[fix] handle arrow function on slot inside svelte:fragment (#7667)

Fixes #7485

src/compiler/compile/nodes/shared/Expression.ts

@@ -323,7 +323,7 @@ export default class Expression {
 
 							const func_expression = func_declaration[0];
 
-							if (node.type === 'InlineComponent') {
+							if (node.type === 'InlineComponent' || node.type === 'SlotTemplate') {
 								// <Comp let:data />
 								this.replace(func_expression);
 							} else {

test/runtime/samples/component-slot-let-inline-function/Inner.svelte

@@ -0,0 +1,8 @@
+<script>
+  export let log;
+  export let b;
+  function innerCall(a) {
+    log(`a: ${a}, b: ${b}`);
+  }
+</script>
+<slot name="inner_slot" {innerCall} />

test/runtime/samples/component-slot-let-inline-function/Outer.svelte

@@ -0,0 +1,12 @@
+<script>
+  import Inner from './Inner.svelte'
+  export let log;
+  export let a;
+	export let b;
+</script>
+
+<Inner {log} {b}>
+  <svelte:fragment let:innerCall slot="inner_slot">
+    <slot outerCall={() => innerCall(a)} />
+  </svelte:fragment>
+</Inner>

test/runtime/samples/component-slot-let-inline-function/_config.js

@@ -0,0 +1,27 @@
+let logs;
+function log(value) {
+	logs.push(value);
+}
+
+export default {
+	html: '<button>click me</button>',
+	props: {
+		a: 'a',
+		b: 'b',
+		log
+	},
+	before_test() {
+		logs = [];
+	},
+	async test({ assert, component, target, window }) {
+		const button = target.querySelector('button');
+		await button.dispatchEvent(new window.MouseEvent('click'));
+
+		assert.deepEqual(logs, ['a: a, b: b']);
+
+		component.a = '1'; 
+		component.b = '2';
+		await button.dispatchEvent(new window.MouseEvent('click'));
+		assert.deepEqual(logs, ['a: a, b: b', 'a: 1, b: 2']);
+	}
+};

test/runtime/samples/component-slot-let-inline-function/main.svelte

@@ -0,0 +1,12 @@
+<script>
+	import Outer from "./Outer.svelte";
+	export let log = [];
+	export let a;
+	export let b;
+</script>
+
+<Outer let:outerCall {log} {a} {b}>
+	<button on:click={outerCall}>
+		click me
+	</button>
+</Outer>