From 15883654f38bec87b2db3c7a7fe56ed73c48682b Mon Sep 17 00:00:00 2001
From: Matei Trandafir <catalin_trand2@yahoo.com>
Date: Thu, 12 Jun 2025 14:48:30 +0000
Subject: [PATCH 01/12] thing

---
 .../src/internal/client/reactivity/props.js       | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index f3111361c051..e102441055f8 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -17,6 +17,8 @@ import { LEGACY_DERIVED_PROP, LEGACY_PROPS, STATE_SYMBOL } from '#client/constan
 import { proxy } from '../proxy.js';
 import { capture_store_binding } from './store.js';
 import { legacy_mode_flag } from '../../flags/index.js';
+import { component_context } from '../context.js';
+import { teardown } from './effects.js';
 
 /**
  * @param {((value?: number) => number)} fn
@@ -159,16 +161,17 @@ export function legacy_rest_props(props, exclude) {
  * The proxy handler for spread props. Handles the incoming array of props
  * that looks like `() => { dynamic: props }, { static: prop }, ..` and wraps
  * them so that the whole thing is passed to the component as the `$$props` argument.
- * @template {Record<string | symbol, unknown>} T
- * @type {ProxyHandler<{ props: Array<T | (() => T)> }>}}
+ * @typedef {Record<string | symbol, unknown>} T
+ * @type {ProxyHandler<{ props: Array<T | (() => T)>, oldProps: T, destroyed: boolean }>}}
  */
 const spread_props_handler = {
 	get(target, key) {
+		if (target.destroyed && key in target.oldProps) return target.oldProps[key]
 		let i = target.props.length;
 		while (i--) {
 			let p = target.props[i];
 			if (is_function(p)) p = p();
-			if (typeof p === 'object' && p !== null && key in p) return p[key];
+			if (typeof p === 'object' && p !== null && key in p) return (target.oldProps[key] = p[key]);
 		}
 	},
 	set(target, key, value) {
@@ -178,7 +181,7 @@ const spread_props_handler = {
 			if (is_function(p)) p = p();
 			const desc = get_descriptor(p, key);
 			if (desc && desc.set) {
-				desc.set(value);
+				desc.set(target.oldProps[key] = value);
 				return true;
 			}
 		}
@@ -238,7 +241,9 @@ const spread_props_handler = {
  * @returns {any}
  */
 export function spread_props(...props) {
-	return new Proxy({ props }, spread_props_handler);
+	let destroyed = false
+	teardown(() => { destroyed = true })
+	return new Proxy({ props, oldProps: {}, get destroyed() { return destroyed } }, spread_props_handler);
 }
 
 /**

From 144d3ccf63fe4dbe9efb84754acb4198e8f09e7f Mon Sep 17 00:00:00 2001
From: Matei Trandafir <catalin_trand2@yahoo.com>
Date: Thu, 12 Jun 2025 15:00:01 +0000
Subject: [PATCH 02/12] format

---
 .../src/internal/client/reactivity/props.js   | 21 ++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index e102441055f8..dd9a17c0e36a 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -166,7 +166,7 @@ export function legacy_rest_props(props, exclude) {
  */
 const spread_props_handler = {
 	get(target, key) {
-		if (target.destroyed && key in target.oldProps) return target.oldProps[key]
+		if (target.destroyed && key in target.oldProps) return target.oldProps[key];
 		let i = target.props.length;
 		while (i--) {
 			let p = target.props[i];
@@ -181,7 +181,7 @@ const spread_props_handler = {
 			if (is_function(p)) p = p();
 			const desc = get_descriptor(p, key);
 			if (desc && desc.set) {
-				desc.set(target.oldProps[key] = value);
+				desc.set((target.oldProps[key] = value));
 				return true;
 			}
 		}
@@ -241,9 +241,20 @@ const spread_props_handler = {
  * @returns {any}
  */
 export function spread_props(...props) {
-	let destroyed = false
-	teardown(() => { destroyed = true })
-	return new Proxy({ props, oldProps: {}, get destroyed() { return destroyed } }, spread_props_handler);
+	let destroyed = false;
+	teardown(() => {
+		destroyed = true;
+	});
+	return new Proxy(
+		{
+			props,
+			oldProps: {},
+			get destroyed() {
+				return destroyed;
+			}
+		},
+		spread_props_handler
+	);
 }
 
 /**

From 3b9fdf982ec95c1a121ef6dd453020c5f1d3d34d Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Thu, 12 Jun 2025 20:50:26 +0300
Subject: [PATCH 03/12] Correctly initialize oldProps so it's not null even if
 it's never read

