add unit tests

tests/hooks/useSorting.test.tsx

@@ -0,0 +1,97 @@
+import { act } from 'react';
+import { describe, expect, it } from 'vitest';
+import { formatSortParam, useSorting } from '../../src/hooks/useSorting';
+import { renderHook } from '../helpers/renderHook';
+
+describe('useSorting', () => {
+    it('starts from default sort and cycles asc/desc/default', () => {
+        const { result } = renderHook(() => useSorting({ field: 'createdAt', direction: 'asc' }));
+
+        expect(result.current.activeSort).toEqual({ field: 'createdAt', direction: 'asc' });
+        expect(result.current.sortParam).toBe('createdAt');
+
+        act(() => {
+            result.current.toggleSort('name');
+        });
+        expect(result.current.activeSort).toEqual({ field: 'name', direction: 'asc' });
+        expect(result.current.sortParam).toBe('name');
+
+        act(() => {
+            result.current.toggleSort('name');
+        });
+        expect(result.current.activeSort).toEqual({ field: 'name', direction: 'desc' });
+        expect(result.current.sortParam).toBe('-name');
+
+        act(() => {
+            result.current.toggleSort('name');
+        });
+        expect(result.current.activeSort).toEqual({ field: 'createdAt', direction: 'asc' });
+        expect(result.current.sortParam).toBe('createdAt');
+    });
+
+    it('cycles sort state without a baseline default', () => {
+        const { result } = renderHook(() => useSorting(null));
+
+        expect(result.current.activeSort).toBeNull();
+        expect(result.current.sortParam).toBeUndefined();
+
+        act(() => {
+            result.current.toggleSort('updatedAt');
+        });
+        expect(result.current.sortParam).toBe('updatedAt');
+
+        act(() => {
+            result.current.toggleSort('updatedAt');
+        });
+        expect(result.current.sortParam).toBe('-updatedAt');
+
+        act(() => {
+            result.current.toggleSort('updatedAt');
+        });
+        expect(result.current.sortParam).toBeUndefined();
+    });
+
+    it('supports manual setSort and resetSort', () => {
+        const { result } = renderHook(() => useSorting({ field: 'createdAt', direction: 'desc' }));
+
+        expect(result.current.sortParam).toBe('-createdAt');
+
+        act(() => {
+            result.current.setSort({ field: 'title', direction: 'asc' });
+        });
+        expect(result.current.sortParam).toBe('title');
+
+        act(() => {
+            result.current.resetSort();
+        });
+        expect(result.current.sortParam).toBe('-createdAt');
+    });
+
+    it('toggles baseline field directly between baseline and opposite direction', () => {
+        const { result } = renderHook(() => useSorting({ field: 'createdAt', direction: 'desc' }));
+
+        expect(result.current.sortParam).toBe('-createdAt');
+
+        act(() => {
+            result.current.toggleSort('createdAt');
+        });
+        expect(result.current.sortParam).toBe('createdAt');
+
+        act(() => {
+            result.current.toggleSort('createdAt');
+        });
+        expect(result.current.sortParam).toBe('-createdAt');
+
+        act(() => {
+            result.current.toggleSort('createdAt');
+        });
+        expect(result.current.sortParam).toBe('createdAt');
+    });
+
+    it('formats sort params safely', () => {
+        expect(formatSortParam(null)).toBeUndefined();
+        expect(formatSortParam(undefined)).toBeUndefined();
+        expect(formatSortParam({ field: 'updatedAt', direction: 'desc' })).toBe('-updatedAt');
+        expect(formatSortParam({ field: 'updatedAt', direction: 'asc' })).toBe('updatedAt');
+    });
+});