feat(checkout): add error handling for expired purchases in checkout process

src/app/shared/components/cart/cart.component.spec.ts

@@ -367,6 +367,57 @@ describe('CartComponent', () => {
     expect(editingChange).toHaveBeenLastCalledWith(false);
   });
 
+  it('emits Modificar as an action without toggling to Listo', async () => {
+    await TestBed.configureTestingModule({
+      imports: [CartComponent],
+      providers: [
+        {
+          provide: CartService,
+          useValue: {
+            cart: signal(null).asReadonly(),
+            updateItemQuantity: vi.fn(),
+            removeItem: vi.fn(),
+          },
+        },
+        { provide: ModalService, useValue: {} },
+        {
+          provide: ToastService,
+          useValue: { success: vi.fn(), info: vi.fn(), danger: vi.fn() },
+        },
+      ],
+    }).compileComponents();
+
+    const fixture = TestBed.createComponent(CartComponent);
+    fixture.componentRef.setInput('items', [
+      {
+        cartItemId: 10,
+        imageUrl: null,
+        product: 'Producto de prueba',
+        originalPrice: null,
+        discountedPrice: 1000,
+        discountPercentage: null,
+        attributes: [],
+        quantity: 1,
+      },
+    ]);
+    fixture.componentRef.setInput('readonly', true);
+    fixture.componentRef.setInput('showModifyWhenReadonly', true);
+    fixture.componentRef.setInput('modifyAsAction', true);
+    const modify = vi.fn();
+    fixture.componentInstance.modify.subscribe(modify);
+    fixture.detectChanges();
+
+    const modifyButton = fixture.debugElement.query(By.css('.cart-edit-btn'));
+    expect(modifyButton.nativeElement.textContent.trim()).toBe('Modificar');
+
+    modifyButton.nativeElement.click();
+    fixture.detectChanges();
+
+    expect(modify).toHaveBeenCalledOnce();
+    expect(modifyButton.nativeElement.textContent.trim()).toBe('Modificar');
+    expect(fixture.componentInstance.editing()).toBe(false);
+  });
+
   it('allows editing directly when the optional Modificar toggle is disabled', async () => {
     await TestBed.configureTestingModule({
       imports: [CartComponent],