---
 .../src/internal/client/reactivity/props.js    | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index dd9a17c0e36a..525fb955d0bf 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -17,7 +17,6 @@ import { LEGACY_DERIVED_PROP, LEGACY_PROPS, STATE_SYMBOL } from '#client/constan
 import { proxy } from '../proxy.js';
 import { capture_store_binding } from './store.js';
 import { legacy_mode_flag } from '../../flags/index.js';
-import { component_context } from '../context.js';
 import { teardown } from './effects.js';
 
 /**
@@ -161,8 +160,8 @@ export function legacy_rest_props(props, exclude) {
  * The proxy handler for spread props. Handles the incoming array of props
  * that looks like `() => { dynamic: props }, { static: prop }, ..` and wraps
  * them so that the whole thing is passed to the component as the `$$props` argument.
- * @typedef {Record<string | symbol, unknown>} T
- * @type {ProxyHandler<{ props: Array<T | (() => T)>, oldProps: T, destroyed: boolean }>}}
+ * @typedef {Record<string | symbol, unknown>} AnyProps
+ * @type {ProxyHandler<{ props: Array<AnyProps | (() => AnyProps)>, oldProps: AnyProps, destroyed: boolean }>}}
  */
 const spread_props_handler = {
 	get(target, key) {
@@ -242,13 +241,18 @@ const spread_props_handler = {
  */
 export function spread_props(...props) {
 	let destroyed = false;
-	teardown(() => {
-		destroyed = true;
-	});
+	teardown(() => (destroyed = true));
 	return new Proxy(
 		{
 			props,
-			oldProps: {},
+			oldProps: untrack(() => {
+				const oldProps = {};
+				for (let p of props) {
+					if (typeof p === 'function') p = p();
+					Object.assign(oldProps, p);
+				}
+				return oldProps;
+			}),
 			get destroyed() {
 				return destroyed;
 			}

From d546f1967d3c78dd9164ba0ec9a02494ec6875bd Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Thu, 12 Jun 2025 21:08:09 +0300
Subject: [PATCH 04/12] Make it work even if no spread props are used

---
 .../3-transform/client/visitors/SlotElement.js   |  3 +--
 .../client/visitors/shared/component.js          | 16 ++++++----------
 packages/svelte/src/internal/client/index.js     |  2 +-
 .../src/internal/client/reactivity/props.js      |  2 +-
 4 files changed, 9 insertions(+), 14 deletions(-)

diff --git a/packages/svelte/src/compiler/phases/3-transform/client/visitors/SlotElement.js b/packages/svelte/src/compiler/phases/3-transform/client/visitors/SlotElement.js
index 401cfde42832..43393e5bdc5a 100644
--- a/packages/svelte/src/compiler/phases/3-transform/client/visitors/SlotElement.js
+++ b/packages/svelte/src/compiler/phases/3-transform/client/visitors/SlotElement.js
@@ -54,8 +54,7 @@ export function SlotElement(node, context) {
 	// Let bindings first, they can be used on attributes
 	context.state.init.push(...lets);
 
-	const props_expression =
-		spreads.length === 0 ? b.object(props) : b.call('$.spread_props', b.object(props), ...spreads);
+	const props_expression = b.call('$.props', b.object(props), ...spreads);
 
 	const fallback =
 		node.fragment.nodes.length === 0
diff --git a/packages/svelte/src/compiler/phases/3-transform/client/visitors/shared/component.js b/packages/svelte/src/compiler/phases/3-transform/client/visitors/shared/component.js
index a1c4025d6023..1d52e4ac7c82 100644
--- a/packages/svelte/src/compiler/phases/3-transform/client/visitors/shared/component.js
+++ b/packages/svelte/src/compiler/phases/3-transform/client/visitors/shared/component.js
@@ -4,8 +4,8 @@
 import { dev, is_ignored } from '../../../../../state.js';
 import { get_attribute_chunks, object } from '../../../../../utils/ast.js';
 import * as b from '#compiler/builders';
-import { build_bind_this, memoize_expression, validate_binding } from '../shared/utils.js';
-import { build_attribute_value } from '../shared/element.js';
+import { build_bind_this, memoize_expression, validate_binding } from './utils.js';
+import { build_attribute_value } from './element.js';
 import { build_event_handler } from './events.js';
 import { determine_slot } from '../../../../../utils/slot.js';
 
