[D8] Entity title length

Thank you for your contribution!
PAReview seems to have issues, at the moment, so I cannot add the PAReview checklist link as I would normally do.

Next, the reviewers will check the project code, and report here what needs to be changed.

  /**
   * Change length of a varchar entity field with data.
   *
   * @param string $entity_type_id
   *   The entity type.
   * @param string $field_name
   *   The field name to change.
   * @param int $field_length
   *   The new length of the field, must be larger than the previous value.
   */
  public function setVarcharField($entity_type_id, $field_name, $field_length) {
    db_change_varchar_field($entity_type_id, $field_name, $field_length);
  }

Why isn't the code directly put in the service method?

db_change_varchar_field() is the wrong function name, for a module whose machine name is entity_title_length.

The module should also implement hook_entity_base_field_info_alter(). Without that, the node title field would always report a wrong value for its length (since it's not read from the database).

  public function validateForm(array &$form, FormStateInterface $form_state) {
    parent::validateForm($form, $form_state);
    // Validate form input.
    $values = $form_state->getValues();
    if (!is_numeric($values['title_length'])) {
      $form_state->setErrorByName('title_length', $this->t('This should be a number!'));
    }

  }

The validation handler doesn't correctly validate the title length, as it would accept negative numbers, 0, and values that are too high for the database engine. For example, in MySQL 5.0.2 (and earlier versions) a VARCHAR field cannot have more than 255 characters, while in MySQL 5.0.3 and later versions, it can have up to 65,535 characters. Other database engines could have other limits the module is not applying.

PAReview is working again.

Looks good to me! Any reason why you only support the node entity type? Config schema is missing for your entity_title_length.config.

An automated phpunit test would be nice to ensure this works as designed. All minor things, no blockers.

Thank you for your contribution! I am going to update your account.

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• Dries' post on Responsible maintainers
• Best practices for creating and maintaining projects
• Maintaining a drupal.org project with Git
• Commit messages - providing history and credit
• Release naming conventions.
• Helping maintainers in the issue queues

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