From 81519adff84b1883247025920db782dc83a3b27a Mon Sep 17 00:00:00 2001
From: "grigas.petraitis" <grigas.petraitis@bentley.com>
Date: Mon, 17 Sep 2018 10:56:12 +0300
Subject: [PATCH 1/3] fix(waitForElement): ensure waitForElement disconnects
 MutationObserver at the right time

---
 src/__tests__/wait-for-element.js | 45 +++++++++++++++++++++++++++++++
 src/wait-for-element.js           |  2 +-
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/src/__tests__/wait-for-element.js b/src/__tests__/wait-for-element.js
index 6c655855..1feaa619 100644
--- a/src/__tests__/wait-for-element.js
+++ b/src/__tests__/wait-for-element.js
@@ -312,3 +312,48 @@ test('it returns immediately if the callback returns the value before any mutati
 
   return promise
 })
+
+test('does not get into infinite setTimeout loop after MutationObserver notification', async () => {
+  const {container} = render(`<div data-testid="initial-element"></div>`)
+
+  let didMakeMutation = false
+  const callback = jest.fn(() => didMakeMutation).mockName('callback')
+  const successHandler = jest.fn().mockName('successHandler')
+  const errorHandler = jest.fn().mockName('errorHandler')
+  jest.useFakeTimers()
+
+  const promise = waitForElement(callback, {
+    container,
+    timeout: 70,
+    mutationObserverOptions: {attributes: true},
+  }).then(successHandler, errorHandler)
+
+  // Expect 2 timeouts to be scheduled:
+  // - waitForElement timeout
+  // - MutationObserver timeout
+  expect(setTimeout).toHaveBeenCalledTimes(2)
+
+  // One synchronous `callback` call is expected.
+  expect(callback).toHaveBeenCalledTimes(1)
+  expect(successHandler).toHaveBeenCalledTimes(0)
+  expect(errorHandler).toHaveBeenCalledTimes(0)
+
+  // Make a mutation so MutationObserver calls out callback
+  container.setAttribute('data-test-attribute', 'something changed')
+  didMakeMutation = true
+
+  // Advance timer to expire MutationObserver timeout
+  jest.advanceTimersByTime(50)
+  jest.runAllImmediates()
+  await promise
+  expect(setTimeout).toHaveBeenCalledTimes(3)
+
+  // Expect callback and successHandler to be called
+  expect(callback).toHaveBeenCalledTimes(2)
+  expect(successHandler).toHaveBeenCalledTimes(1)
+  expect(errorHandler).toHaveBeenCalledTimes(0)
+
+  // Expect no more setTimeout calls
+  jest.advanceTimersByTime(100)
+  expect(setTimeout).toHaveBeenCalledTimes(3)
+})
diff --git a/src/wait-for-element.js b/src/wait-for-element.js
index 0ae3ba41..1bed5511 100644
--- a/src/wait-for-element.js
+++ b/src/wait-for-element.js
@@ -18,7 +18,7 @@ function waitForElement(
     let lastError, observer, timer // eslint-disable-line prefer-const
     function onDone(error, result) {
       clearTimeout(timer)
-      observer.disconnect()
+      setImmediate(() => observer.disconnect())
       if (error) {
         reject(error)
       } else {

From 00b018d6d0acbee2a7cc258da2b1f32fee3d8a11 Mon Sep 17 00:00:00 2001
From: "Kent C. Dodds" <kent+github@doddsfamily.us>
Date: Mon, 17 Sep 2018 11:38:21 -0600
Subject: [PATCH 2/3] test to make sure the test fails without changes

---
 src/wait-for-element.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/wait-for-element.js b/src/wait-for-element.js
index 1bed5511..0ae3ba41 100644
--- a/src/wait-for-element.js
+++ b/src/wait-for-element.js
@@ -18,7 +18,7 @@ function waitForElement(
     let lastError, observer, timer // eslint-disable-line prefer-const
     function onDone(error, result) {
       clearTimeout(timer)
-      setImmediate(() => observer.disconnect())
+      observer.disconnect()
       if (error) {
         reject(error)
       } else {

From 898450144f18ff42f835eab38be1159341b9954f Mon Sep 17 00:00:00 2001
From: "Kent C. Dodds" <kent+github@doddsfamily.us>
Date: Mon, 17 Sep 2018 11:41:23 -0600
Subject: [PATCH 3/3] restore original solution

---
 src/wait-for-element.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/wait-for-element.js b/src/wait-for-element.js
index 0ae3ba41..1bed5511 100644
--- a/src/wait-for-element.js
+++ b/src/wait-for-element.js
@@ -18,7 +18,7 @@ function waitForElement(
     let lastError, observer, timer // eslint-disable-line prefer-const
     function onDone(error, result) {
       clearTimeout(timer)
-      observer.disconnect()
+      setImmediate(() => observer.disconnect())
       if (error) {
         reject(error)
       } else {