refactor: no longer use activeTrackId, activeScopeTrackId

pub/alien_signals/lib/src/computed.dart

@@ -41,9 +41,6 @@ class Computed<T> implements IComputed, ISignal<T> {
   @override
   SubscriberFlags flags = SubscriberFlags.dirty;
 
-  @override
-  int? lastTrackedId = 0;
-
   @override
   Link? subs;
 
@@ -60,13 +57,9 @@ class Computed<T> implements IComputed, ISignal<T> {
       shallowPropagate(subs);
     }
 
-    if (activeTrackId != 0) {
-      if (lastTrackedId != activeTrackId) {
-        lastTrackedId = activeTrackId;
-        link(this, activeSub!);
-      }
-    } else if (activeScopeTrackId != 0 && lastTrackedId != activeScopeTrackId) {
-      lastTrackedId = activeScopeTrackId;
+    if (activeSub != null) {
+      link(this, activeSub!);
+    } else if (activeEffectScope != null) {
       link(this, activeEffectScope!);
     }
 
@@ -76,8 +69,8 @@ class Computed<T> implements IComputed, ISignal<T> {
   @override
   bool update() {
     final prevSub = activeSub;
-    final prevTrackId = activeTrackId;
-    setActiveSub(this, nextTrackId());
+
+    setActiveSub(this);
     startTrack(this);
 
     try {
@@ -90,7 +83,7 @@ class Computed<T> implements IComputed, ISignal<T> {
 
       return false;
     } finally {
-      setActiveSub(prevSub, prevTrackId);
+      setActiveSub(prevSub);
       endTrack(this);
     }
   }

pub/alien_signals/lib/src/effect.dart

@@ -4,31 +4,13 @@ import 'system.dart';
 /// The currently active subscriber.
 Subscriber? activeSub;
 
-/// The ID of the currently active track.
-int activeTrackId = 0;
-
-/// The ID of the last track that was used.
-int lastTrackId = 0;
-
-/// Sets the currently active subscriber and track ID.
+/// Sets the currently active subscriber.
 ///
-/// This function updates the global `activeSub` and `activeTrackId` variables
-/// to the provided `sub` and `trackId` respectively.
+/// This function updates the global `activeSub` variable to the provided `sub`.
 ///
 /// @param sub The subscriber to set as active.
-/// @param trackId The track ID to set as active.
-void setActiveSub(Subscriber? sub, int trackId) {
+void setActiveSub(Subscriber? sub) {
   activeSub = sub;
-  activeTrackId = trackId;
-}
-
-/// Generates the next track ID.
-///
-/// This function increments the global `lastTrackId` by one and returns the new value.
-///
-/// @returns The next track ID.
-int nextTrackId() {
-  return ++lastTrackId;
 }
 
 /// Executes a function without tracking dependencies.
@@ -48,12 +30,11 @@ int nextTrackId() {
 /// ```
 T untrack<T>(T Function() fn) {
   final prevSub = activeSub;
-  final prevTrackId = activeTrackId;
-  setActiveSub(null, 0);
+  setActiveSub(null);
   try {
     return fn();
   } finally {
-    setActiveSub(prevSub, prevTrackId);
+    setActiveSub(prevSub);
   }
 }
 
@@ -87,9 +68,9 @@ Effect<T> effect<T>(T Function() fn) {
 class Effect<T> implements IEffect, Dependency {
   /// {@macro alien_signals.effect}
   Effect(this.fn) {
-    if (activeTrackId != 0) {
+    if (activeSub != null) {
       link(this, activeSub!);
-    } else if (activeScopeTrackId != 0) {
+    } else if (activeEffectScope != null) {
       link(this, activeEffectScope!);
     }
   }
@@ -106,9 +87,6 @@ class Effect<T> implements IEffect, Dependency {
   @override
   SubscriberFlags flags = SubscriberFlags.dirty;
 
-  @override
-  int? lastTrackedId;
-
   @override
   IEffect? nextNotify;
 
@@ -142,13 +120,12 @@ class Effect<T> implements IEffect, Dependency {
   /// @returns The result of the effect function.
   T run() {
     final prevSub = activeSub;
-    final prevTrackId = activeTrackId;
-    setActiveSub(this, nextTrackId());
+    setActiveSub(this);
     startTrack(this);
     try {
       return fn();
     } finally {
-      setActiveSub(prevSub, prevTrackId);
+      setActiveSub(prevSub);
       endTrack(this);
     }
   }

pub/alien_signals/lib/src/effect_scope.dart

@@ -4,38 +4,30 @@ import 'system.dart';
 /// The currently active effect scope, if any.
 EffectScope? activeEffectScope;
 
-/// The track ID associated with the currently active effect scope.
-int activeScopeTrackId = 0;
-
-/// Sets the currently active effect scope and its associated track ID.
+/// Sets the currently active effect scope.
 ///
-/// This function updates the global variables [activeEffectScope] and
-/// [activeScopeTrackId] with the provided [scope] and [trackId] respectively.
+/// This function updates the global variable [activeEffectScope] with the provided [scope].
 ///
-/// - Parameters:
-///   - scope: The effect scope to set as active.
-///   - trackId: The track ID associated with the effect scope.
-void setActiveScope(EffectScope? scope, int trackId) {
+/// - Parameter scope: The effect scope to set as active.
+void setActiveScope(EffectScope? scope) {
   activeEffectScope = scope;
-  activeScopeTrackId = trackId;
 }
 
