✅ Add test and snapshot for ItemDisplayInput.

src/__tests__/components/ItemDisplayInput.test.js

@@ -0,0 +1,40 @@
+import { customRender } from '../../test-utils'
+import { fireEvent } from '@testing-library/react'
+import ItemDisplayInput from '../../components/ItemDisplayInput'
+
+const item = {
+  name: 'Test Item',
+  space: 1,
+  value: 1,
+  id: '0',
+  destination: {
+    name: 'Test Planet 2',
+    value: 50
+  },
+  quantity: 10
+}
+
+describe('<ItemDisplayInput />', () => {
+  it('Should render the <ItemDisplayInput /> component.', () => {
+    const container = customRender({
+      component: ItemDisplayInput,
+      props: { item }
+    })
+    expect(container.asFragment()).toMatchSnapshot()
+  })
+
+  it('Should handle the user buying an item.', () => {
+    const container = customRender({
+      component: ItemDisplayInput,
+      props: { item }
+    })
+
+    const { getByTestId } = container
+
+    const quantityInput = container.container.querySelector('#quantity-input-0')
+    const addButton = getByTestId('add-button-0')
+
+    fireEvent.change(quantityInput, { target: { value: 2 } })
+    fireEvent.click(addButton)
+  })
+})

src/__tests__/components/__snapshots__/ItemDisplayInput.test.js.snap

@@ -0,0 +1,47 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`<ItemDisplayInput /> Should render the <ItemDisplayInput /> component. 1`] = `
+<DocumentFragment>
+  <div
+    class="StyledBox-sc-13pk1d4-0 hroMnY"
+  >
+    <button
+      class="StyledButton-sc-323bzc-0 jJyttA"
+      data-testid="add-button-0"
+      disabled=""
+      type="button"
+    >
+      <svg
+        aria-label="Add"
+        class="StyledIcon-ofa7kd-0 iOkQrb"
+        viewBox="0 0 24 24"
+      >
+        <path
+          d="M12,22 L12,2 M2,12 L22,12"
+          fill="none"
+          stroke="#000"
+          stroke-width="2"
+        />
+      </svg>
+    </button>
+    <div
+      class="StyledBox__StyledBoxGap-sc-13pk1d4-1 hPsznL"
+    />
+    <label
+      for="quantity-input-0"
+    >
+      Quantity to Add
+    </label>
+    <div
+      class="StyledBox__StyledBoxGap-sc-13pk1d4-1 hPsznL"
+    />
+    <input
+      id="quantity-input-0"
+      max="5"
+      min="0"
+      type="number"
+      value="0"
+    />
+  </div>
+</DocumentFragment>
+`;