fix const declared without let: binding get ignored (#7434)

src/compiler/compile/nodes/SlotTemplate.ts

@@ -27,10 +27,7 @@ export default class SlotTemplate extends Node {
 
 		this.validate_slot_template_placement();
 
-		const has_let = info.attributes.some((node) => node.type === 'Let');
-		if (has_let) {
-			scope = scope.child();
-		}
+		scope = scope.child();
 
 		info.attributes.forEach((node) => {
 			switch (node.type) {

test/runtime/samples/const-tag-component-without-let/Component.svelte

@@ -0,0 +1,2 @@
+<slot name="box1" />
+<slot />

test/runtime/samples/const-tag-component-without-let/_config.js

@@ -0,0 +1,15 @@
+export default {
+	html: `
+		<div>static dynamic</div>
+		<div>static dynamic</div>
+		<div>static dynamic</div>
+	`,
+	async test({ component, target, assert }) {
+		component.props = 'xxx';
+		assert.htmlEqual(target.innerHTML, `
+			<div>static xxx</div>
+			<div>static xxx</div>
+			<div>static xxx</div>
+		`);
+	}
+};

test/runtime/samples/const-tag-component-without-let/main.svelte

@@ -0,0 +1,24 @@
+<script>
+	import Component from './Component.svelte';
+	export let props = "dynamic";
+</script>
+
+<Component>
+	<svelte:fragment slot="box1">
+		{@const foo = "static"}
+		{@const bar = props}
+		<div>{foo} {bar}</div>
+	</svelte:fragment>
+
+	<svelte:fragment>
+		{@const foo = "static"}
+		{@const bar = props}
+		<div>{foo} {bar}</div>
+	</svelte:fragment>
+</Component>
+
+<Component>
+	{@const foo = "static"}
+	{@const bar = props}
+	<div>{foo} {bar}</div>
+</Component>