refactor(router): code cleanup

modules/@angular/common/src/location/location.ts

@@ -96,7 +96,7 @@ export class Location {
    * used, or the `APP_BASE_HREF` if the `PathLocationStrategy` is in use.
    */
   prepareExternalUrl(url: string): string {
-    if (url.length > 0 && !url.startsWith('/')) {
+    if (url && url[0] !== '/') {
       url = '/' + url;
     }
     return this._platformStrategy.prepareExternalUrl(url);
@@ -143,7 +143,7 @@ export class Location {
    * is.
    */
   public static normalizeQueryParams(params: string): string {
-    return (params.length > 0 && params.substring(0, 1) != '?') ? ('?' + params) : params;
+    return params && params[0] !== '?' ? '?' + params : params;
   }
 
   /**
@@ -175,25 +175,13 @@ export class Location {
   /**
    * If url has a trailing slash, remove it, otherwise return url as is.
    */
-  public static stripTrailingSlash(url: string): string {
-    if (/\/$/g.test(url)) {
-      url = url.substring(0, url.length - 1);
-    }
-    return url;
-  }
+  public static stripTrailingSlash(url: string): string { return url.replace(/\/$/, ''); }
 }
 
 function _stripBaseHref(baseHref: string, url: string): string {
-  if (baseHref.length > 0 && url.startsWith(baseHref)) {
-    return url.substring(baseHref.length);
-  }
-  return url;
+  return baseHref && url.startsWith(baseHref) ? url.substring(baseHref.length) : url;
 }
 
 function _stripIndexHtml(url: string): string {
-  if (/\/index.html$/g.test(url)) {
-    // '/index.html'.length == 11
-    return url.substring(0, url.length - 11);
-  }
-  return url;
+  return url.replace(/\/index.html$/, '');
 }

modules/@angular/router/src/router.ts

@@ -23,7 +23,7 @@ import {mergeMap} from 'rxjs/operator/mergeMap';
 import {reduce} from 'rxjs/operator/reduce';
 
 import {applyRedirects} from './apply_redirects';
-import {Data, ResolveData, Routes, validateConfig} from './config';
+import {ResolveData, Routes, validateConfig} from './config';
 import {createRouterState} from './create_router_state';
 import {createUrlTree} from './create_url_tree';
 import {RouterOutlet} from './directives/router_outlet';
@@ -38,7 +38,7 @@ import {UrlSerializer, UrlTree, containsTree, createEmptyUrlTree} from './url_tr
 import {andObservables, forEach, merge, waitForMap, wrapIntoObservable} from './utils/collection';
 import {TreeNode} from './utils/tree';
 
-declare var Zone: any;
+declare let Zone: any;
 
 /**
  * @whatItDoes Represents the extra options used during navigation.
@@ -55,16 +55,13 @@ export interface NavigationExtras {
   * [{
   *   path: 'parent',
   *   component: ParentComponent,
-  *   children: [
-  *     {
+  *   children: [{
   *     path: 'list',
   *     component: ListComponent
-  *     },
-  *     {
+  *   },{
   *     path: 'child',
   *     component: ChildComponent
-  *     }
-  *   ]
+  *   }]
   * }]
   * ```
   *