Fake timers created inside coroutines which are then closed by coroutine.close/task.cancel still attempt to resume

[nomer888]

This code causes the test to error with 'cannot spawn non-suspended coroutine with arguments', despite being valid when using real timers:

it("timer resume bug", function()
	jest.useFakeTimers()

	local thread
	task.spawn(function()
		task.wait()
		coroutine.close(thread)
	end)
	thread = task.spawn(function()
		task.wait()
		-- no code should execute as this point, and there shouldn't be any errors
	end)

	jest.runAllTimers()
end)

If coroutine.close is swapped with task.cancel, any code after the task.wait() in the thread will still execute, whereas with real timers it won't.

[nomer888]

This patch fixes it for me:

--- a/DevPackages/_Index/jsdotlua_jest-fake-timers@3.10.0/jest-fake-timers/src/init.lua
+++ b/DevPackages/_Index/jsdotlua_jest-fake-timers@3.10.0/jest-fake-timers/src/init.lua
@@ -235,6 +235,7 @@
 	local delayTimeMs = (self._engineFrameTime / 1000) + delayTime * 1000
 	local targetTime = self._mockTimeMs + delayTimeMs
 	local timeout = {
+		thread = coroutine.running(),
 		time = targetTime,
 		callback = callback,
 		args = { ... },
@@ -254,9 +255,18 @@
 	return timeout
 end
 
-local function fakeCancel(self, timeout)
-	for i, timeout_ in self._timeouts do
-		if timeout_ == timeout then
+local function fakeCancel(self, timeoutOrThread)
+	if typeof(timeoutOrThread) == "thread" then
+		realTask.cancel(timeoutOrThread)
+	end
+	for i, timeout in self._timeouts do
+		if timeout == timeoutOrThread or timeout.thread == timeoutOrThread then
+			-- Some timer advancement functions clone the _timeouts array and
+			-- work on that, which we can't modify here. So we also need to
+			-- clear the callback/args to make sure it doesn't do anything
+			timeout.callback = function() end
+			timeout.args = {}
+			timeout.time = self._mockTimeMs
 			table.remove(self._timeouts, i)
 			break
 		end
@@ -267,6 +277,12 @@
 	local running = coroutine.running()
 	local clock = fakeClock(self)
 	fakeDelay(self, timeToWait or 0, function()
+		if coroutine.status(running) == "dead" then
+			-- This was probably canceled by coroutine.close, which we don't
+			-- mock. We can just treat it like task.cancel and return
+			fakeCancel(self, running)
+			return
+		end
 		task.spawn(running, fakeClock(self) - clock)
 	end)
 	return coroutine.yield()