chore: remove signal field from effects (#10984)

Author: trueadm

packages/svelte/src/internal/client/reactivity/deriveds.js

@@ -3,14 +3,14 @@ import { CLEAN, DERIVED, DESTROYED, DIRTY, MAYBE_DIRTY, UNOWNED } from '../const
 import {
 	current_reaction,
 	current_effect,
-	destroy_children,
 	remove_reactions,
 	set_signal_status,
 	mark_reactions,
 	current_skip_reaction,
 	execute_reaction_fn
 } from '../runtime.js';
 import { equals, safe_equals } from './equality.js';
+import { destroy_effect } from './effects.js';
 
 export let updating_derived = false;
 
@@ -42,10 +42,11 @@ export function derived(fn) {
 	}
 
 	if (current_reaction !== null && (current_reaction.f & DERIVED) !== 0) {
-		if (current_reaction.deriveds === null) {
-			current_reaction.deriveds = [signal];
+		var current_derived = /** @type {import('#client').Derived<V>} */ (current_reaction);
+		if (current_derived.deriveds === null) {
+			current_derived.deriveds = [signal];
 		} else {
-			current_reaction.deriveds.push(signal);
+			current_derived.deriveds.push(signal);
 		}
 	}
 
@@ -64,6 +65,27 @@ export function derived_safe_equal(fn) {
 	return signal;
 }
 
+/**
+ * @param {import('./types.js').Derived} signal
+ * @returns {void}
+ */
+function destroy_derived_children(signal) {
+	// TODO: should it be possible to create effects in deriveds given they're meant to be pure?
+	if (signal.effects) {
+		for (var i = 0; i < signal.effects.length; i += 1) {
+			destroy_effect(signal.effects[i]);
+		}
+		signal.effects = null;
+	}
+
+	if (signal.deriveds) {
+		for (i = 0; i < signal.deriveds.length; i += 1) {
+			destroy_derived(signal.deriveds[i]);
+		}
+		signal.deriveds = null;
+	}
+}
+
 /**
  * @param {import('#client').Derived} derived
  * @param {boolean} force_schedule
@@ -72,7 +94,7 @@ export function derived_safe_equal(fn) {
 export function update_derived(derived, force_schedule) {
 	var previous_updating_derived = updating_derived;
 	updating_derived = true;
-	destroy_children(derived);
+	destroy_derived_children(derived);
 	var value = execute_reaction_fn(derived);
 	updating_derived = previous_updating_derived;
 
@@ -98,7 +120,7 @@ export function update_derived(derived, force_schedule) {
  * @returns {void}
  */
 export function destroy_derived(signal) {
-	destroy_children(signal);
+	destroy_derived_children(signal);
 	remove_reactions(signal, 0);
 	set_signal_status(signal, DESTROYED);
 

packages/svelte/src/internal/client/reactivity/effects.js

@@ -46,7 +46,6 @@ function create_effect(type, fn, sync) {
 		f: type | DIRTY,
 		fn,
 		effects: null,
-		deriveds: null,
 		teardown: null,
 		ctx: current_component_context,
 		transitions: null

packages/svelte/src/internal/client/reactivity/types.d.ts

@@ -23,13 +23,13 @@ export interface Reaction extends Signal {
 	deps: null | Value[];
 	/** Effects created inside this signal */
 	effects: null | Effect[];
-	/** Deriveds created inside this signal */
-	deriveds: null | Derived[];
 }
 
 export interface Derived<V = unknown> extends Value<V>, Reaction {
 	/** The derived function */
 	fn: () => V;
+	/** Deriveds created inside this signal */
+	deriveds: null | Derived[];
 }
 
 export interface Effect extends Reaction {

packages/svelte/src/internal/client/runtime.js

@@ -349,7 +349,7 @@ export function remove_reactions(signal, start_index) {
 }
 
 /**
- * @param {import('./types.js').Reaction} signal
+ * @param {import('./types.js').Effect} signal
  * @returns {void}
  */
 export function destroy_children(signal) {
@@ -359,13 +359,6 @@ export function destroy_children(signal) {
 		}
 		signal.effects = null;
 	}
-
-	if (signal.deriveds) {
-		for (i = 0; i < signal.deriveds.length; i += 1) {
-			destroy_derived(signal.deriveds[i]);
-		}
-		signal.deriveds = null;
-	}
 }
 
 /**