Provide a mechanism to mark entire twig templates as deprecated

YES! This will be very useful. Could we get a change record how it's expected to deprecate a template.

Change record is still missing but everything else looks good.

Added the change record.Marking it NR again.

Thanks for the change record @Utkarsh_33! Made few edits there.

CR reads well I think!

Think this should be a 10.2 highlight?

In #5 I said that we should trigger deprecation error for preprocess functions, template overrides etc, but I don't know if that's actually true. We want themes to keep their support for the template until the template has been removed. This could mean that themes are left with left over templates and preprocess function but this seems less of a problem than breaking existing uses of the template.

Maybe the next step would be something like hook_removed_themes() which would allow us to define deleted theme hooks in the next major and then trigger a deprecation warning for the left over preprocess functions and templates. Thoughts on this?

@lauriii maybe even just extend the hook_theme API in the same way and declare a 'removed' or 'obsolete' key instead of 'deprecated'?

This also needs to have the Deprecation policy updated with an example usage.

#23 that seems like a good idea!

So I guess what's still needed per #24 is updating https://www.drupal.org/about/core/policies/core-change-policies/drupal-d... → 😇

Let's see what the example will look like. This would go on Drupal deprecation policy → . I suggest near the end, after 'Configuration schema'.

Twig template

/**
  * Implements hook_theme().
  */
function node_theme() {
  return [
    'foo_template' => [
      'variables' => ['content' => NULL],
      'deprecated' => 'The "foo_template" template is deprecated in drupal:9.2.3 and is removed from drupal:11.0.0. Use "bar_template" instead. See https://www.drupal.org/node/123456',
    ],
  ];
}

NW for additional documentation.

Not quite what I meant - we need some words to explain the deprecated key.

Looks good to me. Suggested some textual changes.

All threads appear to have been resolved. Think this would be a good one to get in as I imagine some templates could be deprecated before D11 vs just removed.

+1 as all the points are addressed.

lauriii → closed merge request !4666

I think we need a followup for #23.

Committed 8470213 and pushed to 11.x. Also cherry-picked to 10.2.x. Thanks!

Filed the follow-up: 📌 Allow marking theme templates as obsolete Active .

Ah, there is still work to do here. The policy documents have not been updated.

I also think this needs a follow up to change the the key name, 'deprecated' because that sounds like a boolean when it is really a message, so should be 'deprecation_message'. And that would align this with the unfinished issue to create a way to declare a plugin as deprecated. 📌 Create a way to declare a plugin as deprecated Needs work .

@lauriii, my apologies, I now see the policy update! I don't know why my search failed before.

Please make sure there is an Upgrade Status issue! There is already some hook_theme coverage there thanks to @lauriii I think :) but that would need to be extended now.

#40: I agree that deprecated_message could be clearer. However, I personally would prefer to keep it as deprecated since that's what we use already for config schema and library definitions. It could be annoying to have to remember when we are using deprecated vs deprecated_message. Feel free to open a follow-up issue to discuss further if you feel strongly about this.

#43: Thanks, I didn't realize there was precedence.

Upgrade status issue made, 📌 Add check for deprecated twig template Active

Automatically closed - issue fixed for 2 weeks with no activity.