From 87d2195120cbfcd30971aeb5728376b460330fcb Mon Sep 17 00:00:00 2001
From: Philipp Fritsche <ph.fritsche@gmail.com>
Date: Thu, 22 Apr 2021 11:20:41 +0200
Subject: [PATCH 1/2] fix: check if `jest.useRealTimers` exists

---
 src/helpers.js | 28 +++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/src/helpers.js b/src/helpers.js
index 559e39d2..699b3460 100644
--- a/src/helpers.js
+++ b/src/helpers.js
@@ -5,13 +5,18 @@ const TEXT_NODE = 3
 
 // Currently this fn only supports jest timers, but it could support other test runners in the future.
 function runWithRealTimers(callback) {
-  // istanbul ignore else
-  if (typeof jest !== 'undefined') {
-    return runWithJestRealTimers(callback).callbackReturnValue
-  }
+  return hasJestTimers()
+    ? runWithJestRealTimers(callback).callbackReturnValue
+    : // istanbul ignore next
+      callback()
+}
 
-  // istanbul ignore next
-  return callback()
+function hasJestTimers() {
+  return (
+    jest !== undefined &&
+    jest !== null &&
+    typeof jest.useRealTimers === 'function'
+  )
 }
 
 function runWithJestRealTimers(callback) {
@@ -50,13 +55,10 @@ function runWithJestRealTimers(callback) {
 }
 
 function jestFakeTimersAreEnabled() {
-  // istanbul ignore else
-  if (typeof jest !== 'undefined') {
-    return runWithJestRealTimers(() => {}).usedFakeTimers
-  }
-
-  // istanbul ignore next
-  return false
+  return hasJestTimers()
+    ? runWithJestRealTimers(() => {}).usedFakeTimers
+    : // istanbul ignore next
+      false
 }
 
 // we only run our tests in node, and setImmediate is supported in node.

From 80a6af82d298f8d039670645b9a627dae8655664 Mon Sep 17 00:00:00 2001
From: Philipp Fritsche <ph.fritsche@gmail.com>
Date: Thu, 22 Apr 2021 12:02:19 +0200
Subject: [PATCH 2/2] Update src/helpers.js

Co-authored-by: Sebastian Silbermann <silbermann.sebastian@gmail.com>
---
 src/helpers.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/helpers.js b/src/helpers.js
index 699b3460..4536ddd5 100644
--- a/src/helpers.js
+++ b/src/helpers.js
@@ -13,7 +13,7 @@ function runWithRealTimers(callback) {
 
 function hasJestTimers() {
   return (
-    jest !== undefined &&
+    typeof jest !== 'undefined' &&
     jest !== null &&
     typeof jest.useRealTimers === 'function'
   )