Simplify test case a bit

packages/react/runtime/test/useSignals.test.tsx

@@ -525,46 +525,37 @@ describe("useSignals", () => {
 		expect(scratch.innerHTML).to.equal("<div>Hello John</div>");
 	});
 
-	it.only("(unmanaged) should work with rerenders that update signals before async final cleanup", async () => {
+	it.only("(unmanaged) React 16 should work with rerenders that update signals before async final cleanup", async () => {
 		// Cursed/problematic ordering:
 		// 1. onClick callback
 		// 1a. call setState (queues sync work at end of event handler in React)
-		// 2b. await Promise.resolve();
-		// 3. React flushes sync callbacks and rerenders component
-		// 3a. Start useSignals effect & start batch
-		// 4. Resolve promises resumes and sets signal value
-		// 4a. In batch, so mark subscribers as needing update
-		// 5. useSignals finalCleanup runs
-		// 5a. finishEffect runs
-		// 5aa. endBatch and call subscribers with signal update
-		// 5ab. usSignals + useSyncExternalStore calls onChangeNotifyReact
-		// 5ac. React sync rerenders component
-		// 5ad. useSignals effect runs
-		// 5ae. finishEffect called again (evalContext == null but this == effectInstance)
+		// 1b. await Promise.resolve();
+		// 2. React flushes sync callbacks and rerenders component
+		// 2a. Start useSignals effect, set evalContext, & start batch
+		// 3. Resolve promises resumes and sets signal value
+		// 3a. In batch, so mark subscribers as needing update
+		// 4. useSignals finalCleanup runs
+		// 4a. endEffect runs and clears evalContext
+		// 4aa. endBatch and call subscribers with signal update
+		// 4ab. usSignals' useSyncExternalStore calls onChangeNotifyReact
+		// 4ac. React sync rerenders component
+		// 4ad. useSignals effect runs
+		// 4ae. finishEffect called again (evalContext == null but this == effectInstance)
 		// BOOM! Error thrown
 
-		let asyncOp: Promise<void>;
-		// const delay = (ms = 0) => new Promise(r => setTimeout(r, ms));
-		const delay = () => Promise.resolve();
-		async function testAsync(cb: () => any) {
-			asyncOp = delay().then(() => cb());
-		}
-
 		const count = signal(0);
 
 		function C() {
 			console.log("rendering C");
 			useSignals();
 			const [loading, setLoading] = useState(false);
 
-			const onClick = () => {
+			const onClick = async () => {
 				setLoading(true);
 				console.log("onClick");
-				testAsync(() => {
-					console.log("setSignal");
-					count.value += 1;
-					// setLoading(false);
-				});
+				await Promise.resolve();
+				console.log("setSignal");
+				count.value += 1;
 			};
 
 			return (
@@ -587,9 +578,7 @@ describe("useSignals", () => {
 			`<p>0</p><button disabled="">loading...</button>`
 		);
 
-		console.log("wait start");
-		await asyncOp!;
-		console.log("wait finish");
+		// Do I need to do something here before this assertion?
 		expect(scratch.innerHTML).to.equal("<p>1</p><button>increment</button>");
 	});