From 4f7cd0317545efdd0fb652841f2460753d485461 Mon Sep 17 00:00:00 2001
From: Saurav M H <sauravhiremath@gmail.com>
Date: Wed, 30 Jun 2021 17:20:53 +0000
Subject: [PATCH] fix: bigInt serialization

---
 packages/jest-worker/src/index.ts                 | 7 +++++++
 packages/jest-worker/src/workers/messageParent.ts | 3 ++-
 packages/jest-worker/src/workers/processChild.ts  | 3 ++-
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/packages/jest-worker/src/index.ts b/packages/jest-worker/src/index.ts
index 50be5683dfba..a563d79781e3 100644
--- a/packages/jest-worker/src/index.ts
+++ b/packages/jest-worker/src/index.ts
@@ -45,6 +45,13 @@ function getExposedMethods(
   return exposedMethods;
 }
 
+export function serializeBigInt(data: unknown): unknown {
+  if (typeof data === 'bigint') {
+    return data.toString();
+  }
+  return data;
+}
+
 /**
  * The Jest farm (publicly called "Worker") is a class that allows you to queue
  * methods across multiple child processes, in order to parallelize work. This
diff --git a/packages/jest-worker/src/workers/messageParent.ts b/packages/jest-worker/src/workers/messageParent.ts
index d4a389055fc0..662e51db1643 100644
--- a/packages/jest-worker/src/workers/messageParent.ts
+++ b/packages/jest-worker/src/workers/messageParent.ts
@@ -5,6 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import {serializeBigInt} from '../index';
 import {PARENT_MESSAGE_CUSTOM} from '../types';
 
 const isWorkerThread: boolean = (() => {
@@ -29,7 +30,7 @@ export default function messageParent(
     // ! is safe due to `null` check in `isWorkerThread`
     parentPort!.postMessage([PARENT_MESSAGE_CUSTOM, message]);
   } else if (typeof parentProcess.send === 'function') {
-    parentProcess.send([PARENT_MESSAGE_CUSTOM, message]);
+    parentProcess.send([PARENT_MESSAGE_CUSTOM, serializeBigInt(message)]);
   } else {
     throw new Error('"messageParent" can only be used inside a worker');
   }
diff --git a/packages/jest-worker/src/workers/processChild.ts b/packages/jest-worker/src/workers/processChild.ts
index 64d29e19e132..5359b3f5f765 100644
--- a/packages/jest-worker/src/workers/processChild.ts
+++ b/packages/jest-worker/src/workers/processChild.ts
@@ -5,6 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import {serializeBigInt} from '../index';
 import {
   CHILD_MESSAGE_CALL,
   CHILD_MESSAGE_END,
@@ -64,7 +65,7 @@ function reportSuccess(result: unknown) {
     throw new Error('Child can only be used on a forked process');
   }
 
-  process.send([PARENT_MESSAGE_OK, result]);
+  process.send([PARENT_MESSAGE_OK, serializeBigInt(result)]);
 }
 
 function reportClientError(error: Error) {