From efe5a9c475ad4c250f0969bea08f38ecad679416 Mon Sep 17 00:00:00 2001
From: Brian Vaughn <bvaughn@fb.com>
Date: Thu, 1 Oct 2020 10:09:23 -0400
Subject: [PATCH] Added DebugTracing tests for CPU bound suspense

---
 .../__tests__/DebugTracing-test.internal.js   | 85 +++++++++++++++++++
 1 file changed, 85 insertions(+)

diff --git a/packages/react-reconciler/src/__tests__/DebugTracing-test.internal.js b/packages/react-reconciler/src/__tests__/DebugTracing-test.internal.js
index 9ee4271dfbca8..2df04c8c88544 100644
--- a/packages/react-reconciler/src/__tests__/DebugTracing-test.internal.js
+++ b/packages/react-reconciler/src/__tests__/DebugTracing-test.internal.js
@@ -96,6 +96,45 @@ describe('DebugTracing', () => {
     expect(logs).toEqual(['log: ⚛️ Example resolved']);
   });
 
+  // @gate experimental && build === 'development' && enableDebugTracing
+  it('should log sync render with CPU suspense', () => {
+    function Example() {
+      console.log('<Example/>');
+      return null;
+    }
+
+    function Wrapper({children}) {
+      console.log('<Wrapper/>');
+      return children;
+    }
+
+    ReactTestRenderer.create(
+      <React.unstable_DebugTracingMode>
+        <Wrapper>
+          <React.Suspense fallback={null} unstable_expectedLoadTime={1}>
+            <Example />
+          </React.Suspense>
+        </Wrapper>
+      </React.unstable_DebugTracingMode>,
+    );
+
+    expect(logs).toEqual([
+      'group: ⚛️ render (0b0000000000000000000000000000001)',
+      'log: <Wrapper/>',
+      'groupEnd: ⚛️ render (0b0000000000000000000000000000001)',
+    ]);
+
+    logs.splice(0);
+
+    expect(Scheduler).toFlushUntilNextPaint([]);
+
+    expect(logs).toEqual([
+      'group: ⚛️ render (0b0000010000000000000000000000000)',
+      'log: <Example/>',
+      'groupEnd: ⚛️ render (0b0000010000000000000000000000000)',
+    ]);
+  });
+
   // @gate experimental && build === 'development' && enableDebugTracing
   it('should log concurrent render with suspense', async () => {
     const fakeSuspensePromise = Promise.resolve(true);
@@ -130,6 +169,52 @@ describe('DebugTracing', () => {
     expect(logs).toEqual(['log: ⚛️ Example resolved']);
   });
 
+  // @gate experimental && build === 'development' && enableDebugTracing
+  it('should log concurrent render with CPU suspense', () => {
+    function Example() {
+      console.log('<Example/>');
+      return null;
+    }
+
+    function Wrapper({children}) {
+      console.log('<Wrapper/>');
+      return children;
+    }
+
+    ReactTestRenderer.create(
+      <React.unstable_DebugTracingMode>
+        <Wrapper>
+          <React.Suspense fallback={null} unstable_expectedLoadTime={1}>
+            <Example />
+          </React.Suspense>
+        </Wrapper>
+      </React.unstable_DebugTracingMode>,
+      {unstable_isConcurrent: true},
+    );
+
+    expect(logs).toEqual([]);
+
+    logs.splice(0);
+
+    expect(Scheduler).toFlushUntilNextPaint([]);
+
+    expect(logs).toEqual([
+      'group: ⚛️ render (0b0000000000000000000001000000000)',
+      'log: <Wrapper/>',
+      'groupEnd: ⚛️ render (0b0000000000000000000001000000000)',
+    ]);
+
+    logs.splice(0);
+
+    expect(Scheduler).toFlushUntilNextPaint([]);
+
+    expect(logs).toEqual([
+      'group: ⚛️ render (0b0000010000000000000000000000000)',
+      'log: <Example/>',
+      'groupEnd: ⚛️ render (0b0000010000000000000000000000000)',
+    ]);
+  });
+
   // @gate experimental && build === 'development' && enableDebugTracing
   it('should log cascading class component updates', () => {
     class Example extends React.Component {