Testing a Reducer Exercise.md

Let's say we're building a packing list and it keeps track of items in the following manner:

type Item = {
  id: string;
  name: string;
  packed: boolean;
};

And, let's assume we have a reducer that supports the following state:

const items = [
  {
    id: 2,
    name: 'iPhone',
    packed: true,
  },
  {
    id: 2,
    name: 'iPhone charger',
    packed: false,
  },
];

This reducer supports the following actions:

• add({ name }): adds an item with a given name to the application's state.
• remove({ id }): removes the item with that id from the application's state.
• update({ id, name?, packed? }): updates whatever properties are on the provided item.
• toggle({ id }): Flips the packed boolean to its opposite.
• markAllAsUnpacked(): Sets the packed boolean on all items to false.

Your Mission

We have an example implementation in items-slice.ts.

Can you make the tests in items.slice.ts pass?

Solution

You can see a possible solution here.