@@ -399,14 +399,10 @@ export function build_component(node, component_name, context) {
 		push_prop(b.init('$$legacy', b.true));
 	}
 
-	const props_expression =
-		props_and_spreads.length === 0 ||
-		(props_and_spreads.length === 1 && Array.isArray(props_and_spreads[0]))
-			? b.object(/** @type {Property[]} */ (props_and_spreads[0]) || [])
-			: b.call(
-					'$.spread_props',
-					...props_and_spreads.map((p) => (Array.isArray(p) ? b.object(p) : p))
-				);
+	const props_expression = b.call(
+		'$.props',
+		...props_and_spreads.map((p) => (Array.isArray(p) ? b.object(p) : p))
+	);
 
 	/** @param {Expression} node_id */
 	let fn = (node_id) => {
diff --git a/packages/svelte/src/internal/client/index.js b/packages/svelte/src/internal/client/index.js
index 60f9af912060..7a4b045f52d6 100644
--- a/packages/svelte/src/internal/client/index.js
+++ b/packages/svelte/src/internal/client/index.js
@@ -114,7 +114,7 @@ export {
 	prop,
 	rest_props,
 	legacy_rest_props,
-	spread_props,
+	props,
 	update_pre_prop,
 	update_prop
 } from './reactivity/props.js';
diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index 525fb955d0bf..b61a9bf4300e 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -239,7 +239,7 @@ const spread_props_handler = {
  * @param {Array<Record<string, unknown> | (() => Record<string, unknown>)>} props
  * @returns {any}
  */
-export function spread_props(...props) {
+export function props(...props) {
 	let destroyed = false;
 	teardown(() => (destroyed = true));
 	return new Proxy(

From 642105f6efd2df45c1b470113e7d9d1181c6daed Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Thu, 12 Jun 2025 21:30:03 +0300
Subject: [PATCH 05/12] Make it work with out transitions

---
 .../src/internal/client/reactivity/props.js   | 25 +++++++++++++++----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index b61a9bf4300e..14c91017c15f 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -10,14 +10,14 @@ import {
 import { get_descriptor, is_function } from '../../shared/utils.js';
 import { mutable_source, set, source, update } from './sources.js';
 import { derived, derived_safe_equal } from './deriveds.js';
-import { get, captured_signals, untrack } from '../runtime.js';
+import { get, captured_signals, untrack, active_effect } from '../runtime.js';
 import { safe_equals } from './equality.js';
 import * as e from '../errors.js';
 import { LEGACY_DERIVED_PROP, LEGACY_PROPS, STATE_SYMBOL } from '#client/constants';
 import { proxy } from '../proxy.js';
 import { capture_store_binding } from './store.js';
 import { legacy_mode_flag } from '../../flags/index.js';
-import { teardown } from './effects.js';
+import { component_context } from '../context.js';
 
 /**
  * @param {((value?: number) => number)} fn
@@ -240,8 +240,23 @@ const spread_props_handler = {
  * @returns {any}
  */
 export function props(...props) {
-	let destroyed = false;
-	teardown(() => (destroyed = true));
+	let paused = false;
+	const context = component_context;
+	if (active_effect) {
+		(active_effect.transitions ??= []).push({
+			is_global: true,
+			in() {
+				paused = false;
+			},
+			out(callback) {
+				paused = true;
+				callback?.();
+			},
+			stop() {
+				paused = true;
+			}
+		});
+	}
 	return new Proxy(
 		{
 			props,
@@ -254,7 +269,7 @@ export function props(...props) {
 				return oldProps;
 			}),
 			get destroyed() {
-				return destroyed;
+				return (context?.d ?? false) || paused;
 			}
 		},
 		spread_props_handler

From bb239fb965e6f6ce45f8a25db105a6a3f2a5dbcd Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Thu, 12 Jun 2025 21:50:08 +0300
Subject: [PATCH 06/12] Revert #15469

---
 .../svelte/src/internal/client/context.js     |  9 ++----
 .../src/internal/client/reactivity/props.js   | 32 +++----------------
 .../src/internal/client/reactivity/sources.js | 12 -------
 .../svelte/src/internal/client/runtime.js     |  7 +---
 .../svelte/src/internal/client/types.d.ts     |  2 --
 5 files changed, 8 insertions(+), 54 deletions(-)

diff --git a/packages/svelte/src/internal/client/context.js b/packages/svelte/src/internal/client/context.js
index 7c7213b7a2de..f381c62d3a1f 100644
--- a/packages/svelte/src/internal/client/context.js
+++ b/packages/svelte/src/internal/client/context.js
@@ -101,16 +101,15 @@ export function getAllContexts() {
  * @returns {void}
  */
 export function push(props, runes = false, fn) {
-	var ctx = (component_context = {
+	component_context = {
 		p: component_context,
 		c: null,
-		d: false,
 		e: null,
 		m: false,
 		s: props,
 		x: null,
 		l: null
-	});
+	};
 
 	if (legacy_mode_flag && !runes) {
 		component_context.l = {
@@ -121,10 +120,6 @@ export function push(props, runes = false, fn) {
 		};
 	}
 
