Inventory Diff
A shop counts its stock twice a day. Each count is an object mapping item names to quantities. Write diffInventory(before, after) that returns:
added: items that only exist inafterremoved: items that only exist inbeforechanged: items in both whose quantity changed, as{ item, from, to }
Sort added and removed alphabetically, and sort changed by item name.
Examples
diffInventory({ apples: 5, pears: 2, plums: 7 }, { apples: 3, plums: 7, kiwis: 4 })
→ { added: ["kiwis"], removed: ["pears"], changed: [{ item: "apples", from: 5, to: 3 }] }
diffInventory({ tea: 1 }, { tea: 1 })
→ { added: [], removed: [], changed: [] }
project.js
JAVASCRIPT
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Tests
0 of 3 passing- •a busy morningdiffInventory({ apples: 5, pears: 2, plums: 7 }, { apples: 3, plums: 7, kiwis: 4 })expected { added: ["kiwis"], removed: ["pears"], changed: [{ item: "apples", from: 5, to: 3 }] }
- •nothing changeddiffInventory({ tea: 1 }, { tea: 1 })expected { added: [], removed: [], changed: [] }
- •sorted outputdiffInventory({ zinc: 1, iron: 2 }, { zinc: 4, iron: 1, gold: 1, copper: 3 })expected { added: ["copper", "gold"], removed: [], changed: [{ item: "iron", from: 2, to: 1 }, { item: "zinc", from: 1, to: 4 }] }
On the line
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Pass all 3 tests to claim it.