fix(router): revert commit that replaced last helper with native Array.at(-1) (#54021)

atscott · pkozlowski-opensource · commit bc85551bfce7 · 2024-01-24T10:54:52.000+01:00
While `Array.at` is technically supported in all browsers we officially support, the change was needlessly breaking without any real benefit. PR Close #54021
diff --git a/packages/core/test/bundling/router/bundle.golden_symbols.json b/packages/core/test/bundling/router/bundle.golden_symbols.json
@@ -1583,6 +1583,9 @@
   {
     "name": "last"
   },
+  {
+    "name": "last3"
+  },
   {
     "name": "lastNodeWasCreated"
   },
diff --git a/packages/router/src/create_url_tree.ts b/packages/router/src/create_url_tree.ts
@@ -12,7 +12,7 @@ import {RuntimeErrorCode} from './errors';
 import {ActivatedRouteSnapshot} from './router_state';
 import {Params, PRIMARY_OUTLET} from './shared';
 import {createRoot, squashSegmentGroup, UrlSegment, UrlSegmentGroup, UrlTree} from './url_tree';
-import {shallowEqual} from './utils/collection';
+import {last, shallowEqual} from './utils/collection';
 
 
 /**
@@ -187,7 +187,7 @@ class Navigation {
     }
 
     const cmdWithOutlet = commands.find(isCommandWithOutlets);
-    if (cmdWithOutlet && cmdWithOutlet !== commands.at(-1)) {
+    if (cmdWithOutlet && cmdWithOutlet !== last(commands)) {
       throw new RuntimeError(
           RuntimeErrorCode.MISPLACED_OUTLETS_COMMAND,
           (typeof ngDevMode === 'undefined' || ngDevMode) &&
diff --git a/packages/router/src/utils/collection.ts b/packages/router/src/utils/collection.ts
@@ -57,6 +57,13 @@ export function equalArraysOrString(a: string|string[], b: string|string[]) {
   }
 }
 
+/**
+ * Return the last element of an array.
+ */
+export function last<T>(a: T[]): T|null {
+  return a.length > 0 ? a[a.length - 1] : null;
+}
+
 export function wrapIntoObservable<T>(value: T|Promise<T>|Observable<T>): Observable<T> {
   if (isObservable(value)) {
     return value;
diff --git a/packages/router/src/utils/config_matching.ts b/packages/router/src/utils/config_matching.ts
@@ -15,6 +15,7 @@ import {runCanMatchGuards} from '../operators/check_guards';
 import {defaultUrlMatcher, PRIMARY_OUTLET} from '../shared';
 import {UrlSegment, UrlSegmentGroup, UrlSerializer} from '../url_tree';
 
+import {last} from './collection';
 import {getOrCreateRouteInjectorIfNeeded, getOutlet} from './config';
 
 export interface MatchResult {
@@ -95,7 +96,7 @@ export function match(
 function createWildcardMatchResult(segments: UrlSegment[]): MatchResult {
   return {
     matched: true,
-    parameters: segments.at(-1)?.parameters ?? {},
+    parameters: segments.length > 0 ? last(segments)!.parameters : {},
     consumedSegments: segments,
     remainingSegments: [],
     positionalParamSegments: {},

Original file line number	Diff line number	Diff line change
`@@ -1583,6 +1583,9 @@`
`1583`	`1583`	`{`
`1584`	`1584`	`"name": "last"`
`1585`	`1585`	`},`
	`1586`	`+ {`
	`1587`	`+ "name": "last3"`
	`1588`	`+ },`
`1586`	`1589`	`{`
`1587`	`1590`	`"name": "lastNodeWasCreated"`
`1588`	`1591`	`},`
Original file line number	Diff line number	Diff line change
`@@ -57,6 +57,13 @@ export function equalArraysOrString(a: string\|string[], b: string\|string[]) {`
`57`	`57`	`}`
`58`	`58`	`}`
`59`	`59`
	`60`	`+/**`
	`61`	`+ * Return the last element of an array.`
	`62`	`+ */`
	`63`	`+export function last<T>(a: T[]): T\|null {`
	`64`	`+ return a.length > 0 ? a[a.length - 1] : null;`
	`65`	`+}`
	`66`	`+`
`60`	`67`	`export function wrapIntoObservable<T>(value: T\|Promise<T>\|Observable<T>): Observable<T> {`
`61`	`68`	`if (isObservable(value)) {`
`62`	`69`	`return value;`