-	teardown(() => {
-		/** @type {ComponentContext} */ (ctx).d = true;
-	});
-
 	if (DEV) {
 		// component function
 		component_context.function = fn;
diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index 14c91017c15f..125647c44b24 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -240,20 +240,19 @@ const spread_props_handler = {
  * @returns {any}
  */
 export function props(...props) {
-	let paused = false;
-	const context = component_context;
+	let destroyed = false;
 	if (active_effect) {
 		(active_effect.transitions ??= []).push({
 			is_global: true,
 			in() {
-				paused = false;
+				destroyed = false;
 			},
 			out(callback) {
-				paused = true;
+				destroyed = true;
 				callback?.();
 			},
 			stop() {
-				paused = true;
+				destroyed = true;
 			}
 		});
 	}
@@ -269,21 +268,13 @@ export function props(...props) {
 				return oldProps;
 			}),
 			get destroyed() {
-				return (context?.d ?? false) || paused;
+				return destroyed;
 			}
 		},
 		spread_props_handler
 	);
 }
 
-/**
- * @param {Derived} current_value
- * @returns {boolean}
- */
-function has_destroyed_component_ctx(current_value) {
-	return current_value.ctx?.d ?? false;
-}
-
 /**
  * This function is responsible for synchronizing a possibly bound prop with the inner component state.
  * It is used whenever the compiler sees that the component writes to the prop, or when it has a default prop_value.
@@ -417,11 +408,6 @@ export function prop(props, key, flags, fallback) {
 		return (inner_current_value.v = parent_value);
 	});
 
-	// Ensure we eagerly capture the initial value if it's bindable
-	if (bindable) {
-		get(current_value);
-	}
-
 	if (!immutable) current_value.equals = safe_equals;
 
 	return function (/** @type {any} */ value, /** @type {boolean} */ mutation) {
@@ -449,20 +435,12 @@ export function prop(props, key, flags, fallback) {
 					fallback_value = new_value;
 				}
 
-				if (has_destroyed_component_ctx(current_value)) {
-					return value;
-				}
-
 				untrack(() => get(current_value)); // force a synchronisation immediately
 			}
 
 			return value;
 		}
 
-		if (has_destroyed_component_ctx(current_value)) {
-			return current_value.v;
-		}
-
 		return get(current_value);
 	};
 }
diff --git a/packages/svelte/src/internal/client/reactivity/sources.js b/packages/svelte/src/internal/client/reactivity/sources.js
index 40a3e4e77f14..111e8ca7a21d 100644
--- a/packages/svelte/src/internal/client/reactivity/sources.js
+++ b/packages/svelte/src/internal/client/reactivity/sources.js
@@ -14,7 +14,6 @@ import {
 	reaction_sources,
 	check_dirtiness,
 	untracking,
-	is_destroying_effect,
 	push_reaction_value
 } from '../runtime.js';
 import { equals, safe_equals } from './equality.js';
@@ -38,9 +37,6 @@ import { execute_derived } from './deriveds.js';
 
 export let inspect_effects = new Set();
 
-/** @type {Map<Source, any>} */
-export const old_values = new Map();
-
 /**
  * @param {Set<any>} v
  */
@@ -160,14 +156,6 @@ export function set(source, value, should_proxy = false) {
  */
 export function internal_set(source, value) {
 	if (!source.equals(value)) {
-		var old_value = source.v;
-
-		if (is_destroying_effect) {
-			old_values.set(source, value);
-		} else {
-			old_values.set(source, old_value);
-		}
-
 		source.v = value;
 
 		if (DEV && tracing_mode_flag) {
diff --git a/packages/svelte/src/internal/client/runtime.js b/packages/svelte/src/internal/client/runtime.js
index 954406095904..237a7a3c994e 100644
--- a/packages/svelte/src/internal/client/runtime.js
+++ b/packages/svelte/src/internal/client/runtime.js
@@ -25,7 +25,7 @@ import {
 	EFFECT_IS_UPDATING
 } from './constants.js';
 import { flush_tasks } from './dom/task.js';
-import { internal_set, old_values } from './reactivity/sources.js';
+import { internal_set } from './reactivity/sources.js';
 import { destroy_derived_effects, update_derived } from './reactivity/deriveds.js';
 import * as e from './errors.js';
 
