perf(pagination): Loops in the pagination are now trackedBy.

libs/barista-components/pagination/src/pagination.html

@@ -13,12 +13,17 @@
     </button>
   </li>
 
-  <ng-container *ngFor="let block of _pages; let i = index">
+  <ng-container
+    *ngFor="let block of _pages; let i = index; trackBy: _blockTrackBy"
+  >
     <li *ngIf="i > 0" class="dt-pagination-item">
       <span [attr.aria-label]="_ariaLabelEllipsis">…</span>
     </li>
 
-    <li *ngFor="let page of block" class="dt-pagination-item">
+    <li
+      *ngFor="let page of block; trackBy: _pageTrackBy"
+      class="dt-pagination-item"
+    >
       <button
         *ngIf="page !== currentPage"
         dt-button

libs/barista-components/pagination/src/pagination.ts

@@ -212,6 +212,22 @@ export class DtPagination implements OnInit {
     }
   }
 
+  /**
+   * @internal
+   * Track by function for the outer part of the _pages array loop
+   */
+  _blockTrackBy(_index: number, block: number[]): number {
+    return block.reduce((sum, pageNumber) => sum + pageNumber, 0);
+  }
+
+  /**
+   * @internal
+   * Track by function for the inner part of the _pages array loop
+   */
+  _pageTrackBy(_index: number, page: number): number {
+    return page;
+  }
+
   /**
    * @internal
    * sets the current page and emits the changed event with the current page