adding tests for carousel item behavior

Author: mituron

packages/accessibility/src/behaviors/Carousel/carouselItemBehavior.ts

@@ -2,10 +2,12 @@ import { Accessibility } from '../../types'
 import * as keyboardKey from 'keyboard-key'
 
 /**
+ * @description
+ * Adds attribute 'tabIndex=0' to 'root' slot if 'active' property and 'navigation' property is true. Sets the attribute to '-1' otherwise.
+ *
  * @specification
  * Adds attribute 'role=tabpanel' to 'root' slot if 'navigation' property is true. Sets the attribute to 'group' otherwise.
  * Adds attribute 'aria-hidden=false' to 'root' slot if 'active' property is true. Sets the attribute to 'true' otherwise.
- * Adds attribute 'tabIndex=0' to 'root' slot if 'active' property is true. Sets the attribute to '-1' otherwise.
  */
 const carouselItemBehavior: Accessibility<CarouselItemProps> = props => ({
   attributes: {

packages/accessibility/test/behaviors/caroseltemBehavior-test.tsx

@@ -0,0 +1,23 @@
+import { carouselItemBehavior } from '@fluentui/accessibility'
+
+describe('carouselItemBehavior.ts', () => {
+  test('set tabIndex="0" when carousel has navigation and item is visible ', () => {
+    const expectedResult = carouselItemBehavior({ navigation: true, active: true })
+    expect(expectedResult.attributes.root.tabIndex).toEqual(0)
+  })
+
+  test('set tabIndex="-1" when carousel has navigation and item is NOT visible ', () => {
+    const expectedResult = carouselItemBehavior({ navigation: true, active: false })
+    expect(expectedResult.attributes.root.tabIndex).toEqual(-1)
+  })
+
+  test('set tabIndex="-1" when carousel has NO navigation and item is visible', () => {
+    const expectedResult = carouselItemBehavior({ navigation: false, active: true })
+    expect(expectedResult.attributes.root.tabIndex).toEqual(-1)
+  })
+
+  test('set tabIndex="-1" when carousel has NO navigation and item is NOT visible', () => {
+    const expectedResult = carouselItemBehavior({ navigation: false, active: false })
+    expect(expectedResult.attributes.root.tabIndex).toEqual(-1)
+  })
+})