 /// Executes a function without tracking the current effect scope.
 ///
-/// This function temporarily sets the [activeEffectScope] and [activeScopeTrackId]
-/// to `null` and `0` respectively, executes the provided function [fn], and then
-/// restores the previous values of [activeEffectScope] and [activeScopeTrackId].
+/// This function temporarily disables scope tracking by setting [activeEffectScope]
+/// to `null`, executes the provided function [fn], and restores the previous
+/// effect scope afterwards.
 ///
-/// - Parameter fn: The function to execute without tracking the current effect scope.
+/// - Parameter [fn]: The function to execute without tracking the current effect scope.
 /// - Returns: The result of the executed function [fn].
 T untrackScope<T>(T Function() fn) {
   final prevSub = activeEffectScope;
-  final prevTrackId = activeScopeTrackId;
-  setActiveScope(null, 0);
+  setActiveScope(null);
   try {
     return fn();
   } finally {
-    setActiveScope(prevSub, prevTrackId);
+    setActiveScope(prevSub);
   }
 }
 
@@ -80,11 +72,6 @@ class EffectScope implements IEffect {
   @override
   IEffect? nextNotify;
 
-  /// The track ID associated with this effect scope.
-  ///
-  /// This ID is used to uniquely identify the effect scope within the system.
-  int trackId = nextTrackId();
-
   @override
   void notify() {
     if ((flags & SubscriberFlags.innerEffectsPending) != 0) {
@@ -95,14 +82,12 @@ class EffectScope implements IEffect {
 
   T run<T>(T Function() fn) {
     final prevSub = activeEffectScope;
-    final prevTrackId = activeScopeTrackId;
     activeEffectScope = this;
-    activeScopeTrackId = trackId;
+
     try {
       return fn();
     } finally {
       activeEffectScope = prevSub;
-      activeScopeTrackId = prevTrackId;
     }
   }
 

pub/alien_signals/lib/src/signal.dart

@@ -31,9 +31,6 @@ class Signal<T> implements Dependency, IWritableSignal<T> {
   /// The current value held by the signal.
   T currentValue;
 
-  @override
-  int? lastTrackedId = 0;
-
   @override
   Link? subs;
 
@@ -42,8 +39,7 @@ class Signal<T> implements Dependency, IWritableSignal<T> {
 
   @override
   T get() {
-    if (activeTrackId != 0 && lastTrackedId != activeTrackId) {
-      lastTrackedId = activeTrackId;
+    if (activeSub != null) {
       link(this, activeSub!);
     }
 

pub/alien_signals/lib/src/system.dart

@@ -22,9 +22,6 @@ abstract interface class Dependency {
 
   /// The tail of the linked list of subscribers.
   Link? subsTail;
-
-  /// The ID of the last tracked dependency.
-  int? lastTrackedId;
 }
 
 /// [Subscriber] flags type def.
@@ -174,13 +171,24 @@ void _drainQueuedEffects() {
 /// Create or reuse a link between a dependency and subscriber
 void link(Dependency dep, Subscriber sub) {
   final currentDep = sub.depsTail;
-  final nextDep = currentDep != null ? currentDep.nextDep : sub.deps;
+  if (currentDep != null && currentDep.dep == dep) {
+    return;
+  }
 
+  final nextDep = currentDep != null ? currentDep.nextDep : sub.deps;
   if (nextDep != null && nextDep.dep == dep) {
     sub.depsTail = nextDep;
-  } else {
-    _linkNewDep(dep, sub, nextDep, currentDep);
+    return;
   }
+
+  final depLastSub = dep.subsTail;
+  if (depLastSub != null &&
+      depLastSub.sub == sub &&
+      _isValidLink(depLastSub, sub)) {
+    return;
+  }
+
+  _linkNewDep(dep, sub, nextDep, currentDep);
 }
 
 void _linkNewDep(
@@ -451,21 +459,25 @@ bool checkDirty(Link? link) {
 /// Start tracking dependencies for a subscriber
 void startTrack(Subscriber sub) {
   sub.depsTail = null;
-  sub.flags = SubscriberFlags.tracking;
+  sub.flags =
+      (sub.flags & ~(SubscriberFlags.recursed | SubscriberFlags.notified)) |
+          SubscriberFlags.tracking;
 }
 
 /// End tracking dependencies for a subscriber
 void endTrack(Subscriber sub) {
   final depsTail = sub.depsTail;
   if (depsTail != null) {
-    if (depsTail.nextDep != null) {
-      _clearTrack(depsTail.nextDep);
+    final nextDep = depsTail.nextDep;
+    if (nextDep != null) {
+      _clearTrack(nextDep);
       depsTail.nextDep = null;
     }
   } else if (sub.deps != null) {
     _clearTrack(sub.deps);
     sub.deps = null;
   }
+
   sub.flags &= ~SubscriberFlags.tracking;
 }
 
@@ -481,7 +493,6 @@ void _clearTrack(Link? link) {
       link.nextSub = null;
     } else {
       dep.subsTail = prevSub;
-      dep.lastTrackedId = 0;
     }
 
     if (prevSub != null) {
@@ -496,14 +507,11 @@ void _clearTrack(Link? link) {
     _linkPool = link;
 
     if (dep.subs == null && dep is Subscriber) {
-      if (dep is IEffect) {
-        (dep as Subscriber).flags = SubscriberFlags.none;
-      } else {
-        final depFlags = (dep as Subscriber).flags;
-        if ((depFlags & SubscriberFlags.dirty) == 0) {
-          (dep as Subscriber).flags = depFlags | SubscriberFlags.dirty;
-        }
+      final depFlags = (dep as Subscriber).flags;
+      if (depFlags & SubscriberFlags.dirty == 0) {
+        (dep as Subscriber).flags = depFlags | SubscriberFlags.dirty;
       }
+
       final depDeps = (dep as Subscriber).deps;
       if (depDeps != null) {
         link = depDeps;