Term multiplication for new Term values added for Term fields with autocomplete widget on multiple references fields

i can confirm this issue
Term multiplication for new Term values added for Term fields with autocomplete widget on multiple references fields.
This happens because of taxonomy autocomplete widget implementation
https://api.drupal.org/api/drupal/modules!taxonomy!taxonomy.module/funct...
&
https://api.drupal.org/api/drupal/modules!taxonomy!taxonomy.module/funct...

i do not know what to say about solution suggested by previous patch/post.

the only thing i can think of, is a custom validation for taxonomy term reference fields that have the autocomplete widget or 'autocreate' tid defined before saving the Entity from IEF.

any other suggestions, ideeas?

Hi, I encountered the same problem. To solve this problem, I wrote a small module with this code:

function hook_field_attach_presave($entity_type, $entity) {
  // Change $entity->vid == 6 to your vocabulary id.
  if ($entity_type == 'taxonomy_term' && $entity->vid == 6) {
    $term = db_select('taxonomy_term_data', 't')
      ->fields('t', array('tid', 'name'))
      ->condition('t.vid', $entity->vid)
      ->condition('t.name', drupal_strtolower(trim($entity->name)))
      ->execute()
      ->fetchAssoc();

    if (!empty($term)) {
      $entity->name = $term['name'];
      $entity->tid = $term['tid'];
    }
  }
}

@zestagio : nice solution you found - an extra validation just before saving.
thank you Sir.

here is patch that use your approach and which seems to solve this issue.

This is a core bug of autocomplete widget, so should be fixed in 8.x first and then backported to 7.x

Steps to reproduce:
1) add another Tags2 term reference field to article node type
2) visit /node/add/article
3) enter 'test' in Tags field and the same 'test' into Tags2 field
4) save article
5) now each field value has different terms assigned but with the same name 'test'

expected result - only one term 'test' should be added to Tags vocabulary and both fields should point to that one

test2 term points to different terms

indeed.
do you want to take care of this or may I?

any suggestions about the implementation?
should be in taxonomy_field_validate() or in taxonomy_field_presave() or other place?

I don't see how this is a bug in Entity reference. Even core's taxonomy UI lets you add different terms with the same name, so this is really not our job to 'fix'.. because there's nothing to fix.

Ok, I need to expand my comment: .. nothing to fix in Entity reference, or Term reference for that matter.

As long as taxonomy.module allows terms with the same name, what you describe has to be fixed by adding that unique name check to a vocabulary.

@amateescu Please read my example. Autocomplete widget should be fixed (probably for taxonomy) because it allows to add same term twice.
It's not about adding same term twice - it's about logic for autocomplete which checks existence of item only once that leads to erroneous addition.
Proper implementation should not allow duplication and after you re-save the node second term would be lost (autocomplete will find first term and replace Tags2 value with it)

I think 'autocreate' assignment should be moved to taxonomy_field_presave() from taxonomy_field_validate() or taxonomy_field_presave() should check for newly created value again.

Also probably entity reference has the same issue

i agree that Term reference field with autocomplete widget doesn't work properly.
About Entity Reference fields, it should be other issue.

about this issue as D8 core issue, here is a patch - save the same term for the same vocabulary only once..
i also remove "autocreate", as there's no more needed.

@vasike great! now needs some tests

Fixing wording

This is essentially a reroll of #14, although the logic has completely moved. I've also added a test, and included just the test to show that it fails without this fix.

Oops, critical logic error in #16.

The fix above breaks preview functionality. I've rolled a patch that gets those tests working again, but doesn't fix the issue at hand. Setting to needs review to re-run tests (that will fail).

I think this is a duplicate of #1343822: Autocreated taxonomy terms duplicated if they are added to multiple fields and is outdated.

Very similar to https://www.drupal.org/project/drupal/issues/1343822 but think slightly different (least from the description)

Closing as cannot reproduce in Drupal 9.5

Added a taxonomy field. Added red, red and verified red was only saved once.

If you still feel this is an issue please reopen with an update issue summary and steps to reproduce.