add a test which should pass without code change

src/compiler/compile/nodes/Element.ts

@@ -600,7 +600,7 @@ export default class Element extends Node {
 
 	validate_bindings_foreign() {
 		this.bindings
-			.filter(binding => binding.name !== 'this')
+			// .filter(binding => binding.name !== 'this')
 			.forEach(binding => {
 				this.component.error(binding, {
 					code: 'invalid-binding',

test/validator/index.ts

@@ -119,4 +119,17 @@ describe('validate', () => {
 			});
 		}, /Invalid namespace 'foriegn' \(did you mean 'foreign'\?\)/);
 	});
+
+	it('throws an error if \'this\' is bound for foreign element', () => {
+		assert.throws(() => {
+			svelte.compile(`
+			<script>
+				let whatever;
+			</script>
+			<div bind:this={whatever} />`, {
+				name: 'test',
+				namespace: 'foreign'
+			});
+		}, /'this' is not a valid binding/)
+	})
 });