AI Code Toolkit

import { describe, expect, it } from 'vitest'; import { PaginationHelper } from '../../src/utils/pagination'; describe('PaginationHelper', () => { describe('encodeCursor / decodeCursor', () => { it('should encode and decode cursor correctly', () => { const index = 20; const cursor = PaginationHelper.encodeCursor(index); expect(cursor).toBe('20'); const decoded = PaginationHelper.decodeCursor(cursor); expect(decoded).toBe(20); }); it('should return 0 for invalid cursor', () => { expect(PaginationHelper.decodeCursor('invalid-cursor')).toBe(0); expect(PaginationHelper.decodeCursor('')).toBe(0); }); it('should return 0 for undefined cursor', () => { expect(PaginationHelper.decodeCursor(undefined)).toBe(0); }); it('should return 0 for negative cursor', () => { expect(PaginationHelper.decodeCursor('-1')).toBe(0); expect(PaginationHelper.decodeCursor('-10')).toBe(0); }); it('should handle zero cursor', () => { const cursor = PaginationHelper.encodeCursor(0); expect(cursor).toBe('0'); expect(PaginationHelper.decodeCursor('0')).toBe(0); }); }); describe('paginate', () => { const items = Array.from({ length: 25 }, (_, i) => ({ id: i + 1, name: `Item ${i + 1}` })); it('should return first page with no cursor', () => { const result = PaginationHelper.paginate(items); expect(result.items).toHaveLength(10); expect(result.items[0]).toEqual({ id: 1, name: 'Item 1' }); expect(result.items[9]).toEqual({ id: 10, name: 'Item 10' }); expect(result.nextCursor).toBe('10'); // Next cursor points to index 10 expect(result._meta).toEqual({ total: 25, offset: 0, limit: 10 }); }); it('should return second page with cursor', () => { const result = PaginationHelper.paginate(items, '10'); expect(result.items).toHaveLength(10); expect(result.items[0]).toEqual({ id: 11, name: 'Item 11' }); expect(result.items[9]).toEqual({ id: 20, name: 'Item 20' }); expect(result.nextCursor).toBe('20'); // Next cursor points to index 20 expect(result._meta).toEqual({ total: 25, offset: 10, limit: 10 }); }); it('should return last page without nextCursor', () => { const result = PaginationHelper.paginate(items, '20'); expect(result.items).toHaveLength(5); expect(result.items[0]).toEqual({ id: 21, name: 'Item 21' }); expect(result.items[4]).toEqual({ id: 25, name: 'Item 25' }); expect(result.nextCursor).toBeUndefined(); expect(result._meta).toEqual({ total: 25, offset: 20, limit: 10 }); }); it('should handle custom page size', () => { const result = PaginationHelper.paginate(items, undefined, 5); expect(result.items).toHaveLength(5); expect(result.items[0]).toEqual({ id: 1, name: 'Item 1' }); expect(result.items[4]).toEqual({ id: 5, name: 'Item 5' }); expect(result.nextCursor).toBe('5'); expect(result._meta).toEqual({ total: 25, offset: 0, limit: 5 }); }); it('should handle empty array', () => { const result = PaginationHelper.paginate([]); expect(result.items).toHaveLength(0); expect(result.nextCursor).toBeUndefined(); expect(result._meta).toEqual({ total: 0, offset: 0, limit: 10 }); }); it('should handle array smaller than page size', () => { const smallItems = [ { id: 1, name: 'Item 1' }, { id: 2, name: 'Item 2' }, ]; const result = PaginationHelper.paginate(smallItems); expect(result.items).toHaveLength(2); expect(result.nextCursor).toBeUndefined(); expect(result._meta).toEqual({ total: 2, offset: 0, limit: 10 }); }); it('should handle exact page size multiples', () => { const exactItems = Array.from({ length: 20 }, (_, i) => ({ id: i + 1, name: `Item ${i + 1}`, })); // First page const page1 = PaginationHelper.paginate(exactItems); expect(page1.items).toHaveLength(10); expect(page1.nextCursor).toBe('10'); // Second page (last page) const page2 = PaginationHelper.paginate(exactItems, page1.nextCursor); expect(page2.items).toHaveLength(10); expect(page2.nextCursor).toBeUndefined(); }); it('should handle invalid cursor by treating as first page', () => { const result = PaginationHelper.paginate(items, 'invalid-cursor'); expect(result.items).toHaveLength(10); expect(result.items[0]).toEqual({ id: 1, name: 'Item 1' }); expect(result._meta).toEqual({ total: 25, offset: 0, limit: 10 }); }); it('should support disabling metadata', () => { const result = PaginationHelper.paginate(items, undefined, 10, false); expect(result.items).toHaveLength(10); expect(result.nextCursor).toBe('10'); expect(result._meta).toBeUndefined(); }); }); describe('DEFAULT_PAGE_SIZE', () => { it('should have correct default page size', () => { expect(PaginationHelper.DEFAULT_PAGE_SIZE).toBe(10); }); }); });