Add tests for pagination

__tests__/carousel.spec.tsx

@@ -5,6 +5,7 @@ import { defaultProps } from '../src/components/carousel/defaultProps';
 import { carouselItemNodes, dynamicCarouselItemNodes } from './__fixtures__/nodes';
 import * as helpers from '../src/helpers';
 import { SlideDirection } from '../src/types/carousel';
+import * as hooks from '../src/hooks';
 
 describe('<Carousel />', () => {
 	let mockGetPageX: jest.SpyInstance<
@@ -303,51 +304,30 @@ describe('<Carousel />', () => {
 		expect(button!.innerHTML).toEqual('1');
 	});
 
-	it('should invoke beforeChange when beforeChange prop is defined on slide', async () => {
+	it('should slide to right when click right button', async () => {
-		const onBeforeChange = (_: SlideDirection) => {
+		const paginationCallback = jest.fn();
-			return;
+		const mockUsePrevious = jest
-		};
+			.spyOn(hooks, 'usePrevious')
-		const stub = jest.fn(onBeforeChange);
+			.mockImplementation(() => carouselItemNodes(2));
-		const { getByTestId } = render(
-			<Carousel
-				{...defaultProps}
-				infinite={true}
-				children={carouselItemNodes(4)}
-				beforeChange={stub}
-			/>,
-		);
-		const carousel = getByTestId('carousel');
-		const button = carousel.querySelector('button');
-
-		expect(button).not.toBeNull();
-
-		fireEvent.click(button!);
-		jest.runAllTimers();
-
-		expect(stub).toHaveBeenCalledTimes(1);
-	});
 
-	it('should invoke afterChange when afterChange prop is defined on slide', async () => {
-		const onAfterChange = (_: SlideDirection) => {
-			return;
-		};
-		const stub = jest.fn(onAfterChange);
 		const { getByTestId } = render(
 			<Carousel
 				{...defaultProps}
 				infinite={true}
 				children={carouselItemNodes(4)}
-				afterChange={stub}
+				pageCount={2}
+				paginationCallback={paginationCallback}
 			/>,
 		);
 		const carousel = getByTestId('carousel');
-		const button = carousel.querySelector('button');
+		const button = carousel.querySelectorAll('button')[1];
 
 		expect(button).not.toBeNull();
 
 		fireEvent.click(button!);
 		jest.runAllTimers();
 
-		expect(stub).toHaveBeenCalledTimes(1);
+		expect(paginationCallback).toHaveBeenCalledTimes(1);
+		expect(mockUsePrevious).toBeCalled();
 	});
 });

__tests__/helpers.spec.tsx

@@ -82,10 +82,17 @@ describe('helpers', () => {
 		const oldNodes = reactNodes('old', 5) as Item[];
 		const newNodes = reactNodes('new', 6) as Item[];
 		const expected = reactNodes('new', 5) as Item[];
+		const prevChildren = undefined;
 		const infinite = true;
 		const slide = 5;
 
-		const result = helpers.updateNodes(oldNodes, newNodes, slide, infinite);
+		const result = helpers.updateNodes(
+			oldNodes,
+			newNodes,
+			prevChildren,
+			slide,
+			infinite,
+		);
 
 		expect(result).toEqual(expected);
 	});
@@ -94,6 +101,7 @@ describe('helpers', () => {
 		const oldNodes = reactNodes('old', 5) as Item[];
 		const infinite = true;
 		const slide = 2;
+		const prevChildren = undefined;
 		const newNodes = ([
 			{
 				key: 14,
@@ -123,8 +131,44 @@ describe('helpers', () => {
 			},
 		] as unknown) as Item[];
 
-		const result = helpers.updateNodes(oldNodes, newNodes, slide, infinite);
+		const result = helpers.updateNodes(
+			oldNodes,
+			newNodes,
+			prevChildren,
+			slide,
+			infinite,
+		);
 
 		expect(result).toEqual(expectedNodes);
 	});
+
+	it('should update nodes when previous children length is less than new children', async () => {
+		const oldNodes = reactNodes('old', 5) as Item[];
+		const newNodes = reactNodes('new', 6) as Item[];
+		const prevChildren = newNodes.slice(0, 5);
+		const expected = newNodes.slice(1, 6).concat(newNodes);
+		const infinite = true;
+		const slide = 5;
+
+		const result = helpers.updateNodes(
+			oldNodes,
+			newNodes,
+			prevChildren,
+			slide,
+			infinite,
+		);
+
+		expect(result).toEqual(expected);
+	});
+
+	it('should get corre transform amount', async () => {
+		const width = 100;
+		const slideCount = 2;
+		const direction = SlideDirection.Left;
+		const expected = 200;
+
+		const result = helpers.getTransformAmount(width, slideCount, direction);
+
+		expect(result).toEqual(expected);
+	});
 });