fix some spread attribute stuff

packages/svelte/src/compiler/phases/1-parse/state/element.js

@@ -456,6 +456,7 @@ function read_attribute(parser) {
 				expression,
 				parent: null,
 				metadata: {
+					contains_call_expression: false,
 					dynamic: false
 				}
 			};

packages/svelte/src/compiler/phases/2-analyze/index.js

@@ -906,7 +906,10 @@ const common_visitors = {
 		}
 	},
 	CallExpression(node, context) {
-		if (context.state.expression?.type === 'ExpressionTag' && !is_known_safe_call(node, context)) {
+		if (
+			context.state.expression?.type === 'ExpressionTag' ||
+			(context.state.expression?.type === 'SpreadAttribute' && !is_known_safe_call(node, context))
+		) {
 			context.state.expression.metadata.contains_call_expression = true;
 		}
 

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

@@ -756,7 +756,20 @@ function serialize_inline_component(node, component_name, context) {
 			}
 			events[attribute.name].push(handler);
 		} else if (attribute.type === 'SpreadAttribute') {
-			props_and_spreads.push(/** @type {import('estree').Expression} */ (context.visit(attribute)));
+			const expression = /** @type {import('estree').Expression} */ (context.visit(attribute));
+			if (attribute.metadata.dynamic) {
+				let value = expression;
+
+				if (attribute.metadata.contains_call_expression) {
+					const id = b.id(context.state.scope.generate('spread_element'));
+					context.state.init.push(b.var(id, b.call('$.derived', b.thunk(value))));
+					value = b.call('$.get', id);
+				}
+
+				props_and_spreads.push(b.thunk(value));
+			} else {
+				props_and_spreads.push(expression);
+			}
 		} else if (attribute.type === 'Attribute') {
 			if (attribute.name.startsWith('--')) {
 				custom_css_props.push(
@@ -895,7 +908,7 @@ function serialize_inline_component(node, component_name, context) {
 			? b.object(/** @type {import('estree').Property[]} */ (props_and_spreads[0]) || [])
 			: b.call(
 					'$.spread_props',
-					...props_and_spreads.map((p) => (Array.isArray(p) ? b.object(p) : b.thunk(p)))
+					...props_and_spreads.map((p) => (Array.isArray(p) ? b.object(p) : p))
 			  );
 	/** @param {import('estree').Identifier} node_id */
 	let fn = (node_id) =>

packages/svelte/src/compiler/types/template.d.ts

@@ -434,6 +434,7 @@ export interface SpreadAttribute extends BaseNode {
 	type: 'SpreadAttribute';
 	expression: Expression;
 	metadata: {
+		contains_call_expression: boolean;
 		dynamic: boolean;
 	};
 }

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

@@ -2580,7 +2580,7 @@ const spread_props_handler = {
 		while (i--) {
 			let p = target.props[i];
 			if (typeof p === 'function') p = p();
-			if (key in p) return p[key];
+			if (typeof p === 'object' && p !== null && key in p) return p[key];
 		}
 	},
 	getOwnPropertyDescriptor() {