Avoid duplicate entry for mass adding terms

codebymikey → changed the visibility of the branch 3014694-avoid-duplicate-entry to hidden.

The MR!52 is tested on Drupal 10.4.7.

The bunch of taxonomy terms is imported successfully without duplicates.
Works properly.

Moving the ticket to RTBC.

It was about time.

can you please fix JSLint, PHPCS errors?

all green! thanks!

I have tested the patch and found an interesting issue, if vocabulary was setup with langcode (but module is not enabled - data and structure has been migrated from D8->D9->D10 and some stage language module might have been enabled) it will not match duplicates.

Maybe add additional langcode check:

      // Check if site is multilingual.
      if ($this->moduleHandler->moduleExists('language')) {
        ...
      }
      else {
        $vocabulary = \Drupal::entityTypeManager()->getStorage('taxonomy_vocabulary')->load($vid);
        $langcode = $vocabulary->get('langcode');
      }

added langcode check for non-multilingual sites

so, I installed a brand new Drupal 11 site, created a couple of vocabs and taxonomy terms,
then installed taxonomy manager with patch (before langcode fix).

Because by default (even without multi-lingual support) langcode is set to 'en' but taxonomy manager is searching for 'und'
so duplicates are added anyway:

After langcode set to 'en' - duplicates are not created (matched to langcode 'en').

There'll be an issue with all terms which were created with taxonomy_manager before this fix (as they are created with langcode 'und')