PHP 7.4 notice in views node wizard if a taxonomy field widget is hidden

We triaged this as part of a bug smash initiative call and confirmed this is a valid bug report.

We'll need a test here.

I am having the same problem in 8.9.1 as well. I have a taxonomy reference field that is hidden.

@bkosborne patch working
Before patch

After patch

I think we can use the !empty here. I have created another patch.

@vishnukumar, the given patch works fine.

I had the same problem with the flag-module:
Core: 9.0.7
Flag: 8.x-4.0-beta2

Error on admin/structure/views/add:

Notice: Trying to access array offset on value of type null in Drupal\node\Plugin\views\wizard\Node->buildFilters() (Zeile 282 in /web/core/modules/node/src/Plugin/views/wizard/Node.php).:

Applying the patch removed the error.

I really don't know what we can test here. The piece of code works as it is expected even if the PHP notice is presented. I tried to find a test case that breaks 'Add view' page functionality. No success. It looks like we have a PHP notice and nothing else. Any help or suggestions?

Let's see what TestBot thinks of this test.

Test fails without patch, test pass with patch => Needs Review

Oops...

Fixed Coding Standard message and incorrect declaration of $modules.

Fixed Coding Standard message

Thank you @Spokje for your test-only patch. Now I know how to test this kind of bugs :)

I am marking RTBC since:

1. #20 patch applies cleanly.
2. Tests pass.
3. #20 test-only patch fails as expected.
4. No coding standard problems were found by the test bot.
5. Code is clear and addresses the issue from the issue summary.
6. Feedback from previous comments has been addressed.
7. Issue title is clear and relevant.
8. Issue metadata looks okay.
9. Manually tested and patch works as expected. See screenshots at #6. I can confirm the same result for the #20 patch.

This fix looks good.

+++ b/core/modules/views/tests/src/Functional/Wizard/HiddenTaxonomyTermReferenceFieldTest.php
@@ -0,0 +1,62 @@
+use Drupal\Core\Field\FieldStorageDefinitionInterface;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+
+/**
+ * Tests node wizard and content type with hidden Taxonomy Term Reference field.
+ *
+ * @group Views
+ * @group node
+ */
+class HiddenTaxonomyTermReferenceFieldTest extends WizardTestBase {

Given this is a bug in node module code this test should be in the Node module. See \Drupal\Tests\node\Functional\Views\NodeRevisionWizardTest for example. If we move the code and change the namespace we should be good to go.

Given this is a bug in node module code this test should be in the Node module.

Argh, should have caught that one myself.

Got a bit frisky and moved this test and \Drupal\Tests\node\Functional\Views\NodeRevisionWizardTest to a new folder core/modules/node/tests/src/Functional/Views/Wizard and namespace Drupal\Tests\node\Functional\Views\Wizard to keep the View Wizard tests (now a whopping number of 2) in \Drupal\Tests\node\Functional\Views together.
Hope this isn't out of scope.

Right....

Needs testing against PHP7.4 and I somehow messed up the test-only-fail patch.

Let's try that again...

+++ b/core/modules/node/src/Plugin/views/wizard/Node.php
@@ -279,7 +279,7 @@ protected function buildFilters(&$form, FormStateInterface $form_state) {
         $widget = $display->getComponent($field_name);
         // We define "tag-like" taxonomy fields as ones that use the
         // "Autocomplete (Tags style)" widget.
-        if ($widget['type'] == 'entity_reference_autocomplete_tags') {
+        if (!empty($widget) && $widget['type'] == 'entity_reference_autocomplete_tags') {
           $tag_fields[$field_name] = $field;
         }

The logic above here is looping around this already... so we're doing more loops than is really necessary.

We can combine the two by doing...

      $tag_fields += array_filter($this->entityFieldManager->getFieldDefinitions($this->entityTypeId, $bundle), function (FieldDefinitionInterface $field_definition) use ($display) {
        if ($field_definition->getType() == 'entity_reference' && $field_definition->getSetting('target_type') == 'taxonomy_term') {
          $widget = $display->getComponent($field_definition->getName());
          return isset($widget['type']) && $widget['type'] == 'entity_reference_autocomplete_tags';
        }
        return FALSE;
      });

Can you open a follow-up for this? Shouldn't be part of the change here.

@alexpott: Ah, TBH: I haven't had a thorough look at the actual fix, just whacked together the Test bit.

But I agree to not get "too loopy", follow-up created here: [PP-1 ]Make bug-fix code for #3167733 (PHP 7.4 notice in views node wizard if a taxonomy field widget is hidden) more efficient

Back to RTBC, counting that we have follow up now.

Thanks to everyone!

Committed and pushed 9b75b5807b to 9.2.x and bc64f97f83 to 9.1.x. Thanks!

Backported to 9.1.x as a non-disruptive bugfix.

Providing a backport patch for 8.9.13