From d3eda7a5b5662e4bb01ea5ec5dd981eea3fbef04 Mon Sep 17 00:00:00 2001
From: Victor Berchet <victor@suumit.com>
Date: Mon, 20 Mar 2017 09:19:25 -0700
Subject: [PATCH] feat(router): add `ParamMap.keys` to get a list of parameters

---
 packages/router/src/index.ts              |  2 +-
 packages/router/src/shared.ts             | 10 ++++++++++
 packages/router/test/shared.spec.ts       |  5 +++++
 tools/public_api_guard/router/router.d.ts |  4 ++++
 4 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/packages/router/src/index.ts b/packages/router/src/index.ts
index d21e6151d9..6e329cf2be 100644
--- a/packages/router/src/index.ts
+++ b/packages/router/src/index.ts
@@ -20,7 +20,7 @@ export {ExtraOptions, ROUTER_CONFIGURATION, ROUTER_INITIALIZER, RouterModule, pr
 export {RouterOutletMap} from './router_outlet_map';
 export {NoPreloading, PreloadAllModules, PreloadingStrategy, RouterPreloader} from './router_preloader';
 export {ActivatedRoute, ActivatedRouteSnapshot, RouterState, RouterStateSnapshot} from './router_state';
-export {PRIMARY_OUTLET, ParamMap, Params} from './shared';
+export {PRIMARY_OUTLET, ParamMap, Params, convertToParamMap} from './shared';
 export {UrlHandlingStrategy} from './url_handling_strategy';
 export {DefaultUrlSerializer, UrlSegment, UrlSegmentGroup, UrlSerializer, UrlTree} from './url_tree';
 export {VERSION} from './version';
diff --git a/packages/router/src/shared.ts b/packages/router/src/shared.ts
index 7f2efba140..1ca5dfbcf6 100644
--- a/packages/router/src/shared.ts
+++ b/packages/router/src/shared.ts
@@ -54,6 +54,9 @@ export interface ParamMap {
    * If there is no such parameter, an empty array is returned.
    */
   getAll(name: string): string[];
+
+  /** Name of the parameters */
+  readonly keys: string[];
 }
 
 class ParamsAsMap implements ParamMap {
@@ -80,8 +83,15 @@ class ParamsAsMap implements ParamMap {
 
     return [];
   }
+
+  get keys(): string[] { return Object.keys(this.params); }
 }
 
+/**
+ * Convert a {@link Params} instance to a {@link ParamMap}.
+ *
+ * @stable
+ */
 export function convertToParamMap(params: Params): ParamMap {
   return new ParamsAsMap(params);
 }
diff --git a/packages/router/test/shared.spec.ts b/packages/router/test/shared.spec.ts
index 3e2edfed09..605782eb72 100644
--- a/packages/router/test/shared.spec.ts
+++ b/packages/router/test/shared.spec.ts
@@ -16,6 +16,11 @@ describe('ParamsMap', () => {
     expect(map.has('not here')).toEqual(false);
   });
 
+  it('should returns the name of the parameters', () => {
+    const map = convertToParamMap({single: 's', multiple: ['m1', 'm2']});
+    expect(map.keys).toEqual(['single', 'multiple']);
+  });
+
   it('should support single valued parameters', () => {
     const map = convertToParamMap({single: 's', multiple: ['m1', 'm2']});
     expect(map.get('single')).toEqual('s');
diff --git a/tools/public_api_guard/router/router.d.ts b/tools/public_api_guard/router/router.d.ts
index 42a53a6f06..80b574e659 100644
--- a/tools/public_api_guard/router/router.d.ts
+++ b/tools/public_api_guard/router/router.d.ts
@@ -59,6 +59,9 @@ export interface CanLoad {
     canLoad(route: Route): Observable<boolean> | Promise<boolean> | boolean;
 }
 
+/** @stable */
+export declare function convertToParamMap(params: Params): ParamMap;
+
 /** @stable */
 export declare type Data = {
     [name: string]: any;
@@ -156,6 +159,7 @@ export declare class NoPreloading implements PreloadingStrategy {
 
 /** @stable */
 export interface ParamMap {
+    readonly keys: string[];
     get(name: string): string | null;
     getAll(name: string): string[];
     has(name: string): boolean;