From d06e979d544d858e0c4a64cf38ff4c591b6917f0 Mon Sep 17 00:00:00 2001
From: Daniel Bankhead <danielbankhead@google.com>
Date: Wed, 11 Oct 2023 11:52:00 -0700
Subject: [PATCH 1/2] test: Use Sinon Fake Timer to Avoid Flaky Time Issue

---
 test/test.util.ts | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/test/test.util.ts b/test/test.util.ts
index 6871c621..e92babf5 100644
--- a/test/test.util.ts
+++ b/test/test.util.ts
@@ -13,10 +13,21 @@
 // limitations under the License.
 
 import {strict as assert} from 'assert';
+import * as sinon from 'sinon';
 
 import {LRUCache} from '../src/util';
 
 describe('util', () => {
+  let sandbox: sinon.SinonSandbox;
+
+  beforeEach(() => {
+    sandbox = sinon.createSandbox();
+  });
+
+  afterEach(() => {
+    sandbox.restore();
+  });
+
   describe('LRUCache', () => {
     it('should set and get a cached item', () => {
       const expected = 'value';
@@ -50,17 +61,22 @@ describe('util', () => {
     it('should evict items older than a supplied `maxAge`', async () => {
       const maxAge = 50;
 
+      sandbox.clock = sinon.useFakeTimers();
+
       const lru = new LRUCache({capacity: 5, maxAge});
 
       lru.set('first', 1);
       lru.set('second', 2);
 
-      await new Promise(res => setTimeout(res, maxAge + 1));
-
-      lru.set('third', 3);
+      // back to the future 🏎️
+      sandbox.clock.tick(maxAge + 1);
 
+      // these are too old
       assert.equal(lru.get('first'), undefined);
       assert.equal(lru.get('second'), undefined);
+
+      // just set, so should be fine
+      lru.set('third', 3);
       assert.equal(lru.get('third'), 3);
     });
   });

From 8c13c3b281b32b944759b78e7c42e27c49e86bc6 Mon Sep 17 00:00:00 2001
From: Daniel Bankhead <danielbankhead@google.com>
Date: Wed, 11 Oct 2023 12:01:44 -0700
Subject: [PATCH 2/2] chore: change order for clarity

---
 test/test.util.ts | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/test.util.ts b/test/test.util.ts
index e92babf5..6f584c9c 100644
--- a/test/test.util.ts
+++ b/test/test.util.ts
@@ -71,13 +71,13 @@ describe('util', () => {
       // back to the future 🏎️
       sandbox.clock.tick(maxAge + 1);
 
-      // these are too old
-      assert.equal(lru.get('first'), undefined);
-      assert.equal(lru.get('second'), undefined);
-
       // just set, so should be fine
       lru.set('third', 3);
       assert.equal(lru.get('third'), 3);
+
+      // these are too old
+      assert.equal(lru.get('first'), undefined);
+      assert.equal(lru.get('second'), undefined);
     });
   });
 });