use proxies instead of signals for spread/rest

packages/svelte/src/compiler/phases/3-transform/client/utils.js

@@ -88,7 +88,6 @@ export function serialize_get_binding(node, state) {
 			(!state.analysis.immutable || state.analysis.accessors || binding.reassigned)) ||
 		binding.kind === 'derived' ||
 		binding.kind === 'prop' ||
-		binding.kind === 'rest_prop' ||
 		binding.kind === 'legacy_reactive'
 	) {
 		return b.call('$.get', node);

packages/svelte/src/compiler/phases/3-transform/client/visitors/global.js

@@ -7,7 +7,7 @@ export const global_visitors = {
 	Identifier(node, { path, state }) {
 		if (is_reference(node, /** @type {import('estree').Node} */ (path.at(-1)))) {
 			if (node.name === '$$props') {
-				return b.call('$.get', b.id('$$sanitized_props'));
+				return b.id('$$sanitized_props');
 			}
 			return serialize_get_binding(node, state);
 		}

packages/svelte/src/compiler/phases/3-transform/client/visitors/template.js

@@ -895,7 +895,7 @@ function serialize_inline_component(node, component_name, context) {
 			? b.object(/** @type {import('estree').Property[]} */ (props_and_spreads[0]) || [])
 			: b.call(
 					'$.spread_props',
-					b.thunk(b.array(props_and_spreads.map((p) => (Array.isArray(p) ? b.object(p) : p))))
+					...props_and_spreads.map((p) => (Array.isArray(p) ? b.object(p) : b.thunk(p)))
 			  );
 	/** @param {import('estree').Identifier} node_id */
 	let fn = (node_id) =>
@@ -2854,7 +2854,9 @@ export const template_visitors = {
 
 		for (const attribute of node.attributes) {
 			if (attribute.type === 'SpreadAttribute') {
-				spreads.push(/** @type {import('estree').Expression} */ (context.visit(attribute)));
+				spreads.push(
+					b.thunk(/** @type {import('estree').Expression} */ (context.visit(attribute)))
+				);
 			} else if (attribute.type === 'Attribute') {
 				const [, value] = serialize_attribute_value(attribute.value, context);
 				if (attribute.name === 'name') {
@@ -2873,7 +2875,7 @@ export const template_visitors = {
 		const props_expression =
 			spreads.length === 0
 				? b.object(props)
-				: b.call('$.spread_props', b.thunk(b.array([b.object(props), ...spreads])));
+				: b.call('$.spread_props', b.object(props), ...spreads);
 		const fallback =
 			node.fragment.nodes.length === 0
 				? b.literal(null)

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

@@ -2528,71 +2528,93 @@ export function spread_dynamic_element_attributes(node, prev, attrs, css_hash) {
 }
 
 /**
- * @param {import('./types.js').Signal<Record<string, unknown>> | Record<string, unknown>} props_signal
- * @param {string[]} rest
- * @returns {Record<string, unknown>}
+ * @type {ProxyHandler<{ props: Record<string | symbol, unknown>, exclude: Array<string | symbol> }>}}
  */
-export function rest_props(props_signal, rest) {
-	return derived(() => {
-		var props = unwrap(props_signal);
-
-		observe(props);
-
-		/** @type {Record<string, unknown>} */
-		var rest_props = {};
-
-		for (const key in props) {
-			if (rest.includes(key)) continue;
+const rest_props_handler = {
+	get(target, key) {
+		if (target.exclude.includes(key)) return;
+		return target.props[key];
+	},
+	getOwnPropertyDescriptor(target, key) {
+		if (target.exclude.includes(key)) return;
+		if (key in target.props) {
+			return {
+				enumerable: true,
+				configurable: true,
+				value: target.props[key]
+			};
+		}
+	},
+	has(target, key) {
+		if (target.exclude.includes(key)) return false;
+		return key in target.props;
+	},
+	ownKeys(target) {
+		/** @type {Array<string | symbol>} */
+		const keys = [];
 
-			const { enumerable } = /** @type {PropertyDescriptor} */ (get_descriptor(props, key));
+		for (let key in target.props) {
+			if (!target.exclude.includes(key)) keys.push(key);
+		}
 
-			define_property(rest_props, key, {
-				get: () => props[key],
-				enumerable
-			});
+		return keys;
 	}
+};
 
-		return rest_props;
-	});
+/**
+ * @param {import('./types.js').Signal<Record<string, unknown>> | Record<string, unknown>} props
+ * @param {string[]} rest
+ * @returns {Record<string, unknown>}
+ */
+export function rest_props(props, rest) {
+	return new Proxy({ props, exclude: rest }, rest_props_handler);
 }
 
 /**
- * @param {Record<string, unknown>[] | (() => Record<string, unknown>[])} props
- * @returns {any}
+ * @template {Record<string | symbol, unknown>} T
+ * @type {ProxyHandler<{ props: Array<T | (() => T)> }>}}
  */
-export function spread_props(props) {
-	if (typeof props === 'function') {
-		return derived(() => {
-			return spread_props(props());
-		});
+const spread_props_handler = {
+	get(target, key) {
+		let i = target.props.length;
+		while (i--) {
+			let p = target.props[i];
+			if (typeof p === 'function') p = p();
+			if (key in p) return p[key];
+		}
+	},
+	getOwnPropertyDescriptor() {
+		return { enumerable: true, configurable: true };
+	},
+	has(target, key) {
+		for (let p of target.props) {
+			if (typeof p === 'function') p = p();
+			if (key in p) return true;
 		}
 
-	/** @type {Record<string, unknown>} */
-	const merged_props = {};
-	let key;
-	for (let i = 0; i < props.length; i++) {
-		const obj = props[i];
-		for (key in obj) {
-			const desc = /** @type {PropertyDescriptor} */ (get_descriptor(obj, key));
-			const getter = desc.get;
-			if (getter !== undefined) {
-				define_property(merged_props, key, {
-					enumerable: true,
-					configurable: true,
-					get: getter
-				});
-			} else if (desc.get !== undefined) {
-				merged_props[key] = obj[key];
-			} else {
-				define_property(merged_props, key, {
-					enumerable: true,
-					configurable: true,
-					value: obj[key]
-				});
+		return false;
+	},
+	ownKeys(target) {
+		/** @type {Array<string | symbol>} */
+		const keys = [];
+
+		for (let p of target.props) {
+			if (typeof p === 'function') p = p();
+			for (const key in p) {
+				if (!keys.includes(key)) keys.push(key);
 			}
 		}
+
+		return keys;
 	}
-	return merged_props;
+};
+
+/**
+ * @param {Array<Record<string, unknown> | (() => Record<string, unknown>)>} props
+ * @returns {any}
+ */
+export function spread_props(...props) {
+	return new Proxy({ props }, spread_props_handler);
 }
 
 /**

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

@@ -1426,6 +1426,10 @@ export function prop_source(props_obj, key, flags, default_value) {
 	const immutable = (flags & PROPS_IS_IMMUTABLE) !== 0;
 	const runes = (flags & PROPS_IS_RUNES) !== 0;
 
+	if (is_signal(props_obj)) {
+		// throw new Error('nope');
+	}
+
 	const props = is_signal(props_obj) ? get(props_obj) : props_obj;
 	const update_bound_prop = get_descriptor(props, key)?.set;
 	let value = props[key];