fix a bug

src/compiler/compile/Component.ts

@@ -796,21 +796,23 @@ export default class Component {
 				let deep = false;
 				let names: string[] = [];
 
-				if (node.type === 'AssignmentExpression' &&
+				if (node.type === 'AssignmentExpression') {
-					node.left.type === 'ArrayPattern') {
+					if (node.left.type === 'ArrayPattern') {
 						walk(node.left, {
 							enter(node: Node, parent: Node) {
 								if (node.type === 'Identifier' &&
-								parent.type !== 'MemberExpression') {
+									parent.type !== 'MemberExpression' &&
+									(parent.type !== "AssignmentPattern" || parent.right !== node)) {
 										names.push(node.name);
 								}
 							}
 						});
-				} else if (node.type === 'AssignmentExpression') {
+					} else {
 						deep = node.left.type === 'MemberExpression';
 						names = deep
 							? [get_object(node.left).name]
 							: extract_names(node.left);
+					}
 				} else if (node.type === 'UpdateExpression') {
 					deep = node.argument.type === 'MemberExpression';
 					const { name } = get_object(node.argument);