@jetta/item-amount-controller

JavaScript library that groups item quantities by id and decrements them during allocation.

Requirements

• Node.js 24+
• npm

How to install

npm ci
npm run build

Consumers install the published package:

npm install @jetta/item-amount-controller

Usage

import { Item_Amount_Controller } from '@jetta/item-amount-controller'

const controller = new Item_Amount_Controller([
    { _id: 'box', get_amount: () => 2, get_id: () => 'box' }
])

controller.discount_single_item({ _id: 'box' })

CommonJS:

const { Item_Amount_Controller } = require('@jetta/item-amount-controller')

The default key is item._id when it is present, otherwise item.get_id(). Pass a second constructor argument to group by another key. copy() clones the amount map and then uses the default key.

Dependencies

No runtime dependencies.

Scripts

| Command | Description | |---------|-------------| | npm test | Mocha tests | | npm run lint | ESLint | | npm run build | Emit ESM and CommonJS to build/ and check both entries | | npm run coverage | Tests with 80% coverage gate (local) | | npm run coverage:ci | Tests with 75% coverage gate (CI) | | npm run lint:package | publint strict check |

Layout

• src/index.js — public exports
• src/Item_Amount_Controller.js — amount ledger
• src/exceptions/ — unknown id and insufficient amount
• test/src/ — mirrors src/