refactor(router): Use NavigationTrigger more consistently and move events helper next to definitions (angular#60736)

This adjusts code to use `NavigationTrigger` type where appropriate and moves the `isPublicRouterEvent` next to the private event type union to make it more obvious that it should be updated along with any updates to the private type union. PR Close angular#60736

Author: atscott

goldens/public-api/router/index.api.md

@@ -408,7 +408,7 @@ export interface Navigation {
  id: number;
  initialUrl: UrlTree;
  previousNavigation: Navigation | null;
- trigger: 'imperative' | 'popstate' | 'hashchange';
+ trigger: NavigationTrigger;
 }
 
 // @public

packages/router/src/events.ts

@@ -624,6 +624,9 @@ export class RedirectRequest {
  ) {}
 }
 export type PrivateRouterEvents = BeforeActivateRoutes | RedirectRequest;
+export function isPublicRouterEvent(e: Event | PrivateRouterEvents): e is Event {
+ return !(e instanceof BeforeActivateRoutes) && !(e instanceof RedirectRequest);
+}
 
 /**
  * Router events that allow you to track the lifecycle of the router.

packages/router/src/navigation_transition.ts

@@ -281,12 +281,8 @@ export interface Navigation {
  targetRouterState?: RouterState;
  /**
  * Identifies how this navigation was triggered.
- *
- * * 'imperative'--Triggered by `router.navigateByUrl` or `router.navigate`.
- * * 'popstate'--Triggered by a popstate event.
- * * 'hashchange'--Triggered by a hashchange event.
  */
- trigger: 'imperative' | 'popstate' | 'hashchange';
+ trigger: NavigationTrigger;
  /**
  * Options that controlled the strategy used for this navigation.
  * See `NavigationExtras`.

packages/router/src/router.ts

@@ -23,14 +23,13 @@ import {createSegmentGroupFromRoute, createUrlTreeFromSegmentGroup} from './crea
 import {INPUT_BINDER} from './directives/router_outlet';
 import {RuntimeErrorCode} from './errors';
 import {
- BeforeActivateRoutes,
  Event,
  IMPERATIVE_NAVIGATION,
+ isPublicRouterEvent,
  NavigationCancel,
  NavigationCancellationCode,
  NavigationEnd,
  NavigationTrigger,
- PrivateRouterEvents,
  RedirectRequest,
 } from './events';
 import {NavigationBehaviorOptions, OnSameUrlNavigation, Routes} from './models';
@@ -686,7 +685,3 @@ function validateCommands(commands: string[]): void {
  }
  }
 }
-
-function isPublicRouterEvent(e: Event | PrivateRouterEvents): e is Event {
- return !(e instanceof BeforeActivateRoutes) && !(e instanceof RedirectRequest);
-}

packages/router/src/router_scroller.ts

@@ -7,21 +7,16 @@
  */
 
 import {ViewportScroller} from '@angular/common';
-import {
- EnvironmentInjector,
- inject,
- Injectable,
- InjectionToken,
- NgZone,
- OnDestroy,
-} from '@angular/core';
+import {Injectable, InjectionToken, NgZone, OnDestroy} from '@angular/core';
 import {Unsubscribable} from 'rxjs';
 
 import {
+ IMPERATIVE_NAVIGATION,
  NavigationEnd,
  NavigationSkipped,
  NavigationSkippedCode,
  NavigationStart,
+ NavigationTrigger,
  Scroll,
 } from './events';
 import {NavigationTransitions} from './navigation_transition';
@@ -35,7 +30,7 @@ export class RouterScroller implements OnDestroy {
  private scrollEventsSubscription?: Unsubscribable;
 
  private lastId = 0;
- private lastSource: 'imperative' | 'popstate' | 'hashchange' | undefined = 'imperative';
+ private lastSource: NavigationTrigger | undefined = IMPERATIVE_NAVIGATION;
  private restoredId = 0;
  private store: {[key: string]: [number, number]} = {};