test(UnifiedFontStore): add filter change reset tests

src/entities/Font/model/store/unifiedFontStore/unifiedFontStore.test.ts

@@ -1,4 +1,5 @@
 import { QueryClient } from '@tanstack/query-core';
+import { tick } from 'svelte';
 import {
     afterEach,
     beforeEach,
@@ -331,3 +332,41 @@ describe('filter setters', () => {
         expect(store.params.sort).toBe('popularity');
     });
 });
+
+describe('filter change resets pagination', () => {
+    let store: UnifiedFontStore;
+
+    beforeEach(async () => {
+        store = new UnifiedFontStore({ limit: 10 });
+        // Let the initial effect run so #previousFilterParams is set.
+        // Without this, the first filter change is treated as initialisation, not a reset.
+        await tick();
+    });
+
+    afterEach(() => {
+        store.destroy();
+        queryClient.clear();
+        vi.resetAllMocks();
+    });
+
+    it('resets offset to 0 when a filter changes', async () => {
+        store.setParams({ offset: 20 });
+
+        store.setSearch('roboto');
+        await tick();
+
+        expect(store.params.offset).toBe(0);
+    });
+
+    it('clears accumulated fonts when a filter changes', async () => {
+        const fonts = generateMockFonts(3);
+        mockedFetch.mockResolvedValue(makeResponse(fonts));
+        await store.refetch();
+        expect(store.fonts).toHaveLength(3);
+
+        store.setSearch('roboto');
+        await tick();
+
+        expect(store.fonts).toHaveLength(0);
+    });
+});