chore(docs): specify an error message in Timermocks (#12248)

docs/TimerMocks.md

@@ -79,7 +79,13 @@ test('calls the callback after 1 second', () => {
 
 ## Run Pending Timers
 
-There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop… so something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
+There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop, throwing the following error:
+
+```
+Ran 100000 timers, and there are still more! Assuming we've hit an infinite recursion and bailing out...
+```
+
+So something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
 
 ```javascript title="infiniteTimerGame.js"
 'use strict';

website/versioned_docs/version-25.x/TimerMocks.md

@@ -63,7 +63,13 @@ test('calls the callback after 1 second', () => {
 
 ## Run Pending Timers
 
-There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop… so something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
+There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop, throwing the following error:
+
+```
+Ran 100000 timers, and there are still more! Assuming we've hit an infinite recursion and bailing out...
+```
+
+So something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
 
 ```javascript title="infiniteTimerGame.js"
 'use strict';

website/versioned_docs/version-26.x/TimerMocks.md

@@ -63,7 +63,13 @@ test('calls the callback after 1 second', () => {
 
 ## Run Pending Timers
 
-There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop… so something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
+There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop, throwing the following error:
+
+```
+Ran 100000 timers, and there are still more! Assuming we've hit an infinite recursion and bailing out...
+```
+
+So something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
 
 ```javascript title="infiniteTimerGame.js"
 'use strict';

website/versioned_docs/version-27.0/TimerMocks.md

@@ -81,7 +81,13 @@ test('calls the callback after 1 second', () => {
 
 ## Run Pending Timers
 
-There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop… so something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
+There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop, throwing the following error:
+
+```
+Ran 100000 timers, and there are still more! Assuming we've hit an infinite recursion and bailing out...
+```
+
+So something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
 
 ```javascript title="infiniteTimerGame.js"
 'use strict';

website/versioned_docs/version-27.1/TimerMocks.md

@@ -81,7 +81,13 @@ test('calls the callback after 1 second', () => {
 
 ## Run Pending Timers
 
-There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop… so something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
+There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop, throwing the following error:
+
+```
+Ran 100000 timers, and there are still more! Assuming we've hit an infinite recursion and bailing out...
+```
+
+So something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
 
 ```javascript title="infiniteTimerGame.js"
 'use strict';

website/versioned_docs/version-27.2/TimerMocks.md

@@ -60,6 +60,7 @@ All of the following functions need fake timers to be set, either by `jest.useFa
 Another test we might want to write for this module is one that asserts that the callback is called after 1 second. To do this, we're going to use Jest's timer control APIs to fast-forward time right in the middle of the test:
 
 ```javascript
+jest.useFakeTimers();
 test('calls the callback after 1 second', () => {
   const timerGame = require('../timerGame');
   const callback = jest.fn();
@@ -80,7 +81,13 @@ test('calls the callback after 1 second', () => {
 
 ## Run Pending Timers
 
-There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop… so something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
+There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop, throwing the following error:
+
+```
+Ran 100000 timers, and there are still more! Assuming we've hit an infinite recursion and bailing out...
+```
+
+So something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
 
 ```javascript title="infiniteTimerGame.js"
 'use strict';

website/versioned_docs/version-27.4/TimerMocks.md

@@ -81,7 +81,13 @@ test('calls the callback after 1 second', () => {
 
 ## Run Pending Timers
 
-There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop… so something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
+There are also scenarios where you might have a recursive timer -- that is a timer that sets a new timer in its own callback. For these, running all the timers would be an endless loop, throwing the following error:
+
+```
+Ran 100000 timers, and there are still more! Assuming we've hit an infinite recursion and bailing out...
+```
+
+So something like `jest.runAllTimers()` is not desirable. For these cases you might use `jest.runOnlyPendingTimers()`:
 
 ```javascript title="infiniteTimerGame.js"
 'use strict';