Improve entity reference validation error messages

Fixed the error message, added field name with the wrong value for more clarity.

Fixed failed test case.

I tried to change the error message 'There are no entities matching "invalid reference"' to 'Invalid value "value" chosen for "field_name"'. I made a change in the EntityAutocomplete file by adding the name of the field entity reference. In method 'matchEntityByTitle' $element is a form element i.e entity reference field. So I used it's title attribute to get the label of the field.
There are 4 test cases that need to be updated. While fixing test cases I realized there can be entity reference field without the label. In one of the cases, entity reference field is used as an exposed filter without a label so test case failed. I could think of one solution as if a title is available then I used a new error message with a field name in it and if not then using the previous error. What can be the better solution for this case when the title for the field is not available? Also, will it be good if I try using the machine name of the field instead of title? Please suggest.

Hi @z.stolar, I tried finding a label for field but couldn't get. In matchEntityByTitle() method in EntityAutocpmplete file, element is just an array. Couldn't find anything related to a label. Here attaching element variable, both with title and without title.
With title:

array (size=44)
  '#type' => string 'entity_autocomplete' (length=19)
  '#title' => 
    object(Drupal\Core\StringTranslation\TranslatableMarkup)[1192]
      protected 'translatedMarkup' => null
      protected 'options' => 
        array (size=0)
          empty
      protected 'stringTranslation' => 
        object(Drupal\Core\StringTranslation\TranslationManager)[609]
          protected 'translators' => 
            array (size=1)
              ...
          protected 'sortedTranslators' => 
            array (size=1)
              ...
          protected 'defaultLangcode' => string 'en' (length=2)
          public '_serviceId' => string 'string_translation' (length=18)
      protected 'string' => string 'Usernames' (length=9)
      protected 'arguments' => 
        array (size=0)
          empty
  '#description' => 
    object(Drupal\Core\StringTranslation\TranslatableMarkup)[1193]
      protected 'translatedMarkup' => null
      protected 'options' => 
        array (size=0)
          empty
      protected 'stringTranslation' => 
        object(Drupal\Core\StringTranslation\TranslationManager)[609]
          protected 'translators' => 
            array (size=1)
              ...
          protected 'sortedTranslators' => 
            array (size=1)
              ...
          protected 'defaultLangcode' => string 'en' (length=2)
          public '_serviceId' => string 'string_translation' (length=18)
      protected 'string' => string 'Enter a comma separated list of user names.' (length=43)
      protected 'arguments' => 
        array (size=0)
          empty
  '#target_type' => string 'user' (length=4)
  '#tags' => boolean true
  '#default_value' => string '' (length=0)
  '#process_default_value' => boolean true
  '#prefix' => string '<div class="views-group-box views-right-60">' (length=44)
  '#suffix' => string '</div>' (length=6)
  '#input' => boolean true
  '#size' => int 60
  '#maxlength' => int 128
  '#autocomplete_route_name' => string 'system.entity_autocomplete' (length=26)
  '#process' => 
    array (size=5)
      0 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processEntityAutocomplete' (length=25)
      1 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processAutocomplete' (length=19)
      2 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processAjaxForm' (length=15)
      3 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processPattern' (length=14)
      4 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processGroup' (length=12)
  '#pre_render' => 
    array (size=2)
      0 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'preRenderTextfield' (length=18)
      1 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'preRenderGroup' (length=14)
  '#theme' => string 'input__textfield' (length=16)
  '#theme_wrappers' => 
    array (size=1)
      0 => string 'form_element' (length=12)
  '#selection_handler' => string 'default' (length=7)
  '#selection_settings' => 
    array (size=0)
      empty
  '#autocreate' => null
  '#validate_reference' => boolean true
  '#element_validate' => 
    array (size=1)
      0 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'validateEntityAutocomplete' (length=26)
  '#value_callback' => 
    array (size=2)
      0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
      1 => string 'valueCallback' (length=13)
  '#defaults_loaded' => boolean true
  '#tree' => boolean true
  '#parents' => 
    array (size=2)
      0 => string 'options' (length=7)
      1 => string 'value' (length=5)
  '#array_parents' => 
    array (size=2)
      0 => string 'options' (length=7)
      1 => string 'value' (length=5)
  '#weight' => float 0.009
  '#processed' => boolean true
  '#required' => boolean false
  '#attributes' => 
    array (size=4)
      'data-drupal-selector' => string 'edit-options-value' (length=18)
      'aria-describedby' => string 'edit-options-value--description' (length=31)
      'class' => 
        array (size=1)
          0 => string 'form-autocomplete' (length=17)
      'data-autocomplete-path' => string '/entity_reference_autocomplete/user/default/OnXbnUTlSESRFkxZ9HpZlH1Qb64nnI0UJFb8xPnOSC0' (length=87)
  '#title_display' => string 'before' (length=6)
  '#description_display' => string 'after' (length=5)
  '#errors' => null
  '#id' => string 'edit-options-value' (length=18)
  '#name' => string 'options[value]' (length=14)
  '#value' => string 'v2zvloui' (length=8)
  '#needs_validation' => boolean true
  '#autocomplete_route_parameters' => 
    array (size=3)
      'target_type' => string 'user' (length=4)
      'selection_handler' => string 'default' (length=7)
      'selection_settings_key' => string 'OnXbnUTlSESRFkxZ9HpZlH1Qb64nnI0UJFb8xPnOSC0' (length=43)
  '#cache' => 
    array (size=3)
      'contexts' => 
        array (size=0)
          empty
      'tags' => 
        array (size=0)
          empty
      'max-age' => int -1
  '#attached' => 
    array (size=1)
      'library' => 
        array (size=1)
          0 => string 'core/drupal.autocomplete' (length=24)
  '#ajax_processed' => boolean false
  '#groups' => 
    array (size=16)
      'options][admin_label' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][more' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose_button][checkbox][checkbox' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][value' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][required' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][label' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][description' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][use_operator' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][operator_limit_selection' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][operator_id' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][remember' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][remember_roles][anonymous' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][remember_roles][authenticated' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][remember_roles][zfqpx43n' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][identifier' => 
        array (size=1)
          '#group_exists' => boolean true
      'options][expose][reduce' => 
        array (size=1)
          '#group_exists' => boolean true
  '#sorted' => boolean true

