Provide a way to show a message if the product variation is disabled.

When I disable the variations of a product and I am on the product page, the following error is displayed :

The website encountered an unexpected error. Please try again later.

TypeError: Argument 2 passed to Drupal\commerce_product\ProductVariationFieldRenderer::renderField() must implement interface Drupal\commerce_product\Entity\ProductVariationInterface, null given, called in /home/www.s1biose.com/public_html/web/modules/contrib/commerce/modules/product/src/Plugin/DsField/ProductVariationField.php on line 33 in Drupal\commerce_product\ProductVariationFieldRenderer->renderField() (line 79 of /home/www.s1biose.com/public_html/web/modules/contrib/commerce/modules/product/src/ProductVariationFieldRenderer.php) #0 /home/www.s1biose.com/public_html/web/modules/contrib/commerce/modules/product/src/Plugin/DsField/ProductVariationField.php(33): Drupal\commerce_product\ProductVariationFieldRenderer->renderField('sku', NULL, Array) #1 /home/www.s1biose.com/public_html/web/modules/contrib/ds/ds.module(365): Drupal\commerce_product\Plugin\DsField\ProductVariationField->build() #2 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Extension/ModuleHandler.php(501): ds_entity_view_alter(Array, Object(Drupal\commerce_product\Entity\Product), Object(Drupal\Core\Entity\Entity\EntityViewDisplay)) #3 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Entity/EntityViewBuilder.php(285): Drupal\Core\Extension\ModuleHandler->alter('commerce_produc...', Array, Object(Drupal\commerce_product\Entity\Product), Object(Drupal\Core\Entity\Entity\EntityViewDisplay)) #4 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Entity/EntityViewBuilder.php(220): Drupal\Core\Entity\EntityViewBuilder->buildMultiple(Array) #5 [internal function]: Drupal\Core\Entity\EntityViewBuilder->build(Array) #6 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Render/Renderer.php(376): call_user_func(Array, Array) #7 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Render/Renderer.php(195): Drupal\Core\Render\Renderer->doRender(Array, false) #8 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(226): Drupal\Core\Render\Renderer->render(Array, false) #9 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Render/Renderer.php(574): Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}() #10 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(227): Drupal\Core\Render\Renderer->executeInRenderContext(Object(Drupal\Core\Render\RenderContext), Object(Closure)) #11 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(117): Drupal\Core\Render\MainContent\HtmlRenderer->prepare(Array, Object(Symfony\Component\HttpFoundation\Request), Object(Drupal\Core\Routing\CurrentRouteMatch)) #12 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/EventSubscriber/MainContentViewSubscriber.php(90): Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse(Array, Object(Symfony\Component\HttpFoundation\Request), Object(Drupal\Core\Routing\CurrentRouteMatch)) #13 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php(111): Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray(Object(Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent), 'kernel.view', Object(Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher)) #14 /home/www.s1biose.com/public_html/vendor/symfony/http-kernel/HttpKernel.php(149): Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch('kernel.view', Object(Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent)) #15 /home/www.s1biose.com/public_html/vendor/symfony/http-kernel/HttpKernel.php(64): Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object(Symfony\Component\HttpFoundation\Request), 1) #16 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/StackMiddleware/Session.php(57): Symfony\Component\HttpKernel\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #17 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(47): Drupal\Core\StackMiddleware\Session->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #18 /home/www.s1biose.com/public_html/web/core/modules/page_cache/src/StackMiddleware/PageCache.php(99): Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #19 /home/www.s1biose.com/public_html/web/core/modules/page_cache/src/StackMiddleware/PageCache.php(78): Drupal\page_cache\StackMiddleware\PageCache->pass(Object(Symfony\Component\HttpFoundation\Request), 1, true) #20 /home/www.s1biose.com/public_html/web/core/modules/ban/src/BanMiddleware.php(50): Drupal\page_cache\StackMiddleware\PageCache->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #21 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(47): Drupal\ban\BanMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #22 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(50): Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #23 /home/www.s1biose.com/public_html/vendor/stack/builder/src/Stack/StackedHttpKernel.php(23): Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #24 /home/www.s1biose.com/public_html/web/core/lib/Drupal/Core/DrupalKernel.php(656): Stack\StackedHttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #25 /home/www.s1biose.com/public_html/web/index.php(19): Drupal\Core\DrupalKernel->handle(Object(Symfony\Component\HttpFoundation\Request)) #26 {main}.

Thank you, indeed I had applied the following patch :
https://www.drupal.org/files/issues/2723689-3-add-ds-integration.patch
When I delete it, it works.

Thank you, indeed I had applied the following patch:
When I delete it, it works.

But I still have the same problem with the price and the reference that does not show up. I never succeeded in resolving this.
Commerce 2 is really very complicated.

I use "Display Suite" for displaying product pages.
I copied the file "bs-2col-stacked--commerce-product.html.twig" into the templates folder of my theme.
Here are contents :

{#
/**
 * @file
 * Bootstrap Layouts: "2 Columns (stacked)" template.
 *
 * Available layout variables:
 * - wrapper: Wrapper element for the layout container.
 * - attributes: Wrapper attributes for the layout container.
 *
 * Available region variables:
 * - top
 * - left
 * - right
 * - bottom
 *
 * Each region variable contains the following properties:
 * - wrapper: The HTML element to use to wrap this region.
 * - attributes: The HTML attributes to use on the wrapper for this region.
 * - content: The content to go inside the wrapper for this region.
 */
#}
<{{ wrapper }}{{ attributes }}>
  {{ title_suffix.contextual_links }}

  {% if top.content %}
  <{{ top.wrapper }}{{ top.attributes }}>
    {{ top.content }}
  </{{ top.wrapper }}>
  {% endif %}

  {% if left.content %}
  <{{ left.wrapper }}{{ left.attributes }}>
    {{ left.content }}
  </{{ left.wrapper }}>
  {% endif %}

  {% if right.content %}
  <{{ right.wrapper }}{{ right.attributes }}>
    {{ right.content }}
  </{{ right.wrapper }}>
  {% endif %}

  {% if bottom.content %}
  <{{ bottom.wrapper }}{{ bottom.attributes }}>
    {{ bottom.content }}
  </{{ bottom.wrapper }}>
  {% endif %}

</{{ wrapper }}>

What should I do ?

I also encounter problems with views and product variations.

It's a nightmare.

Thank you

I think providing a way to display needed information could be very useful. But first, we could decide how and what to theme. Here, some points/ideas:

1. Using a global wrapper template (this will wrap the form or the "Out of stock" message), with needed variables. This could allow using same template for several view modes, instead theming each view mode to know the status (if needed/possible), and allowing themers to know if form is enabled/disabled at top of the element.
2. Keeping default form as it's being used currently (no changes). but show a themed output only when variation is disabled. Same as previous: Allowing to theme per view_mode (if needed/possible).
3. Using a different theme for each case: if form and if disabled. Both cases they should provide needed variables, and the output must be as simple as possible.
4. More ideas? :)

Cheers.

Last patch is working fine. I've added some improvements, to allow theming by product bundle, variation bundle and view mode. Added theming description into the README.md.

It should cover at least most of cases related to display "XYZ" message or another, depending context.

Cheers.