From 0eeccf1b3bfe829985eac9219b1f8fefb0e031c3 Mon Sep 17 00:00:00 2001
From: Oleksandr Fediashov <olfedias@microsoft.com>
Date: Tue, 17 Dec 2024 17:31:48 +0200
Subject: [PATCH] chore: fix N* tests (#33480)

---
 packages/fluentui/projects-test/assets/cra/src/index.tsx | 7 +++++++
 packages/fluentui/projects-test/src/createReactApp.ts    | 5 +++++
 packages/fluentui/react-northstar/jest.config.js         | 3 +++
 3 files changed, 15 insertions(+)
 create mode 100644 packages/fluentui/projects-test/assets/cra/src/index.tsx

diff --git a/packages/fluentui/projects-test/assets/cra/src/index.tsx b/packages/fluentui/projects-test/assets/cra/src/index.tsx
new file mode 100644
index 0000000000000..b0ddfeee00e36
--- /dev/null
+++ b/packages/fluentui/projects-test/assets/cra/src/index.tsx
@@ -0,0 +1,7 @@
+import * as React from 'react';
+import * as ReactDOM from 'react-dom';
+import App from './App';
+
+const root = document.getElementById('root') as HTMLElement;
+
+ReactDOM.render(<App />, root);
diff --git a/packages/fluentui/projects-test/src/createReactApp.ts b/packages/fluentui/projects-test/src/createReactApp.ts
index d8b81ba6e11ac..f926fe4b802f0 100644
--- a/packages/fluentui/projects-test/src/createReactApp.ts
+++ b/packages/fluentui/projects-test/src/createReactApp.ts
@@ -37,6 +37,11 @@ export async function createReactApp() {
   await addResolutionPathsForProjectPackages(testAppPathRoot);
 
   await shEcho(`yarn add ${packedPackages['@fluentui/react-northstar']}`, testAppPathRoot);
+
+  // Enforce React 17
+  const dependencies = ['@types/react@17', '@types/react-dom@17', 'react@17', 'react-dom@17'].join(' ');
+  await shEcho(`yarn add ${dependencies}`, tempPaths.testApp);
+
   logger(`✔️ Fluent UI packages were added to dependencies`);
 
   logger("STEP 3. Reference Fluent UI components in test project's App.tsx");
diff --git a/packages/fluentui/react-northstar/jest.config.js b/packages/fluentui/react-northstar/jest.config.js
index 5cdf12e0e8ac3..d873ab12d7231 100644
--- a/packages/fluentui/react-northstar/jest.config.js
+++ b/packages/fluentui/react-northstar/jest.config.js
@@ -10,6 +10,9 @@ const config = commonConfig({
     // Legacy aliases, they should not be used in new tests
     ...getAliases(),
   },
+  // Keeps Jest from using too much memory as GC gets invokes more often, makes tests slower
+  // https://stackoverflow.com/a/75857711
+  workerIdleMemoryLimit: '1024MB',
 });
 config.setupFilesAfterEnv = [...config.setupFilesAfterEnv, './jest-setup.js'];