rename effect.y to effect.ondestroy

packages/svelte/src/internal/client/dom/blocks/await.js

@@ -175,7 +175,7 @@ export function await_block(anchor_node, input, pending_fn, then_fn, catch_fn) {
 		block,
 		false
 	);
-	await_effect.y = () => {
+	await_effect.ondestroy = () => {
 		let render = current_render;
 		latest_token = {};
 		while (render !== null) {

packages/svelte/src/internal/client/dom/blocks/each.js

@@ -261,7 +261,7 @@ function each(anchor_node, collection, flags, key_fn, render_fn, fallback_fn, re
 		set_current_hydration_fragment([]);
 	}
 
-	each.y = () => {
+	each.ondestroy = () => {
 		const flags = block.f;
 		const anchor_node = block.a;
 		const is_controlled = (flags & EACH_IS_CONTROLLED) !== 0;

packages/svelte/src/internal/client/dom/blocks/if.js

@@ -167,7 +167,7 @@ export function if_block(anchor_node, condition_fn, consequent_fn, alternate_fn)
 		true
 	);
 	block.ae = alternate_effect;
-	if_effect.y = () => {
+	if_effect.ondestroy = () => {
 		if (consequent_dom !== null) {
 			remove(consequent_dom);
 		}

packages/svelte/src/internal/client/dom/blocks/key.js

@@ -122,7 +122,7 @@ export function key_block(anchor_node, key, render_fn) {
 	// we trigger the effect after.
 	render();
 	mounted = true;
-	key_effect.y = () => {
+	key_effect.ondestroy = () => {
 		let render = current_render;
 		while (render !== null) {
 			const dom = render.d;

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

@@ -39,7 +39,7 @@ function create_effect(type, fn, sync, block, schedule) {
 		teardown: null,
 		w: 0,
 		ctx: current_component_context,
-		y: null
+		ondestroy: null
 	};
 
 	if (current_effect !== null) {
@@ -245,10 +245,10 @@ export function render_effect(fn, block = current_block, managed = false, sync =
  */
 export function destroy_effect(signal) {
 	const teardown = signal.teardown;
-	const destroy = signal.y;
+	const destroy = signal.ondestroy;
 	destroy_references(signal);
 	remove_reactions(signal, 0);
-	signal.fn = signal.effects = signal.y = signal.ctx = signal.block = signal.deps = null;
+	signal.fn = signal.effects = signal.ondestroy = signal.ctx = signal.block = signal.deps = null;
 	set_signal_status(signal, DESTROYED);
 	if (destroy !== null) {
 		if (is_array(destroy)) {

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

@@ -40,7 +40,7 @@ export interface Effect extends Reaction {
 	/** context: The associated component if this signal is an effect/computed */
 	ctx: null | ComponentContext;
 	/** destroy: Thing(s) that need destroying */
-	y: null | (() => void);
+	ondestroy: null | (() => void);
 	/** init: The function that we invoke for effects and computeds */
 	fn: null | (() => void | (() => void)) | ((b: Block, s: Signal) => void | (() => void));
 	/** value: The latest value for this signal, doubles as the teardown for effects */

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

@@ -1381,7 +1381,7 @@ export function bind_this(element_or_component, update, get_value, get_parts) {
 	// Add effect teardown (likely causes: if block became false, each item removed, component unmounted).
 	// In these cases we need to nullify the binding only if we detect that the value is still the same.
 	// If not, that means that another effect has now taken over the binding.
-	e.y = () => {
+	e.ondestroy = () => {
 		// Defer to the next tick so that all updates can be reconciled first.
 		// This solves the case where one variable is shared across multiple this-bindings.
 		effect(() => {
@@ -1552,7 +1552,7 @@ export function head(render_fn) {
 			block,
 			false
 		);
-		head_effect.y = () => {
+		head_effect.ondestroy = () => {
 			const current = block.d;
 			if (current !== null) {
 				remove(current);
@@ -1665,7 +1665,7 @@ export function element(anchor_node, tag_fn, is_svg, render_fn) {
 		block,
 		true
 	);
-	element_effect.y = () => {
+	element_effect.ondestroy = () => {
 		if (element !== null) {
 			remove(element);
 			block.d = null;
@@ -1778,7 +1778,7 @@ export function component(anchor_node, component_fn, render_fn) {
 		block,
 		false
 	);
-	component_effect.y = () => {
+	component_effect.ondestroy = () => {
 		let render = current_render;
 		while (render !== null) {
 			const dom = render.d;
@@ -1842,7 +1842,7 @@ export function css_props(anchor, is_html, props, component) {
 		}
 		current_props = next_props;
 	});
-	effect.y = () => {
+	effect.ondestroy = () => {
 		remove(tag);
 	};
 }
@@ -1874,7 +1874,7 @@ export function html(dom, get_value, svg) {
 			html_dom = reconcile_html(dom, value, svg);
 		}
 	});
-	effect.y = () => {
+	effect.ondestroy = () => {
 		if (html_dom) {
 			remove(html_dom);
 		}