prevent hanging with large numbers of links (#604)

test/apps/export/src/routes/boom/[a]/[b].svelte

@@ -0,0 +1,12 @@
+<script context="module">
+	export function preload({ params }) {
+		return params;
+	}
+</script>
+
+<script>
+	export let a;
+	export let b;
+</script>
+
+<p>{a}/{b}</p>

test/apps/export/src/routes/boom/[a]/index.svelte

@@ -0,0 +1,15 @@
+<script context="module">
+	export function preload({ params }) {
+		return params;
+	}
+</script>
+
+<script>
+	export let a;
+
+	const list = Array(20).fill().map((_, i) => i + 1);
+</script>
+
+{#each list as b}
+	<a href="boom/{a}/{b}">{a}/{b}</a>
+{/each}

test/apps/export/src/routes/boom/index.svelte

@@ -0,0 +1,7 @@
+<script>
+	const list = Array(20).fill().map((_, i) => i + 1);
+</script>
+
+{#each list as a}
+	<a href="boom/{a}">{a}</a>
+{/each}

test/apps/export/src/routes/index.svelte

@@ -7,3 +7,4 @@
 <a href= >empty anchor #4</a>
 <a href>empty anchor #5</a>
 <a>empty anchor #6</a>
+<a href="boom">boom</a>

test/apps/export/test.ts

@@ -19,7 +19,15 @@ describe('export', function() {
 
 		assert.ok(client_assets.length > 0);
 
-		assert.deepEqual(non_client_assets, [
+		const boom = ['boom/index.html'];
+		for (let a = 1; a <= 20; a += 1) {
+			boom.push(`boom/${a}/index.html`);
+			for (let b = 1; b <= 20; b += 1) {
+				boom.push(`boom/${a}/${b}/index.html`);
+			}
+		}
+
+		assert.deepEqual(non_client_assets.sort(), [
 			'blog.json',
 			'blog/bar.json',
 			'blog/bar/index.html',
@@ -31,8 +39,9 @@ describe('export', function() {
 			'global.css',
 			'index.html',
 			'service-worker-index.html',
-			'service-worker.js'
-		]);
+			'service-worker.js',
+			...boom
+		].sort());
 	});
 
 	// TODO test timeout, basepath