fix(router): Allow undefined inputs on routerLink (#39151)

This make it coherent with typing of Router.createUrlTree to which
those inputs are directly forwarded to. And hence it allow to pass
`undefined`, `null` or a value to the routerLink directive.

BREAKING CHANGE: in most cases this should not break, but if you were
accessing the values of `queryParams`, `fragment` or `queryParamsHandling`
you might need to relax the typing to also accept `undefined` and `null`.

Signed-off-by: Adrien Crivelli <adrien.crivelli@gmail.com>

PR Close #39151

goldens/public-api/router/router.d.ts

@@ -376,13 +376,11 @@ export declare class RouterEvent {
 }
 
 export declare class RouterLink implements OnChanges {
-    fragment: string;
+    fragment?: string;
     preserveFragment: boolean;
     /** @deprecated */ set preserveQueryParams(value: boolean);
-    queryParams: {
+    queryParams?: Params | null;
-        [k: string]: any;
+    queryParamsHandling?: QueryParamsHandling | null;
-    };
-    queryParamsHandling: QueryParamsHandling;
     replaceUrl: boolean;
     set routerLink(commands: any[] | string | null | undefined);
     skipLocationChange: boolean;
@@ -410,14 +408,12 @@ export declare class RouterLinkActive implements OnChanges, OnDestroy, AfterCont
 }
 
 export declare class RouterLinkWithHref implements OnChanges, OnDestroy {
-    fragment: string;
+    fragment?: string;
     href: string;
     preserveFragment: boolean;
     /** @deprecated */ set preserveQueryParams(value: boolean);
-    queryParams: {
+    queryParams?: Params | null;
-        [k: string]: any;
+    queryParamsHandling?: QueryParamsHandling | null;
-    };
-    queryParamsHandling: QueryParamsHandling;
     replaceUrl: boolean;
     set routerLink(commands: any[] | string | null | undefined);
     skipLocationChange: boolean;

packages/router/src/directives/router_link.ts

@@ -14,6 +14,7 @@ import {QueryParamsHandling} from '../config';
 import {Event, NavigationEnd} from '../events';
 import {Router} from '../router';
 import {ActivatedRoute} from '../router_state';
+import {Params} from '../shared';
 import {UrlTree} from '../url_tree';
 
 
@@ -122,24 +123,21 @@ export class RouterLink implements OnChanges {
    * @see {@link UrlCreationOptions#queryParams UrlCreationOptions#queryParams}
    * @see {@link Router#createUrlTree Router#createUrlTree}
    */
-  // TODO(issue/24571): remove '!'.
+  @Input() queryParams?: Params|null;
-  @Input() queryParams!: {[k: string]: any};
   /**
    * Passed to {@link Router#createUrlTree Router#createUrlTree} as part of the
    * `UrlCreationOptions`.
    * @see {@link UrlCreationOptions#fragment UrlCreationOptions#fragment}
    * @see {@link Router#createUrlTree Router#createUrlTree}
    */
-  // TODO(issue/24571): remove '!'.
+  @Input() fragment?: string;
-  @Input() fragment!: string;
   /**
    * Passed to {@link Router#createUrlTree Router#createUrlTree} as part of the
    * `UrlCreationOptions`.
    * @see {@link UrlCreationOptions#queryParamsHandling UrlCreationOptions#queryParamsHandling}
    * @see {@link Router#createUrlTree Router#createUrlTree}
    */
-  // TODO(issue/24571): remove '!'.
+  @Input() queryParamsHandling?: QueryParamsHandling|null;
-  @Input() queryParamsHandling!: QueryParamsHandling;
   /**
    * Passed to {@link Router#createUrlTree Router#createUrlTree} as part of the
    * `UrlCreationOptions`.
@@ -264,24 +262,21 @@ export class RouterLinkWithHref implements OnChanges, OnDestroy {
    * @see {@link UrlCreationOptions#queryParams UrlCreationOptions#queryParams}
    * @see {@link Router#createUrlTree Router#createUrlTree}
    */
-  // TODO(issue/24571): remove '!'.
+  @Input() queryParams?: Params|null;
-  @Input() queryParams!: {[k: string]: any};
   /**
    * Passed to {@link Router#createUrlTree Router#createUrlTree} as part of the
    * `UrlCreationOptions`.
    * @see {@link UrlCreationOptions#fragment UrlCreationOptions#fragment}
    * @see {@link Router#createUrlTree Router#createUrlTree}
    */
-  // TODO(issue/24571): remove '!'.
+  @Input() fragment?: string;
-  @Input() fragment!: string;
   /**
    * Passed to {@link Router#createUrlTree Router#createUrlTree} as part of the
    * `UrlCreationOptions`.
    * @see {@link UrlCreationOptions#queryParamsHandling UrlCreationOptions#queryParamsHandling}
    * @see {@link Router#createUrlTree Router#createUrlTree}
    */
-  // TODO(issue/24571): remove '!'.
+  @Input() queryParamsHandling?: QueryParamsHandling|null;
-  @Input() queryParamsHandling!: QueryParamsHandling;
   /**
    * Passed to {@link Router#createUrlTree Router#createUrlTree} as part of the
    * `UrlCreationOptions`.