Add Svelte as a syntax

tests/syntax-tests/source/Svelte/App.svelte

@@ -0,0 +1,57 @@
+<script>
+	import { onMount } from 'svelte';
+	import List from './List.svelte';
+	import Item from './Item.svelte';
+
+	let item;
+	let page;
+
+	async function hashchange() {
+		// the poor man's router!
+		const path = window.location.hash.slice(1);
+
+		if (path.startsWith('/item')) {
+			const id = path.slice(6);
+			item = await fetch(`https://node-hnapi.herokuapp.com/item/${id}`).then(r => r.json());
+
+			window.scrollTo(0,0);
+		} else if (path.startsWith('/top')) {
+			page = +path.slice(5);
+			item = null;
+		} else {
+			window.location.hash = '/top/1';
+		}
+	}
+
+	onMount(hashchange);
+</script>
+
+<style>
+	main {
+		position: relative;
+		max-width: 800px;
+		margin: 0 auto;
+		min-height: 101vh;
+		padding: 1em;
+	}
+
+	main :global(.meta) {
+		color: #999;
+		font-size: 12px;
+		margin: 0 0 1em 0;
+	}
+
+	main :global(a) {
+		color: rgb(0,0,150);
+	}
+</style>
+
+<svelte:window on:hashchange={hashchange}/>
+
+<main>
+	{#if item}
+		<Item {item} returnTo="#/top/{page}"/>
+	{:else if page}
+		<List {page}/>
+	{/if}
+</main>