Improve nested effect rerenders in act (-49 B)

Currently `act` relies on a new internal option (`options.hooks`) to detect if a rerender queued up more effects to run. This PR removes `options.hooks` and instead detects if there are new effects to run by continuing to flush and rerender as long as `options.requestAnimationFrame` is invoked.

hooks/src/index.js

@@ -110,7 +110,6 @@ export function useEffect(callback, args) {
 		state._args = args;
 
 		currentComponent.__hooks._pendingEffects.push(state);
-		if (Array.isArray(options.effects)) options.effects.push(state);
 		afterPaint(currentComponent);
 	}
 }
@@ -126,7 +125,6 @@ export function useLayoutEffect(callback, args) {
 	if (argsChanged(state._args, args)) {
 		state._value = callback;
 		state._args = args;
-		if (Array.isArray(options.effects)) options.effects.push(state);
 		currentComponent.__hooks._pendingLayoutEffects.push(state);
 	}
 }
@@ -221,9 +219,6 @@ if (typeof window !== 'undefined') {
 function handleEffects(effects) {
 	effects.forEach(invokeCleanup);
 	effects.forEach(invokeEffect);
-	if (options.effects) {
-		effects.forEach(hook => options.effects = options.effects.filter(h => h!==hook));
-	}
 	return [];
 }
 

test-utils/src/index.js

@@ -10,24 +10,32 @@ export function setupRerender() {
 	return () => options.__test__drainQueue && options.__test__drainQueue();
 }
 
+/**
+ * Run a test function, and flush all effects and rerenders after invoking it
+ * @param {() => void} cb The function under test
+ */
 export function act(cb) {
-	options.effects = [];
 	const previousRequestAnimationFrame = options.requestAnimationFrame;
 	const rerender = setupRerender();
-	let flush;
+
+	/** @type {() => void} */
+	let flush, toFlush;
+
 	// Override requestAnimationFrame so we can flush pending hooks.
 	options.requestAnimationFrame = (fc) => flush = fc;
+
 	// Execute the callback we were passed.
 	cb();
 	rerender();
-	if (flush) {
-		// State COULD be built up flush it.
-		while (options.effects.length > 0) {
-			flush();
-			rerender();
-		}
+
+	while (flush) {
+		toFlush = flush;
+		flush = null;
+
+		toFlush();
+		rerender();
 	}
-	options.effects = undefined;
+
 	options.requestAnimationFrame = previousRequestAnimationFrame;
 }