EntityForm::buildForm

public EntityForm::buildForm(array $form, FormStateInterface $form_state)

public function buildForm(array $form, FormStateInterface $form_state) {
  // During the initial form build, add this form object to the form state and
  // allow for initial preparation before form building and processing.
  if (!$form_state->has('entity_form_initialized')) {
    $this->init($form_state);
  }

  // Ensure that edit forms have the correct cacheability metadata so they can
  // be cached.
  if (!$this->entity->isNew()) {
    \Drupal::service('renderer')->addCacheableDependency($form, $this->entity);
  }

  // Retrieve the form array using the possibly updated entity in form state.
  $form = $this->form($form, $form_state);

  // Retrieve and add the form actions array.
  $actions = $this->actionsElement($form, $form_state);
  if (!empty($actions)) {
    $form['actions'] = $actions;
  }

  return $form;
}