From 768c171f133e0a901722333237ca26e574c03465 Mon Sep 17 00:00:00 2001
From: Conrad Buck <conartist6@gmail.com>
Date: Thu, 4 Feb 2021 15:29:58 -0500
Subject: [PATCH] Ensure verbose mode prints output synchronously

Fixes #8208
---
 packages/jest-reporters/src/DefaultReporter.ts | 6 +++---
 packages/jest-reporters/src/VerboseReporter.ts | 5 +++++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/packages/jest-reporters/src/DefaultReporter.ts b/packages/jest-reporters/src/DefaultReporter.ts
index 77b1fbe94b46..2c861ce16f8d 100644
--- a/packages/jest-reporters/src/DefaultReporter.ts
+++ b/packages/jest-reporters/src/DefaultReporter.ts
@@ -43,15 +43,15 @@ export default class DefaultReporter extends BaseReporter {
     this._err = process.stderr.write.bind(process.stderr);
     this._status = new Status();
     this._bufferedOutput = new Set();
-    this._wrapStdio(process.stdout);
-    this._wrapStdio(process.stderr);
+    this.__wrapStdio(process.stdout);
+    this.__wrapStdio(process.stderr);
     this._status.onChange(() => {
       this._clearStatus();
       this._printStatus();
     });
   }
 
-  private _wrapStdio(stream: NodeJS.WritableStream | NodeJS.WriteStream) {
+  protected __wrapStdio(stream: NodeJS.WritableStream | NodeJS.WriteStream) {
     const originalWrite = stream.write;
 
     let buffer: Array<string> = [];
diff --git a/packages/jest-reporters/src/VerboseReporter.ts b/packages/jest-reporters/src/VerboseReporter.ts
index 5d7de322f330..c3f906dde856 100644
--- a/packages/jest-reporters/src/VerboseReporter.ts
+++ b/packages/jest-reporters/src/VerboseReporter.ts
@@ -29,6 +29,11 @@ export default class VerboseReporter extends DefaultReporter {
     this._globalConfig = globalConfig;
   }
 
+  // Verbose mode is for debugging. Buffering of output is undesirable.
+  // See https://github.com/facebook/jest/issues/8208
+  protected __wrapStdio() {
+  }
+
   static filterTestResults(
     testResults: Array<AssertionResult>,
   ): Array<AssertionResult> {