diff --git a/test/runtime/samples/dynamic-element-action-update/_config.js b/test/runtime/samples/dynamic-element-action-update/_config.js
index 3756313dab..c9d53088e9 100644
--- a/test/runtime/samples/dynamic-element-action-update/_config.js
+++ b/test/runtime/samples/dynamic-element-action-update/_config.js
@@ -1,27 +1,47 @@
+let logs = [];
+
 export default {
 	html: `
 		<h1>tag is h1.</h1>
 	`,
+	props: {
+		logs
+	},
+	before_test() {
+		logs = [];
+	},
 
 	async test({ assert, component, target }) {
-
 		assert.equal(component.tag, 'h1');
 		assert.equal(component.updateText, '');
 		assert.equal(component.destroyText, '');
 
+		assert.deepEqual(logs, ['create: h1,opt2']);
 		component.opt = 'opt2';
-		
+
 		assert.equal(component.tag, 'h1');
-		assert.equal(component.updateText, 'update: h1,opt2');
-		assert.equal(component.destroyText, '');
+		assert.deepEqual(logs, ['create: h1,opt2', 'update: h1,opt2']);
 
 		component.tag = 'h2';
 
 		assert.equal(component.tag, 'h2');
-		assert.equal(component.updateText, 'update: h1,opt2');
-		assert.equal(component.destroyText, 'destroy');
-		assert.htmlEqual(target.innerHTML, `
-			<h2>tag is h2.</h2>
-		`);
+		assert.deepEqual(logs, [
+			'create: h1,opt2',
+			'update: h1,opt2',
+			'destroy',
+			'create: h2,opt2'
+		]);
+		assert.htmlEqual(target.innerHTML, '<h2>tag is h2.</h2>');
+
+		component.tag = false;
+		assert.deepEqual(logs, [
+			'create: h1,opt2',
+			'update: h1,opt2',
+			'destroy',
+			'create: h2,opt2',
+			'destroy'
+		]);
+
+		assert.htmlEqual(target.innerHTML, '');
 	}
 };
diff --git a/test/runtime/samples/dynamic-element-action-update/main.svelte b/test/runtime/samples/dynamic-element-action-update/main.svelte
index beccf0071b..da269e115e 100644
--- a/test/runtime/samples/dynamic-element-action-update/main.svelte
+++ b/test/runtime/samples/dynamic-element-action-update/main.svelte
@@ -1,12 +1,12 @@
 <script>
-	export let updateText = "";
-	export let destroyText = "";
-  export let tag = "h1";
+  export let logs = [];
+	export let tag = "h1";
   export let opt = "opt1";
   function foo(node, {tag, opt}) {
+    logs.push(`create: ${tag},${opt}`);
     return {
-      update: ({tag, opt}) => updateText = `update: ${tag},${opt}`,
-      destroy: () => destroyText = 'destroy'
+      update: ({tag, opt}) => logs.push(`update: ${tag},${opt}`),
+      destroy: () => logs.push('destroy'),
     };
   }
 </script>
diff --git a/test/runtime/samples/dynamic-element-undefined-tag/_config.js b/test/runtime/samples/dynamic-element-undefined-tag/_config.js
index 22dc25b41e..53b4e6e563 100644
--- a/test/runtime/samples/dynamic-element-undefined-tag/_config.js
+++ b/test/runtime/samples/dynamic-element-undefined-tag/_config.js
@@ -1,3 +1,20 @@
 export default {
-	html: ''
+	solo: true,
+	html: '',
+	test({ component, target, assert }) {
+		component.tag = 'h1';
+		assert.htmlEqual(target.innerHTML, '<h1>Foo</h1>');
+
+		component.tag = null;
+		assert.htmlEqual(target.innerHTML, '');
+
+		component.tag = 'div';
+		assert.htmlEqual(target.innerHTML, '<div>Foo</div>');
+
+		component.tag = false;
+		assert.htmlEqual(target.innerHTML, '');
+
+		component.tag = 'span';
+		assert.htmlEqual(target.innerHTML, '<span>Foo</span>');
+	}
 };
diff --git a/test/runtime/samples/dynamic-element-undefined-tag/main.svelte b/test/runtime/samples/dynamic-element-undefined-tag/main.svelte
index 785ab58073..6aca93ca13 100644
--- a/test/runtime/samples/dynamic-element-undefined-tag/main.svelte
+++ b/test/runtime/samples/dynamic-element-undefined-tag/main.svelte
@@ -1,5 +1,5 @@
 <script>
-  let tag;
+  export let tag;
 </script>
 
 <svelte:element this={tag}>Foo</svelte:element>