nexa/http-client": "workspace:^",
    "@nexa/utils": "workspace:^",
    "@slack/types": "2.14.0",
    "@slack/web-api": "7.8.0",
    "@types/facebook-nodejs-business-sdk": "catalog:",
    "attr-accept": "2.2.2",
    "awilix": "8.0.1",
    "cheerio": "1.0.0",
    "class-variance-authority": "catalog:",
    "color": "4.2.3",
    "customerio-node": "4.1.1",
    "facebook-nodejs-business-sdk": "catalog:",
    "fast-csv": "5.0.2",
    "ffmpeg-static": "5.2.0",
    "ffprobe-static": "3.1.0",
    "fluent-ffmpeg": "2.1.3",
    "lexical": "0.20.0",
    "lodash": "4.17.21",
    "lucide-react": "0.446.0",
    "motion": "catalog:",
    "multer": "1.4.5-lts.1",
    "pg": "8.13.0",
    "react-colorful": "5.6.1",
    "react-dropzone": "14.2.9",
    "react-easy-crop": "5.4.1",
    "react-hook-form": "catalog:",
    "react-image-crop": "11.0.7",
    "resend": "4.1.2",
    "sharp": "0.33.5",
    "slugify": "1.6.6",
    "stripe": "catalog:",
    "svgo": "3.3.2",
    "uuid": "catalog:",
    "zod": "catalog:"
  },
  "devDependencies": {
    "@swc/core": "1.7.28",
    "@swc/jest": "0.2.36",
    "@tanstack/react-query": "catalog:",
    "@tanstack/react-query-devtools": "catalog:",
    "@types/color": "4.2.0",
    "@types/ffprobe-static": "2.0.3",
    "@types/fluent-ffmpeg": "2.1.27",
    "@types/jest": "29.5.12",
    "@types/lodash": "4.17.10",
    "@types/multer": "1.4.12",
    "@types/node": "catalog:",
    "@types/react": "catalog:",
    "@types/react-dom": "catalog:",
    "@types/uuid": "catalog:",
    "jest": "29.7.0",
    "react": "catalog:",
    "react-dom": "catalog:",
    "react-router-dom": "6.20.1",
    "ts-node": "10.9.2",
    "typescript": "catalog:",
    "vite": "5.4.14"
  }
}

Node.js version

v22

Database and its version

16

Operating system name and version

MacOS

Browser name

Arc

What happended?

In the case of a ⁠buyxgety promotion, the promotion is applied randomly to line items.

As illustrated below:

The promotion is applied to the first line, indicated by the presence of an adjustment.

When I increase the quantity, whether on the first line (with the promotion) or the second line, the promotion shifts to the second line.

Expected behavior

The adjustment should remain on the same line. For instance, if it’s a gift or a promotion and I have an adjustment, I would like to hide the quantity selector. This is because I don't want customers to be able to increase the quantity. Additionally, having the promo badge moving is weird.

Actual behavior

When the customer increases the quantity, the adjustment shifts to another line.

Link to reproduction repo

https://github.com/medusajs/medusa-starter-default