fix: make sure returned elements are not primitives

packages/svelte/src/internal/client/custom-renderer/index.js

@@ -3,10 +3,10 @@ import { branch, effect_root } from '../reactivity/effects.js';
 import { push_renderer } from './state.js';
 
 /**
- * @template [TFragment=any]
- * @template [TElement=any]
- * @template [TTextNode=any]
- * @template [TComment=any]
+ * @template {object} [TFragment=object]
+ * @template {object} [TElement=object]
+ * @template {object} [TTextNode=object]
+ * @template {object} [TComment=object]
  * @template [TNode=TFragment | TElement | TTextNode | TComment]
  * @typedef {Object} Renderer
  * @property {()=>TFragment} createFragment - Creates a fragment, a container for multiple nodes. Inserting a fragment should insert all of it's children.
@@ -31,10 +31,10 @@ import { push_renderer } from './state.js';
  */
 
 /**
- * @template [TFragment=unknown]
- * @template [TElement=unknown]
- * @template [TTextNode=unknown]
- * @template [TComment=unknown]
+ * @template {object} [TFragment=object]
+ * @template {object} [TElement=object]
+ * @template {object} [TTextNode=object]
+ * @template {object} [TComment=object]
  * @param {Renderer<TFragment, TElement, TTextNode, TComment>} renderer
  * @returns {Renderer<TFragment, TElement, TTextNode, TComment> & { render: (Component: any, options: { target: TFragment | TElement | TTextNode | TComment, props?: any }) => () => void }}
  */

packages/svelte/src/internal/client/custom-renderer/state.js

@@ -3,12 +3,12 @@
  */
 
 /**
- * @type {Renderer | null}
+ * @type {Renderer<any, any, any, any> | null}
  */
 export let renderer = null;
 
 /**
- * @param {Renderer | null} $renderer
+ * @param {Renderer<any, any, any, any> | null} $renderer
  */
 export function set_renderer($renderer) {
 	renderer = $renderer;
@@ -16,7 +16,7 @@ export function set_renderer($renderer) {
 
 /**
  *
- * @param {Renderer} $renderer
+ * @param {Renderer<any, any, any, any>} $renderer
  */
 export function push_renderer($renderer) {
 	let old_renderer = renderer;

packages/svelte/src/internal/client/dev/elements.js

@@ -34,7 +34,6 @@ export function add_locations(fn, filename, locations) {
  */
 function assign_location(element, filename, location) {
 	// @ts-expect-error
-	// TODO RENDERER: what if the element is not an object?
 	element.__svelte_meta = {
 		parent: dev_stack,
 		loc: { file: filename, line: location[0], column: location[1] }

packages/svelte/types/index.d.ts

@@ -2568,13 +2568,13 @@ declare module 'svelte/reactivity/window' {
 }
 
 declare module 'svelte/renderer' {
-	export function createRenderer<TFragment = unknown, TElement = unknown, TTextNode = unknown, TComment = unknown>(renderer: Renderer<TFragment, TElement, TTextNode, TComment>): Renderer<TFragment, TElement, TTextNode, TComment> & {
+	export function createRenderer<TFragment extends object = object, TElement extends object = object, TTextNode extends object = object, TComment extends object = object>(renderer: Renderer<TFragment, TElement, TTextNode, TComment>): Renderer<TFragment, TElement, TTextNode, TComment> & {
 		render: (Component: any, options: {
 			target: TFragment | TElement | TTextNode | TComment;
 			props?: any;
 		}) => () => void;
 	};
-	export type Renderer<TFragment = any, TElement = any, TTextNode = any, TComment = any, TNode = TFragment | TElement | TTextNode | TComment> = {
+	export type Renderer<TFragment extends object = object, TElement extends object = object, TTextNode extends object = object, TComment extends object = object, TNode = TFragment | TElement | TTextNode | TComment> = {
 		/**
 		 * - Creates a fragment, a container for multiple nodes. Inserting a fragment should insert all of it's children.
 		 */