Third option for the CKEditor 4 "Language" button: `enabled` (in addition to `un` and `all`)

By complete coincidence I was working on this exact issue last Friday. While it does not solve your exact request, it does allow for customizing of the languages dropdown via the configurable Drupal languages list, with a new option in ckeditor to pull languages from the internal system. https://git.drupalcode.org/project/drupal/-/merge_requests/1665

I agree, a configurable list is the only solution that makes sense.

In 14 years of Drupal development I have never had to build a site that supports exactly these 6 official UN languages. To even offer that option seems rather arbitrary. IMHO it should be removed, but at least it should not be the default.

At the risk of stretching the scope of this issue, I would propose offering 3 options:
- All enabled languages [default]
- All languages
- Selected languages
The third option should reveal an additional form element to select languages.

@jwaxo, i am sure years until this would ever get merged, so would a patch file not be more useful here? Do you know if possible to create a patch file from gitlab MR? Of course i can manually make the edits and then create a patch.. :(

found it.

Tested the patch on 9.2.11 and works as expected. Thanks for this; hopefully gets merged to core.

Thanks for the patch. To get it in core, it needs tests.

@liquidcms Creating a patch from a a merge request is surprisingly easy. See https://www.drupal.org/docs/develop/git/using-git-to-contribute-to-drupa.... Do make sure you save the patch in your local project and not use the URL directly; you don't want any arbitrary pushes changing the actual patch applied to your project.

The language button now includes a drop-down for "enabled languages".
If a custom language has been added to the site, then this also shows up in the list of enabled languages.

This would also be relevant for the CKEditor 5 module.

Sibling CKEditor 5 issue: #3273986: Third option for the CKEditor 5 "Language" button: `site_configured` (in addition to `un` and `all`).

Either we should expand the scope of this issue to also do the work for CKEditor 5, or that issue needs to be postponed on this one, because this will require changes in the CKEditor 4 to 5 upgrade path.

Patch review

Patch looks great, just one nit:

+++ b/core/modules/ckeditor/src/Plugin/CKEditorPlugin/Language.php
@@ -53,9 +53,28 @@ public function getConfig(Editor $editor) {
+        $predefined_languages = LanguageManager::getStandardLanguageList();
+
+        break;
...
+        }
+
+        break;

Nit: no blank line before the break;.

I've changed the wording for the third option and the description in the same way as in the related issue for CKEditor5 #3273986: Third option for the CKEditor 5 "Language" button: `site_configured` (in addition to `un` and `all`), fixed the coding standard errors, and updated the test.

I'm adding a new patch to just change the wording, but it still needs the test required in #11

CKEditor has been removed from core, CKEditor 4 is removed from Drupal Core in 10.0.0

There's been progress on the CKEditor 5 issue at #3273986: Third option for the CKEditor 5 "Language" button: `site_configured` (in addition to `un` and `all`) and there may be improvements from that issue to introduce here to keep them in parallel.

In that issue, I felt that "enabled" was unclear (enabled how - per the input format settings, the site's configured languages, or some other method?), and substituted "enabled" for "site_configured" so that an option like the one suggested in #7 here and #3375157: [upstream] CKEditor 5 language selector cannot be scrolled if "All NNN languages" option selected could use another term like "format_plugin" and the values would be meaningful.