perf: reduce call stacks for cleaning up the subscription chain

lib/computed.ts

@@ -21,11 +21,6 @@ export class Computed<T = any> implements Dependency, Subscriber {
 		public getter: (cachedValue?: T) => T
 	) { }
 
-	notifyLostSubs() {
-		Subscriber.clearTrack(this);
-		this.versionOrDirtyLevel = DirtyLevels.Dirty;
-	}
-
 	get(): T {
 		Dependency.linkSubOnly(this);
 		const dirtyLevel = this.versionOrDirtyLevel;
@@ -34,7 +29,7 @@ export class Computed<T = any> implements Dependency, Subscriber {
 			if (this.versionOrDirtyLevel === DirtyLevels.Dirty) {
 				return this.update();
 			}
-		} else if (dirtyLevel === DirtyLevels.Dirty) {
+		} else if (dirtyLevel >= DirtyLevels.Dirty) {
 			return this.update();
 		}
 		return this.cachedValue!;

lib/effect.ts

@@ -25,10 +25,6 @@ export class Effect implements IEffect, Dependency, Subscriber {
 		Dependency.link(this);
 	}
 
-	notifyLostSubs() {
-		Subscriber.clearTrack(this);
-	}
-
 	notify() {
 		const dirtyLevel = this.versionOrDirtyLevel;
 		if (dirtyLevel === DirtyLevels.SideEffectsOnly) {

lib/effectScope.ts

@@ -1,4 +1,4 @@
-import { DirtyLevels, IEffect, Subscriber } from './system.js';
+import { DirtyLevels, IEffect, Link, Subscriber } from './system.js';
 
 export function effectScope() {
 	return new EffectScope();
@@ -27,6 +27,11 @@ export class EffectScope implements IEffect, Subscriber {
 	}
 
 	stop() {
-		Subscriber.clearTrack(this);
+		if (this.deps !== undefined) {
+			Link.releaseDeps(this.deps);
+			Link.release(this.deps);
+			this.deps = undefined;
+		}
+		this.versionOrDirtyLevel = DirtyLevels.None;
 	}
 }

lib/system.ts

@@ -7,7 +7,6 @@ export interface Dependency {
 	subs: Link | undefined;
 	subsTail: Link | undefined;
 	subVersion: number;
-	notifyLostSubs?(): void;
 	update?(): void;
 }
 
@@ -37,6 +36,7 @@ export const enum DirtyLevels {
 	SideEffectsOnly,
 	MaybeDirty,
 	Dirty,
+	Released,
 }
 
 export namespace System {
@@ -45,7 +45,7 @@ export namespace System {
 	export let activeSubsDepth = 0;
 	export let activeSubIsScopeOrNothing = true;
 	export let batchDepth = 0;
-	export let lastSubVersion = DirtyLevels.Dirty + 1;
+	export let lastSubVersion = DirtyLevels.Released + 1;
 	export let queuedEffects: IEffect | undefined = undefined;
 	export let queuedEffectsTail: IEffect | undefined = undefined;
 
@@ -135,8 +135,13 @@ export namespace Link {
 		link.queuedPropagateOrNextReleased = pool;
 		pool = link;
 
-		if (dep.subs === undefined && 'notifyLostSubs' in dep) {
-			dep.notifyLostSubs!();
+		if (dep.subs === undefined && 'deps' in dep) {
+			if (dep.deps !== undefined) {
+				Link.releaseDeps(dep.deps);
+				Link.release(dep.deps);
+				dep.deps = undefined;
+			}
+			dep.versionOrDirtyLevel = DirtyLevels.Released;
 		}
 	}
 }
@@ -479,15 +484,7 @@ export namespace Subscriber {
 		} else {
 			system.activeSubIsScopeOrNothing = true;
 		}
-		postTrack(sub);
-	}
-
-	export function clearTrack(sub: Subscriber) {
-		sub.depsTail = undefined;
-		postTrack(sub);
-	}
 
-	function postTrack(sub: Subscriber) {
 		if (sub.depsTail !== undefined) {
 			Link.releaseDeps(sub.depsTail);
 		} else if (sub.deps !== undefined) {

tests/effect.spec.ts

@@ -14,7 +14,7 @@ test('should clear subscriptions when untracked by all subscribers', () => {
 
 
 	expect(!!b.subs).toBe(true);
-	Subscriber.clearTrack(effect1);
+	Subscriber.endTrack(effect1, Subscriber.startTrack(effect1));
 	expect(!!b.subs).toBe(false);
 });
 

unstable/vue.ts

@@ -4,6 +4,7 @@ import {
 	DirtyLevels,
 	Effect,
 	EffectScope,
+	Link,
 	Signal,
 	Subscriber,
 	System,
@@ -97,7 +98,12 @@ export class ReactiveEffect extends Effect {
 	}
 
 	stop() {
-		Subscriber.clearTrack(this);
+		if (this.deps !== undefined) {
+			Link.releaseDeps(this.deps);
+			Link.release(this.deps);
+			this.deps = undefined;
+		}
+		this.versionOrDirtyLevel = DirtyLevels.None;
 	}
 }