chore: fix `$props.id` tests (#15294)

* chore: fix `$props.id` tests

* chore: reset uid between tests

packages/svelte/src/internal/client/dom/template.js

@@ -252,6 +252,10 @@ export function append(anchor, dom) {
 
 let uid = 1;
 
+export function reset_props_id() {
+	uid = 1;
+}
+
 /**
  * Create (or hydrate) an unique UID for the component instance.
  */

packages/svelte/tests/runtime-legacy/shared.ts

@@ -11,6 +11,7 @@ import { setup_html_equal } from '../html_equal.js';
 import { raf } from '../animation-helpers.js';
 import type { CompileOptions } from '#compiler';
 import { suite_with_variants, type BaseTest } from '../suite.js';
+import { reset_props_id } from '../../src/internal/client/dom/template.js';
 
 type Assert = typeof import('vitest').assert & {
 	htmlEqual(a: string, b: string, description?: string): void;
@@ -345,6 +346,7 @@ async function run_test_variant(
 
 			if (runes) {
 				props = proxy({ ...(config.props || {}) });
+				reset_props_id();
 				if (manual_hydrate) {
 					hydrate_fn = () => {
 						instance = hydrate(mod.default, {

packages/svelte/tests/runtime-runes/samples/props-id/_config.js

@@ -43,8 +43,6 @@ export default test({
 				`
 			);
 		} else {
-			// `c6` because this runs after the `dom` tests
-			// (slightly brittle but good enough for now)
 			assert.htmlEqual(
 				target.innerHTML,
 				`
@@ -53,7 +51,7 @@ export default test({
 					<p>s2</p>
 					<p>s3</p>
 					<p>s4</p>
-					<p>c6</p>
+					<p>c1</p>
 				`
 			);
 		}