Without title

array (size=41)
  '#type' => string 'entity_autocomplete' (length=19)
  '#description' => 
    object(Drupal\Core\StringTranslation\TranslatableMarkup)[3006]
      protected 'translatedMarkup' => null
      protected 'options' => 
        array (size=0)
          empty
      protected 'stringTranslation' => 
        object(Drupal\Core\StringTranslation\TranslationManager)[611]
          protected 'translators' => 
            array (size=1)
              ...
          protected 'sortedTranslators' => 
            array (size=1)
              ...
          protected 'defaultLangcode' => string 'en' (length=2)
          public '_serviceId' => string 'string_translation' (length=18)
      protected 'string' => string 'Enter a comma separated list of user names.' (length=43)
      protected 'arguments' => 
        array (size=0)
          empty
  '#target_type' => string 'user' (length=4)
  '#tags' => boolean true
  '#default_value' => string '' (length=0)
  '#process_default_value' => boolean true
  '#input' => boolean true
  '#size' => int 60
  '#maxlength' => int 128
  '#autocomplete_route_name' => string 'system.entity_autocomplete' (length=26)
  '#process' => 
    array (size=5)
      0 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processEntityAutocomplete' (length=25)
      1 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processAutocomplete' (length=19)
      2 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processAjaxForm' (length=15)
      3 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processPattern' (length=14)
      4 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'processGroup' (length=12)
  '#pre_render' => 
    array (size=2)
      0 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'preRenderTextfield' (length=18)
      1 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'preRenderGroup' (length=14)
  '#theme' => string 'input__textfield' (length=16)
  '#theme_wrappers' => 
    array (size=1)
      0 => string 'form_element' (length=12)
  '#selection_handler' => string 'default' (length=7)
  '#selection_settings' => 
    array (size=0)
      empty
  '#autocreate' => null
  '#validate_reference' => boolean true
  '#element_validate' => 
    array (size=1)
      0 => 
        array (size=2)
          0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
          1 => string 'validateEntityAutocomplete' (length=26)
  '#value_callback' => 
    array (size=2)
      0 => string 'Drupal\Core\Entity\Element\EntityAutocomplete' (length=45)
      1 => string 'valueCallback' (length=13)
  '#defaults_loaded' => boolean true
  '#tree' => boolean false
  '#parents' => 
    array (size=1)
      0 => string 'uid' (length=3)
  '#array_parents' => 
    array (size=1)
      0 => string 'uid' (length=3)
  '#weight' => int 0
  '#processed' => boolean true
  '#required' => boolean false
  '#attributes' => 
    array (size=4)
      'data-drupal-selector' => string 'edit-uid' (length=8)
      'aria-describedby' => string 'edit-uid--description' (length=21)
      'class' => 
        array (size=1)
          0 => string 'form-autocomplete' (length=17)
      'data-autocomplete-path' => string '/entity_reference_autocomplete/user/default/-LmIlVCwMAybEDzB-KNeV8IxWG5pRW61Ou9Kd06flNg' (length=87)
  '#title_display' => string 'before' (length=6)
  '#description_display' => string 'after' (length=5)
  '#errors' => null
  '#id' => string 'edit-uid' (length=8)
  '#name' => string 'uid' (length=3)
  '#value' => string 'oolgthqt' (length=8)
  '#needs_validation' => boolean true
  '#autocomplete_route_parameters' => 
    array (size=3)
      'target_type' => string 'user' (length=4)
      'selection_handler' => string 'default' (length=7)
      'selection_settings_key' => string '-LmIlVCwMAybEDzB-KNeV8IxWG5pRW61Ou9Kd06flNg' (length=43)
  '#cache' => 
    array (size=3)
      'contexts' => 
        array (size=0)
          empty
      'tags' => 
        array (size=0)
          empty
      'max-age' => int -1
  '#attached' => 
    array (size=1)
      'library' => 
        array (size=1)
          0 => string 'core/drupal.autocomplete' (length=24)
  '#ajax_processed' => boolean false
  '#groups' => 
    array (size=1)
      'uid' => 
        array (size=1)
          '#group_exists' => boolean true
  '#sorted' => boolean true

