[Bug]: Inventory system fails with shared inventory items

[Midunas]

Package.json file

{
    "name": "medusa-starter-default",
    "version": "0.0.1",
    "description": "A starter for Medusa projects.",
    "author": "Medusa (https://medusajs.com)",
    "license": "MIT",
    "keywords": [
      "sqlite",
      "postgres",
      "typescript",
      "ecommerce",
      "headless",
      "medusa"
    ],
    "scripts": {
      "build": "medusa build",
      "seed": "medusa exec ./src/scripts/seed.ts",
      "start": "medusa start",
      "dev": "medusa develop",
      "migrate": "medusa db:migrate"
    },
    "dependencies": {
      "@medusajs/admin-sdk": "2.2.0",
      "@medusajs/cli": "2.2.0",
      "@medusajs/framework": "2.2.0",
      "@medusajs/link-modules": "^2.2.0",
      "@medusajs/medusa": "2.2.0",
      "@mikro-orm/core": "5.9.7",
      "@mikro-orm/knex": "5.9.7",
      "@mikro-orm/migrations": "5.9.7",
      "@mikro-orm/postgresql": "5.9.7",
      "awilix": "^8.0.1",
      "pg": "^8.13.0"
    },
    "devDependencies": {
      "@medusajs/test-utils": "2.2.0",
      "@mikro-orm/cli": "5.9.7",
      "@swc/core": "1.5.7",
      "@swc/jest": "^0.2.36",
      "@types/jest": "^29.5.13",
      "@types/node": "^20.0.0",
      "@types/react": "^18.3.2",
      "@types/react-dom": "^18.2.25",
      "jest": "^29.7.0",
      "prop-types": "^15.8.1",
      "react": "^18.2.0",
      "react-dom": "^18.2.0",
      "ts-node": "^10.9.2",
      "typescript": "^5.6.2",
      "vite": "^5.2.11"
    },
    "engines": {
      "node": ">=20"
    },
    "packageManager": "[email protected]+sha512.5383cc12567a95f1d668fbe762dfe0075c595b4bfff433be478dbbe24e05251a8e8c3eb992a986667c1d53b6c3a9c85b8398c35a960587fbd9fa3a0915406728"
  }

Node.js version

v23.5.0

Database and its version

PostgreSQL 17.2

Operating system name and version

macOS 15.2

Browser name

Google Chrome

What happended?

Getting error: "Variant variant_XXXXXXX does not have any inventory items associated with it" when placing order with 2 variants of the same product. Despite the product variants being linked to the same inventory item.

Setup

• Multiple variants (1 bottle, 2 bottles, 3 bottles packs)
• All variants linked to same inventory item (since they're the same physical product)
• Trying to place order with different variants in cart.

Expected behavior

• Should allow adding multiple variants that share the same inventory item
• Should allow ordering multiple variants that share the same inventory item
• Should expose inventory_item data to fulfillment module to allow correct shipping information with quantity

Actual behavior

Getting mentioned error.
Cart becomes unusable with error: "Cart cart_XXXXX is already completed"
System doesn't handle multiple variants sharing the same inventory item pool

Any suggestions how to move forward with my case are welcome!

Thank you.

[joekendal]

I thought variant should be 1-to-1 with inventory item. You are doing many-to-1 why?

[joekendal]

Does this help? https://docs.medusajs.com/resources/commerce-modules/inventory/inventory-kit