@@ -535,7 +535,6 @@ function flush_queued_root_effects() {
 				var collected_effects = process_effects(root_effects[i]);
 				flush_queued_effects(collected_effects);
 			}
-			old_values.clear();
 		}
 	} finally {
 		is_flushing = false;
@@ -800,10 +799,6 @@ export function get(signal) {
 		}
 	}
 
-	if (is_destroying_effect && old_values.has(signal)) {
-		return old_values.get(signal);
-	}
-
 	return signal.v;
 }
 
diff --git a/packages/svelte/src/internal/client/types.d.ts b/packages/svelte/src/internal/client/types.d.ts
index 9703c2aac198..a3156b14dd45 100644
--- a/packages/svelte/src/internal/client/types.d.ts
+++ b/packages/svelte/src/internal/client/types.d.ts
@@ -14,8 +14,6 @@ export type ComponentContext = {
 	p: null | ComponentContext;
 	/** context */
 	c: null | Map<unknown, unknown>;
-	/** destroyed */
-	d: boolean;
 	/** deferred effects */
 	e: null | Array<{
 		fn: () => void | (() => void);

From 8072ab5b44a2f9916ca5b786986ff571a0219bf8 Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Thu, 12 Jun 2025 21:53:19 +0300
Subject: [PATCH 07/12] Lint & format

---
 .../src/internal/client/reactivity/props.js      | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index 125647c44b24..c3a8b3c2fc04 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -161,16 +161,16 @@ export function legacy_rest_props(props, exclude) {
  * that looks like `() => { dynamic: props }, { static: prop }, ..` and wraps
  * them so that the whole thing is passed to the component as the `$$props` argument.
  * @typedef {Record<string | symbol, unknown>} AnyProps
- * @type {ProxyHandler<{ props: Array<AnyProps | (() => AnyProps)>, oldProps: AnyProps, destroyed: boolean }>}}
+ * @type {ProxyHandler<{ props: Array<AnyProps | (() => AnyProps)>, old_props: AnyProps, destroyed: boolean }>}}
  */
 const spread_props_handler = {
 	get(target, key) {
-		if (target.destroyed && key in target.oldProps) return target.oldProps[key];
+		if (target.destroyed && key in target.old_props) return target.old_props[key];
 		let i = target.props.length;
 		while (i--) {
 			let p = target.props[i];
 			if (is_function(p)) p = p();
-			if (typeof p === 'object' && p !== null && key in p) return (target.oldProps[key] = p[key]);
+			if (typeof p === 'object' && p !== null && key in p) return (target.old_props[key] = p[key]);
 		}
 	},
 	set(target, key, value) {
@@ -180,7 +180,7 @@ const spread_props_handler = {
 			if (is_function(p)) p = p();
 			const desc = get_descriptor(p, key);
 			if (desc && desc.set) {
-				desc.set((target.oldProps[key] = value));
+				desc.set((target.old_props[key] = value));
 				return true;
 			}
 		}
@@ -259,13 +259,13 @@ export function props(...props) {
 	return new Proxy(
 		{
 			props,
-			oldProps: untrack(() => {
-				const oldProps = {};
+			old_props: untrack(() => {
+				const old_props = {};
 				for (let p of props) {
 					if (typeof p === 'function') p = p();
-					Object.assign(oldProps, p);
+					Object.assign(old_props, p);
 				}
-				return oldProps;
+				return old_props;
 			}),
 			get destroyed() {
 				return destroyed;

From 587c385724ffe8163fdc3e6ce4951367d189e252 Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Thu, 12 Jun 2025 23:45:53 +0300
Subject: [PATCH 08/12] Much better implementation

