add test, tweak codegen

src/compile/nodes/Component.ts

@@ -155,7 +155,7 @@ export default class Component extends Node {
 			componentInitProperties.push(`data: ${name_initial_data}`);
 		}
 
-		if ((!usesSpread && this.attributes.filter(a => a.isDynamic).length) || this.bindings.length) {
+		if (!usesSpread && (this.attributes.filter(a => a.isDynamic).length || this.bindings.length)) {
 			updates.push(`var ${name_changes} = {};`);
 		}
 
@@ -209,7 +209,7 @@ export default class Component extends Node {
 				updates.push(deindent`
 					var ${name_changes} = ${allDependencies.size === 1 ? `${conditions}` : `(${conditions})`} ? @getSpreadUpdate(${levels}, [
 						${changes.join(',\n')}
-					]) : ${name_changes};
+					]) : {};
 				`);
 			} else {
 				this.attributes

test/runtime/samples/spread-component-with-bind/Widget.html

@@ -0,0 +1,2 @@
+<p>{value}</p>
+<input bind:value/>

test/runtime/samples/spread-component-with-bind/_config.js

@@ -0,0 +1,18 @@
+export default {
+	html: `
+		<p>foo</p>
+		<input>
+	`,
+
+	test (assert, component, target, window) {
+		const input = target.querySelector('input');
+
+		input.value = 'bar';
+		input.dispatchEvent(new window.Event('input'));
+
+		assert.htmlEqual(target.innerHTML, `
+			<p>bar</p>
+			<input>
+		`);
+	}
+};

test/runtime/samples/spread-component-with-bind/main.html

@@ -0,0 +1,15 @@
+<svelte:component this={Widget} {...props} bind:value="x" />
+
+<script>
+	import Widget from './Widget.html';
+
+	export default {
+		data() {
+			return {
+				Widget,
+				x: 'foo',
+				props: {}
+			}
+		}
+	};
+</script>