+++ b/core/lib/Drupal/Core/Entity/Element/EntityAutocomplete.php
@@ -281,7 +281,12 @@ protected static function matchEntityByTitle(SelectionInterface $handler, $input
-        $form_state->setError($element, t('There are no entities matching "%value".', $params));
+        if(isset($element['#title'])){
+          $form_state->setError($element, t('Invalid value "%value" chosen for "%field_name".', $params + ['%field_name' => $element['#title']]));
+        }
+        else{
+          $form_state->setError($element, t('There are no entities matching "%value".', $params));
+        }

I don't think we should be including the field name in the error text - this would be incorrect for inline form errors module - for example. And also we don't do this for other form errors.

One thing we can do to improve this message is use the entity type label information. We'll need to get the type from the entity type manager. I think \Drupal::entityTypeManager()->getDefinition($element['#target_type'])->getPluralLabel() might work.

@alexpott I have checked #9 with "Inline Form Errors" module it's working fine.

I am working on it

Uploaded patch as per the suggestion in #15, Please review

+++ b/core/lib/Drupal/Core/Entity/Element/EntityAutocomplete.php
@@ -327,7 +327,13 @@ protected static function matchEntityByTitle(SelectionInterface $handler, $input
     if (empty($entities)) {
       if ($strict) {
         // Error if there are no entities available for a required field.
-        $form_state->setError($element, t('There are no entities matching "%value".', $params));
+        $entity_type_label = \Drupal::entityTypeManager()->getDefinition($element['#target_type'])->getPluralLabel();
+        if (isset($entity_type_label)) {
+          $form_state->setError($element, t('Invalid value "%value" chosen for "%field_name".', $params + ['%field_name' => $entity_type_label]));
+        }
+        else{
+          $form_state->setError($element, t('There are no entities matching "%value".', $params));
+        }

placeholder is still field name now which doesn't make sense and the tests need to be updated to match what we display now.

1) Applied changes according to #15 and adjusted tests as was pointed in #22;
2) Also, added labels for other types of validation messages in EntityAutocomplete.php;

I didn't find test for the following message:
"Many @entities are called %value. Specify the one you want by appending the id in parentheses, like "@value (@id)"."

Should we add a test coverage for this particular case?

Updated the issue summary and title.
Is there anything else we can do to move the issue forward?

+++ b/core/lib/Drupal/Core/Entity/Element/EntityAutocomplete.php
@@ -323,17 +323,18 @@ protected static function matchEntityByTitle(SelectionInterface $handler, $input
+      '@entities' => \Drupal::entityTypeManager()->getDefinition($element['#target_type'])->getPluralLabel(),

Can we rename the @entities parameter to @entity_type_plural for more clarity?

Other than that, the patch looks really good to me :)

Thanks, here is the updated patch.

Changing the component, because there are no changes in entity_reference module.

Looks ready to go!

This looks great, but needs a re-roll.

Will open merge request soon.

The merge request with re-roll is open.
Moving back to RTBC as per #31.

Committed f0a40c9 and pushed to 9.2.x. Thanks!

Updating the tags as it broke DER HEAD as well.