diff --git a/packages/toolkit/src/test/srcShared/fs.test.ts b/packages/toolkit/src/test/srcShared/fs.test.ts
index c15ba79165f..7d3a6ccefdc 100644
--- a/packages/toolkit/src/test/srcShared/fs.test.ts
+++ b/packages/toolkit/src/test/srcShared/fs.test.ts
@@ -13,6 +13,7 @@ import * as os from 'os'
 import { isMinimumVersion } from '../../shared/vscode/env'
 import Sinon from 'sinon'
 import * as extensionUtilities from '../../shared/extensionUtilities'
+import crypto from 'crypto'
 
 function isWin() {
     return os.platform() === 'win32'
@@ -174,7 +175,7 @@ describe('FileSystem', function () {
                 await fsCommon.mkdir(dirPath)
 
                 assert.ok(existsSync(dirPath))
-                assert.ok(mkdirSpy.calledOnce)
+                assert.strictEqual(mkdirSpy.callCount, 1)
             })
         })
     })
@@ -299,8 +300,11 @@ describe('FileSystem', function () {
         return path.join(testRootPath(), relativePath)
     }
 
+    let _testRootPath: string | undefined
+
     function testRootPath() {
-        return path.join(fakeContext.globalStorageUri.fsPath, 'testDir')
+        _testRootPath ??= path.join(fakeContext.globalStorageUri.fsPath, crypto.randomBytes(4).toString('hex'))
+        return _testRootPath
     }
 
     async function makeTestRoot() {
@@ -308,6 +312,7 @@ describe('FileSystem', function () {
     }
 
     async function deleteTestRoot() {
-        return rmSync(testRootPath(), { recursive: true })
+        rmSync(testRootPath(), { recursive: true })
+        _testRootPath = undefined
     }
 })