fix: cache eviction bug

frontend/src/hooks/api/getters/useFeatureSearch/useFeatureSearch.test.tsx

@@ -2,7 +2,10 @@ import type { FC } from 'react';
 import { render, screen } from '@testing-library/react';
 import '@testing-library/jest-dom';
 import { testServerRoute, testServerSetup } from 'utils/testServer';
-import { useFeatureSearch } from './useFeatureSearch.ts';
+import {
+    getFeatureSearchFetcher,
+    useFeatureSearch,
+} from './useFeatureSearch.ts';
 import { useSWRConfig } from 'swr';
 
 const server = testServerSetup();
@@ -93,4 +96,18 @@ describe('useFeatureSearch', () => {
         rerender(<TestComponent params={{ project }} />);
         await screen.findByText(/Total: 0/);
     });
+
+    test('should give the same cache key, regardless of parameter order', async () => {
+        const params1 = {
+            query: 'query-string',
+            project: 'IS:project',
+        };
+        const params2 = {
+            project: 'IS:project',
+            query: 'query-string',
+        };
+        const { KEY: key1 } = getFeatureSearchFetcher(params1);
+        const { KEY: key2 } = getFeatureSearchFetcher(params2);
+        expect(key1).toEqual(key2);
+    });
 });

frontend/src/hooks/api/getters/useFeatureSearch/useFeatureSearch.ts

@@ -100,12 +100,13 @@ const createFeatureSearch = () => {
 
 export const DEFAULT_PAGE_LIMIT = 25;
 
-const getFeatureSearchFetcher = (params: SearchFeaturesParams) => {
+export const getFeatureSearchFetcher = (params: SearchFeaturesParams) => {
     const urlSearchParams = new URLSearchParams(
         Array.from(
             Object.entries(params)
                 .filter(([_, value]) => !!value)
-                .map(([key, value]) => [key, value.toString()]), // TODO: parsing non-string parameters
+                .map(([key, value]) => [key, value.toString()]) // TODO: parsing non-string parameters
+                .toSorted(),
         ),
     ).toString();
     const KEY = `${PATH}${urlSearchParams}`;

frontend/src/hooks/useClearSWRCache.test.ts

@@ -14,7 +14,7 @@ describe('manageCacheEntries', () => {
         expect(cacheMock.has('prefix-3')).toBe(true);
     });
 
-    it('should keep the SWR_CACHE_SIZE entries and delete the rest', () => {
+    it('should keep the SWR_CACHE_SIZE entries and delete the rest, keeping the most recent entries', () => {
         const cacheMock = new Map();
         cacheMock.set('prefix-1', {});
         cacheMock.set('prefix-2', {});
@@ -23,8 +23,19 @@ describe('manageCacheEntries', () => {
 
         clearCacheEntries(cacheMock, 'prefix-4', 'prefix-', 2);
 
-        expect(cacheMock.has('prefix-4')).toBe(true);
-        expect([...cacheMock.keys()].length).toBe(2);
+        expect([...cacheMock.keys()]).toStrictEqual(['prefix-3', 'prefix-4']);
+    });
+
+    it('should not delete the current key, even if it would be cleared as part of the cache size limit', () => {
+        const cacheMock = new Map();
+        cacheMock.set('prefix-1', {});
+        cacheMock.set('prefix-2', {});
+        cacheMock.set('prefix-3', {});
+        cacheMock.set('prefix-4', {});
+
+        clearCacheEntries(cacheMock, 'prefix-2', 'prefix-', 2);
+
+        expect([...cacheMock.keys()]).toStrictEqual(['prefix-2', 'prefix-4']);
     });
 
     it('should handle case when SWR_CACHE_SIZE is larger than number of entries', () => {
@@ -50,4 +61,16 @@ describe('manageCacheEntries', () => {
         expect(cacheMock.has('other-2')).toBe(true);
         expect(cacheMock.has('prefix-3')).toBe(true);
     });
+
+    it('treats a negative cache size as zero', () => {
+        const cacheMock = new Map();
+        cacheMock.set('prefix-1', {});
+        cacheMock.set('prefix-2', {});
+        cacheMock.set('prefix-3', {});
+        cacheMock.set('prefix-4', {});
+
+        clearCacheEntries(cacheMock, 'prefix-3', 'prefix-', -1);
+
+        expect([...cacheMock.keys()]).toStrictEqual(['prefix-3']);
+    });
 });

frontend/src/hooks/useClearSWRCache.ts

@@ -13,7 +13,12 @@ export const clearCacheEntries = (
     const filteredKeys = keys.filter(
         (key) => key.startsWith(clearPrefix) && key !== currentKey,
     );
-    const keysToDelete = filteredKeys.slice(SWR_CACHE_SIZE - 1);
+
+    const entriesToLeave = SWR_CACHE_SIZE - 1;
+    const keysToDelete =
+        entriesToLeave <= 0
+            ? filteredKeys
+            : filteredKeys.slice(0, -entriesToLeave);
 
     keysToDelete.forEach((key) => cache.delete(key));
 };