fix(migrations): flip the default standalone flag in route-lazy-loading migration (angular#58474)

Before v19, the default value of the standalone flag was false, this code change flips the logic in the migration to make it true by default.

PR Close angular#58474

Author: eneajaho

packages/core/schematics/ng-generate/route-lazy-loading/util.ts

@@ -23,7 +23,11 @@ export function isStandaloneComponent(node: ts.ClassDeclaration): boolean {
     const arg = decorator.expression.arguments[0];
     if (ts.isObjectLiteralExpression(arg)) {
       const property = findLiteralProperty(arg, 'standalone') as ts.PropertyAssignment;
-      return property ? property.initializer.getText() === 'true' : false;
+      if (property) {
+        return property.initializer.getText() === 'true';
+      } else {
+        return true; // standalone is true by default in v19
+      }
     }
   }
 

packages/core/schematics/test/standalone_routes_spec.ts

@@ -335,11 +335,13 @@ describe('route lazy loading migration', () => {
       import {NgModule} from '@angular/core';
       import {provideRoutes} from '@angular/router';
       import {TestComponent} from './test';
+      import {StandaloneByDefaultComponent} from './standalone-by-default';
       import {NotStandaloneComponent} from './not-standalone';
 
       const routes = [
         {path: 'test', component: TestComponent},
         {path: 'test1', component: NotStandaloneComponent},
+        {path: 'test2', component: StandaloneByDefaultComponent},
       ];
 
       @NgModule({
@@ -358,11 +360,20 @@ describe('route lazy loading migration', () => {
     `,
     );
 
+    writeFile(
+      'standalone-by-default.ts',
+      `
+      import {Component} from '@angular/core';
+      @Component({template: 'hello'})
+      export class StandaloneByDefaultComponent {}
+    `,
+    );
+
     writeFile(
       'not-standalone.ts',
       `
       import {Component, NgModule} from '@angular/core';
-      @Component({template: 'hello'})
+      @Component({template: 'hello', standalone: false})
       export class NotStandaloneComponent {}
 
       @NgModule({declarations: [NotStandaloneComponent], exports: [NotStandaloneComponent]})
@@ -381,6 +392,7 @@ describe('route lazy loading migration', () => {
         const routes = [
           {path: 'test', loadComponent: () => import('./test').then(m => m.TestComponent)},
           {path: 'test1', component: NotStandaloneComponent},
+          {path: 'test2', loadComponent: () => import('./standalone-by-default').then(m => m.StandaloneByDefaultComponent)},
         ];
 
         @NgModule({