fix(multi-caching): minor issues

Author: zzau13

src/multi-caching.ts

@@ -1,10 +1,7 @@
 import { Cache, Milliseconds } from './caching';
 
-export type MultiCache = Omit<Cache, 'store'> & {
-  mset(args: [string, unknown][], ttl?: Milliseconds): Promise<void>;
-  mget(...args: string[]): Promise<unknown[]>;
-  mdel(...args: string[]): Promise<void>;
-};
+export type MultiCache = Omit<Cache, 'store'> &
+  Pick<Cache['store'], 'mset' | 'mget' | 'mdel'>;
 
 /**
  * Module that lets you specify a hierarchy of caches.

test/multi-caching.test.ts

@@ -21,6 +21,19 @@ describe('multiCaching', () => {
   let defaultTtl: number;
   let key: string;
 
+  async function multiMset() {
+    const keys = [faker.datatype.string(20), faker.datatype.string(20)];
+    const values = [faker.datatype.string(), faker.datatype.string()];
+    await multiCache.mset(
+      [
+        [keys[0], values[0]],
+        [keys[1], values[1]],
+      ],
+      defaultTtl,
+    );
+    return { keys, values };
+  }
+
   beforeEach(async () => {
     ttl = 100;
     defaultTtl = 5000;
@@ -93,15 +106,7 @@ describe('multiCaching', () => {
 
     describe('mset()', () => {
       it('lets us set multiple keys in all caches', async () => {
-        const keys = [faker.datatype.string(20), faker.datatype.string(20)];
-        const values = [faker.datatype.string(), faker.datatype.string()];
-        await multiCache.mset(
-          [
-            [keys[0], values[0]],
-            [keys[1], values[1]],
-          ],
-          defaultTtl,
-        );
+        const { keys, values } = await multiMset();
         await expect(memoryCache.get(keys[0])).resolves.toEqual(values[0]);
         await expect(memoryCache2.get(keys[0])).resolves.toEqual(values[0]);
         await expect(memoryCache3.get(keys[0])).resolves.toEqual(values[0]);
@@ -113,31 +118,28 @@ describe('multiCaching', () => {
 
     describe('mget()', () => {
       it('lets us get multiple keys', async () => {
-        const keys = [faker.datatype.string(20), faker.datatype.string(20)];
-        const values = [faker.datatype.string(), faker.datatype.string()];
+        const { keys, values } = await multiMset();
         await multiCache.set(keys[0], values[0], defaultTtl);
         await memoryCache3.set(keys[1], values[1], defaultTtl);
         await expect(multiCache.mget(...keys)).resolves.toStrictEqual(values);
       });
+
+      it('lets us get multiple undefined', async () => {
+        const len = 4;
+        await multiMset();
+        const args = faker.datatype.array(len).map((x) => '' + x);
+        await expect(multiCache.mget(...args)).resolves.toStrictEqual(
+          new Array(len).fill(undefined),
+        );
+      });
     });
 
     describe('mdel()', () => {
       it('lets us delete multiple keys', async () => {
-        const keys = [faker.datatype.string(20), faker.datatype.string(20)];
-        const values = [faker.datatype.string(), faker.datatype.string()];
-        await multiCache.mset(
-          [
-            [keys[0], values[0]],
-            [keys[1], values[1]],
-          ],
-          defaultTtl,
-        );
-        await expect(multiCache.mget(...keys)).resolves.toStrictEqual(values);
+        const { keys } = await multiMset();
         await multiCache.mdel(...keys);
-        await expect(multiCache.mget(...keys)).resolves.toStrictEqual([
-          undefined,
-          undefined,
-        ]);
+        await expect(memoryCache.get(keys[0])).resolves.toBeUndefined();
+        await expect(memoryCache.get(keys[1])).resolves.toBeUndefined();
       });
     });