---
 .../src/internal/client/reactivity/props.js   | 27 +++++++------------
 1 file changed, 9 insertions(+), 18 deletions(-)

diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index c3a8b3c2fc04..6fa79af20bd0 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -13,7 +13,13 @@ import { derived, derived_safe_equal } from './deriveds.js';
 import { get, captured_signals, untrack, active_effect } from '../runtime.js';
 import { safe_equals } from './equality.js';
 import * as e from '../errors.js';
-import { LEGACY_DERIVED_PROP, LEGACY_PROPS, STATE_SYMBOL } from '#client/constants';
+import {
+	DESTROYED,
+	INERT,
+	LEGACY_DERIVED_PROP,
+	LEGACY_PROPS,
+	STATE_SYMBOL
+} from '#client/constants';
 import { proxy } from '../proxy.js';
 import { capture_store_binding } from './store.js';
 import { legacy_mode_flag } from '../../flags/index.js';
@@ -240,22 +246,7 @@ const spread_props_handler = {
  * @returns {any}
  */
 export function props(...props) {
-	let destroyed = false;
-	if (active_effect) {
-		(active_effect.transitions ??= []).push({
-			is_global: true,
-			in() {
-				destroyed = false;
-			},
-			out(callback) {
-				destroyed = true;
-				callback?.();
-			},
-			stop() {
-				destroyed = true;
-			}
-		});
-	}
+	const effect = active_effect;
 	return new Proxy(
 		{
 			props,
@@ -268,7 +259,7 @@ export function props(...props) {
 				return old_props;
 			}),
 			get destroyed() {
-				return destroyed;
+				return effect ? (effect.f & (DESTROYED | INERT)) !== 0 : false;
 			}
 		},
 		spread_props_handler

From 3ee6b6204ab7b09e46864fefdd3f39f8ddf29214 Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Fri, 13 Jun 2025 00:12:36 +0300
Subject: [PATCH 09/12] Restore some stuff from #15469, but differently

---
 .../src/internal/client/reactivity/props.js   | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index 6fa79af20bd0..d52772250c57 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -266,6 +266,13 @@ export function props(...props) {
 	);
 }
 
+/**
+ * @param {Derived} derived
+ */
+function is_paused_or_destroyed(derived) {
+	return (derived.f & (DESTROYED | INERT)) !== 0;
+}
+
 /**
  * This function is responsible for synchronizing a possibly bound prop with the inner component state.
  * It is used whenever the compiler sees that the component writes to the prop, or when it has a default prop_value.
@@ -399,6 +406,11 @@ export function prop(props, key, flags, fallback) {
 		return (inner_current_value.v = parent_value);
 	});
 
+	// Ensure we eagerly capture the initial value if it's bindable
+	if (bindable) {
+		get(current_value);
+	}
+
 	if (!immutable) current_value.equals = safe_equals;
 
 	return function (/** @type {any} */ value, /** @type {boolean} */ mutation) {
@@ -426,12 +438,20 @@ export function prop(props, key, flags, fallback) {
 					fallback_value = new_value;
 				}
 
+				if (is_paused_or_destroyed(current_value)) {
+					return value;
+				}
+
 				untrack(() => get(current_value)); // force a synchronisation immediately
 			}
 
 			return value;
 		}
 
+		if (is_paused_or_destroyed(current_value)) {
+			return value;
+		}
+
 		return get(current_value);
 	};
 }

From d04e4bb14a787c7e34aecf2dc8ed781c0ac6449b Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Fri, 13 Jun 2025 01:30:27 +0300
Subject: [PATCH 10/12] Update test snapshots

---
 .../bind-component-snippet/_expected/client/index.svelte.js | 6 +++---
 .../samples/bind-this/_expected/client/index.svelte.js      | 4 ++--
 .../_expected/client/index.svelte.js                        | 6 +++---
 .../samples/purity/_expected/client/index.svelte.js         | 4 ++--
 4 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/packages/svelte/tests/snapshot/samples/bind-component-snippet/_expected/client/index.svelte.js b/packages/svelte/tests/snapshot/samples/bind-component-snippet/_expected/client/index.svelte.js
index ba3f4b155a31..a407c84a8ad2 100644
--- a/packages/svelte/tests/snapshot/samples/bind-component-snippet/_expected/client/index.svelte.js
+++ b/packages/svelte/tests/snapshot/samples/bind-component-snippet/_expected/client/index.svelte.js
@@ -18,17 +18,17 @@ export default function Bind_component_snippet($$anchor) {
 	var fragment = root();
 	var node = $.first_child(fragment);
 
-	TextInput(node, {
+	TextInput(node, $.props({
 		get value() {
 			return $.get(value);
 		},
 		set value($$value) {
 			$.set(value, $$value, true);
 		}
-	});
+	}));
 
 	var text_1 = $.sibling(node);
 
