Add regression tests for RouterService transitionTo

packages/@ember/routing/route.ts

@@ -2114,6 +2114,17 @@ Route.reopen({
           let options = this._optionsForQueryParam(qp);
           assert('options exists', options && typeof options === 'object');
           if ((get(options, 'refreshModel') as boolean) && this._router.currentState) {
+            // `changed` is computed from router state query params, where default values
+            // may have been pruned during finalization. A later transition can reintroduce
+            // the same serialized value via sticky QP hydration or URL parsing, making the
+            // QP appear changed even though its finalized value is unchanged. Only refresh
+            // the model when the serialized value differs from the last finalized value.
+            if (change in changed) {
+              let newSerializedValue = (changed as Record<string, unknown>)[change];
+              if (newSerializedValue === qp.serializedValue) {
+                continue;
+              }
+            }
             this.refresh();
             break;
           }

packages/ember/tests/routing/router_service_test/transitionTo_test.js

@@ -439,5 +439,121 @@ moduleFor(
         assert.equal(this.routerService.get('currentURL'), '/?url_sort=a');
       });
     }
+
+    async ['@test RouterService#transitionTo with route name and unchanged application query params does not abort or re-run application model hook'](
+      assert
+    ) {
+      assert.expect(3);
+
+      let applicationModelHookCallCount = 0;
+
+      this.add(
+        'route:application',
+        class extends Route {
+          queryParams = {
+            filter: {
+              refreshModel: true,
+            },
+            sort: {
+              refreshModel: true,
+            },
+          };
+
+          model() {
+            applicationModelHookCallCount++;
+            return {};
+          }
+        }
+      );
+
+      this.add(
+        'controller:application',
+        Controller.extend({
+          queryParams: ['filter', 'sort'],
+          filter: '',
+          sort: '',
+        })
+      );
+
+      await this.visit('/?filter=&sort=');
+
+      assert.equal(
+        applicationModelHookCallCount,
+        1,
+        'application model hook called on initial visit'
+      );
+
+      await this.routerService.transitionTo('parent.child');
+
+      assert.equal(
+        this.routerService.get('currentRouteName'),
+        'parent.child',
+        'transitioned to child route'
+      );
+
+      assert.equal(
+        applicationModelHookCallCount,
+        1,
+        'application model hook not re-run when transitioning with unchanged sticky query params'
+      );
+    }
+
+    async ['@test RouterService#transitionTo with URL string and unchanged application query params does not abort or re-run application model hook'](
+      assert
+    ) {
+      assert.expect(3);
+
+      let applicationModelHookCallCount = 0;
+
+      this.add(
+        'route:application',
+        class extends Route {
+          queryParams = {
+            filter: {
+              refreshModel: true,
+            },
+            sort: {
+              refreshModel: true,
+            },
+          };
+
+          model() {
+            applicationModelHookCallCount++;
+            return {};
+          }
+        }
+      );
+
+      this.add(
+        'controller:application',
+        Controller.extend({
+          queryParams: ['filter', 'sort'],
+          filter: '',
+          sort: '',
+        })
+      );
+
+      await this.visit('/?filter=&sort=');
+
+      assert.equal(
+        applicationModelHookCallCount,
+        1,
+        'application model hook called on initial visit'
+      );
+
+      await this.routerService.transitionTo('/child?filter=&sort=');
+
+      assert.equal(
+        this.routerService.get('currentRouteName'),
+        'parent.child',
+        'transitioned to child route'
+      );
+
+      assert.equal(
+        applicationModelHookCallCount,
+        1,
+        'application model hook not re-run when transitioning with unchanged query params'
+      );
+    }
   }
 );