.attachChild accept route from any constructor [fix]

lib/attach.js

@@ -7,16 +7,17 @@
 
 // Imports
 const Route = require('./index.js'),
-	{IS_INITIALIZED, ATTACH_TO, DEBUG_ZONE, DEBUG_ERROR} = require('./symbols.js');
+	{IS_INITIALIZED, ATTACH_TO, DEBUG_ZONE, DEBUG_ERROR} = require('./symbols.js'),
+	{isRoute} = Route;
 
 // Exports
 
 module.exports = {
 	attachChild(route) {
 		// Check is instance of Route class
-		if (!(route instanceof Route)) {
+		if (!isRoute(route)) {
 			throw this[DEBUG_ERROR](
-				new Error('attachChild must be called with an instance of Route class')
+				new Error(`attachChild must be called with an instance of Route class - received ${route}`)
 			);
 		}
 

test/attachChild.test.js

@@ -47,6 +47,28 @@ describe('.attachChild()', () => {
 		expect(child[ATTACH_TO]).toHaveBeenCalledWith(route);
 	});
 
+	describe('throws if passed', () => {
+		it('object', () => {
+			expect(() => route.attachChild({})).toThrowWithMessage(
+				Error,
+				'attachChild must be called with an instance of Route class - received [object Object] (router path /)'
+			);
+		});
+
+		it('Route class', () => { // eslint-disable-line jest/lowercase-name
+			expect(() => route.attachChild(Route)).toThrow(
+				/^attachChild must be called with an instance of Route class - received [\s\S]* \(router path \/\)$/
+			);
+		});
+
+		it('null', () => {
+			expect(() => route.attachChild(null)).toThrowWithMessage(
+				Error,
+				'attachChild must be called with an instance of Route class - received null (router path /)'
+			);
+		});
+	});
+
 	it('tags error thrown in `child[ATTACH_TO]()` with child router path', () => {
 		class RouteSubclass extends Route {
 			[ATTACH_TO](parent) {