 	$.template_effect(() => $.set_text(text_1, ` value: ${$.get(value) ?? ''}`));
 	$.append($$anchor, fragment);
-}
\ No newline at end of file
+}
diff --git a/packages/svelte/tests/snapshot/samples/bind-this/_expected/client/index.svelte.js b/packages/svelte/tests/snapshot/samples/bind-this/_expected/client/index.svelte.js
index dfd32a04e51d..7b9f6d0abfb0 100644
--- a/packages/svelte/tests/snapshot/samples/bind-this/_expected/client/index.svelte.js
+++ b/packages/svelte/tests/snapshot/samples/bind-this/_expected/client/index.svelte.js
@@ -3,5 +3,5 @@ import 'svelte/internal/flags/legacy';
 import * as $ from 'svelte/internal/client';
 
 export default function Bind_this($$anchor) {
-	$.bind_this(Foo($$anchor, { $$legacy: true }), ($$value) => foo = $$value, () => foo);
-}
\ No newline at end of file
+	$.bind_this(Foo($$anchor, $.props({ $$legacy: true })), ($$value) => foo = $$value, () => foo);
+}
diff --git a/packages/svelte/tests/snapshot/samples/function-prop-no-getter/_expected/client/index.svelte.js b/packages/svelte/tests/snapshot/samples/function-prop-no-getter/_expected/client/index.svelte.js
index 762a23754c9b..4bf75eea50c0 100644
--- a/packages/svelte/tests/snapshot/samples/function-prop-no-getter/_expected/client/index.svelte.js
+++ b/packages/svelte/tests/snapshot/samples/function-prop-no-getter/_expected/client/index.svelte.js
@@ -10,7 +10,7 @@ export default function Function_prop_no_getter($$anchor) {
 
 	const plusOne = (num) => num + 1;
 
-	Button($$anchor, {
+	Button($$anchor, $.props({
 		onmousedown: () => $.set(count, $.get(count) + 1),
 		onmouseup,
 		onmouseenter: () => $.set(count, plusOne($.get(count)), true),
@@ -23,5 +23,5 @@ export default function Function_prop_no_getter($$anchor) {
 			$.append($$anchor, text);
 		},
 		$$slots: { default: true }
-	});
-}
\ No newline at end of file
+	}));
+}
diff --git a/packages/svelte/tests/snapshot/samples/purity/_expected/client/index.svelte.js b/packages/svelte/tests/snapshot/samples/purity/_expected/client/index.svelte.js
index a351851875ed..de315b019662 100644
--- a/packages/svelte/tests/snapshot/samples/purity/_expected/client/index.svelte.js
+++ b/packages/svelte/tests/snapshot/samples/purity/_expected/client/index.svelte.js
@@ -16,6 +16,6 @@ export default function Purity($$anchor) {
 
 	var node = $.sibling(p_1, 2);
 
-	Child(node, { prop: encodeURIComponent('hello') });
+	Child(node, $.props({ prop: encodeURIComponent('hello') }));
 	$.append($$anchor, fragment);
-}
\ No newline at end of file
+}

From bd1fb74729f699b2a4585a6cb5e09afe9f752bab Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Fri, 13 Jun 2025 01:30:40 +0300
Subject: [PATCH 11/12] Fix derived pause logic

---
 .../svelte/src/internal/client/reactivity/deriveds.js |  2 +-
 .../svelte/src/internal/client/reactivity/props.js    | 11 ++++++-----
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/packages/svelte/src/internal/client/reactivity/deriveds.js b/packages/svelte/src/internal/client/reactivity/deriveds.js
index e9cea0df3e64..5fa3ffe1c041 100644
--- a/packages/svelte/src/internal/client/reactivity/deriveds.js
+++ b/packages/svelte/src/internal/client/reactivity/deriveds.js
@@ -116,7 +116,7 @@ let stack = [];
  * @param {Derived} derived
  * @returns {Effect | null}
  */
-function get_derived_parent_effect(derived) {
+export function get_derived_parent_effect(derived) {
 	var parent = derived.parent;
 	while (parent !== null) {
 		if ((parent.f & DERIVED) === 0) {
diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index d52772250c57..937f60bf843b 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -9,8 +9,8 @@ import {
 } from '../../../constants.js';
 import { get_descriptor, is_function } from '../../shared/utils.js';
 import { mutable_source, set, source, update } from './sources.js';
-import { derived, derived_safe_equal } from './deriveds.js';
-import { get, captured_signals, untrack, active_effect } from '../runtime.js';
+import { derived, derived_safe_equal, get_derived_parent_effect } from './deriveds.js';
+import { active_effect, captured_signals, get, untrack } from '../runtime.js';
 import { safe_equals } from './equality.js';
 import * as e from '../errors.js';
 import {
@@ -23,7 +23,6 @@ import {
 import { proxy } from '../proxy.js';
 import { capture_store_binding } from './store.js';
 import { legacy_mode_flag } from '../../flags/index.js';
-import { component_context } from '../context.js';
 
