fix: don't replace rest props with `$$props` for excluded props (#16898)

Closes #16895

.changeset/nervous-flies-laugh.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: don't replace rest props with `$$props` for excluded props

packages/svelte/src/compiler/phases/2-analyze/visitors/VariableDeclarator.js

@@ -46,6 +46,21 @@ export function VariableDeclarator(node, context) {
 								: path.is_rest
 									? 'rest_prop'
 									: 'prop';
+				if (rune === '$props' && binding.kind === 'rest_prop' && node.id.type === 'ObjectPattern') {
+					const { properties } = node.id;
+					/** @type {string[]} */
+					const exclude_props = [];
+					for (const property of properties) {
+						if (property.type === 'RestElement') {
+							continue;
+						}
+						const key = /** @type {Identifier | Literal & { value: string | number }} */ (
+							property.key
+						);
+						exclude_props.push(key.type === 'Identifier' ? key.name : key.value.toString());
+					}
+					(binding.metadata ??= {}).exclude_props = exclude_props;
+				}
 			}
 		}
 

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

@@ -32,7 +32,11 @@ export function Identifier(node, context) {
 				grand_parent?.type !== 'AssignmentExpression' &&
 				grand_parent?.type !== 'UpdateExpression'
 			) {
-				return b.id('$$props');
+				const key = /** @type {Identifier} */ (parent.property);
+
+				if (!binding.metadata?.exclude_props?.includes(key.name)) {
+					return b.id('$$props');
+				}
 			}
 		}
 

packages/svelte/src/compiler/phases/scope.js

@@ -122,7 +122,7 @@ export class Binding {
 
 	/**
 	 * Additional metadata, varies per binding type
-	 * @type {null | { inside_rest?: boolean; is_template_declaration?: boolean }}
+	 * @type {null | { inside_rest?: boolean; is_template_declaration?: boolean; exclude_props?: string[] }}
 	 */
 	metadata = null;
 

packages/svelte/tests/runtime-runes/samples/rest-props-excludes-properties/_config.js

@@ -0,0 +1,7 @@
+import { test } from '../../test';
+
+export default test({
+	async test({ assert, target }) {
+		assert.equal(target.textContent, ' false');
+	}
+});

packages/svelte/tests/runtime-runes/samples/rest-props-excludes-properties/component.svelte

@@ -0,0 +1,4 @@
+<script>
+    const { name, ...rest } = $props();
+</script>
+{rest.name} {'name' in rest}

packages/svelte/tests/runtime-runes/samples/rest-props-excludes-properties/main.svelte

@@ -0,0 +1,4 @@
+<script>
+    import Component from './component.svelte';
+</script>
+<Component name='world' />