 /**
  * @param {((value?: number) => number)} fn
@@ -270,7 +269,9 @@ export function props(...props) {
  * @param {Derived} derived
  */
 function is_paused_or_destroyed(derived) {
-	return (derived.f & (DESTROYED | INERT)) !== 0;
+	const parent = get_derived_parent_effect(derived);
+	if (!parent) return false;
+	return (parent.f & (DESTROYED | INERT)) !== 0;
 }
 
 /**
@@ -449,7 +450,7 @@ export function prop(props, key, flags, fallback) {
 		}
 
 		if (is_paused_or_destroyed(current_value)) {
-			return value;
+			return current_value.v;
 		}
 
 		return get(current_value);

From e2290b59e997663ac0241c1ebfc6746c23714145 Mon Sep 17 00:00:00 2001
From: Matei-Paul Trandafir <matei_trand@yahoo.com>
Date: Fri, 13 Jun 2025 01:55:05 +0300
Subject: [PATCH 12/12] Fix more tests

---
 .../samples/effect-teardown-stale-value/_config.js     |  3 ++-
 .../samples/nested-effect-conflict/_config.js          | 10 +++++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/packages/svelte/tests/runtime-runes/samples/effect-teardown-stale-value/_config.js b/packages/svelte/tests/runtime-runes/samples/effect-teardown-stale-value/_config.js
index 1016ffb43e7e..349487883bf6 100644
--- a/packages/svelte/tests/runtime-runes/samples/effect-teardown-stale-value/_config.js
+++ b/packages/svelte/tests/runtime-runes/samples/effect-teardown-stale-value/_config.js
@@ -14,7 +14,8 @@ export default test({
 			'up',
 			{ foo: false, bar: false },
 			'down',
-			{ foo: false, bar: false },
+			// TODO the test should be deleted as there's no more concept of "teardown stale value"
+			{ foo: true, bar: true },
 			'up',
 			{ foo: true, bar: true }
 		]);
diff --git a/packages/svelte/tests/runtime-runes/samples/nested-effect-conflict/_config.js b/packages/svelte/tests/runtime-runes/samples/nested-effect-conflict/_config.js
index eb631bc9f4bc..a8c16b7008c9 100644
--- a/packages/svelte/tests/runtime-runes/samples/nested-effect-conflict/_config.js
+++ b/packages/svelte/tests/runtime-runes/samples/nested-effect-conflict/_config.js
@@ -10,6 +10,14 @@ export default test({
 		});
 
 		await Promise.resolve();
-		assert.deepEqual(logs, ['top level', 'inner', 0, 'destroy inner', 0, 'destroy outer', 0]);
+		assert.deepEqual(logs, [
+			'top level',
+			'inner',
+			0,
+			'destroy inner',
+			undefined,
+			'destroy outer',
+			undefined
+		]);
 	}
 });

<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.0 Transitional//EN' 'http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd'>
<html xmlns='http://www.w3.org/1999/xhtml'>
<head>
<title>pFad - Phonifier reborn</title>
<meta http-equiv='Content-Type' content='text/html; charset=utf-8' />
</head>
<body>
<h1>Pfad - The Proxy pFad of &#169; 2024 Garber Painting. All rights reserved.</h1>


<!-- Disclaimer -->
<p>Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.</p>
<br>
<p>Alternative Proxies:</p><p><a href="http://clevelandohioweatherforecast.com/php-proxy/index.php?q=https://patch-diff.githubusercontent.com/raw/sveltejs/svelte/pull/16140.patch" target="_blank">Alternative Proxy</a></p><p><a href="http://clevelandohioweatherforecast.com/pFad/index.php?u=https://patch-diff.githubusercontent.com/raw/sveltejs/svelte/pull/16140.patch" target="_blank">pFad Proxy</a></p><p><a href="http://clevelandohioweatherforecast.com/pFad/v3index.php?u=https://patch-diff.githubusercontent.com/raw/sveltejs/svelte/pull/16140.patch" target="_blank">pFad v3 Proxy</a></p><p><a href="http://clevelandohioweatherforecast.com/pFad/v4index.php?u=https://patch-diff.githubusercontent.com/raw/sveltejs/svelte/pull/16140.patch" target="_blank">pFad v4 Proxy</a></p></body>
</html>