edlp_d8/sites/all/modules/contrib/dev/devel/devel_generate/devel_generate.module

<?php

use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Field\FieldDefinitionInterface;
use Drupal\comment\Plugin\Field\FieldType\CommentItemInterface;
use Drupal\Component\Utility\Random;
use Drupal\devel_generate\DevelGenerateBase;
use Drupal\node\NodeInterface;

/**
 * Implements hook_menu_links_discovered_alter().
 */
function devel_generate_menu_links_discovered_alter(&$links) {
  $devel_generate_plugins = $devel_generate_manager = \Drupal::service('plugin.manager.develgenerate')->getDefinitions();
  foreach ($devel_generate_plugins as $id => $plugin) {
    $label = $plugin['label'];
    $links["devel_generate.$id"] = array(
      'title' => "Generate $label",
      'parent' => 'system.admin_config_development',
      'description' => $plugin['description'],
      'route_name' => "devel_generate.$id",
    );
  }
}

/**
 * Implements hook_entity_insert().
 *
 * Inserts nodes properly based on generation options.
 *
 * @param \Drupal\Core\Entity\EntityInterface $entity
 *  The base node created on submit. Inspects $node->devel_generate.
 */
function devel_generate_entity_insert(EntityInterface $entity) {
  if ($entity->getEntityTypeId() != 'node' || !isset($entity->devel_generate)) {
    return;
  }
  /** @var \Drupal\node\NodeInterface $entity */
  $results = $entity->devel_generate;

  if (!empty($results['max_comments'])) {
    foreach ($entity->getFieldDefinitions() as $field_name => $field_definition) {
      if ($field_definition->getType() == 'comment' && $entity->get($field_name)->status == CommentItemInterface::OPEN) {
        // Add comments for each comment field on entity.
        devel_generate_add_comments($entity, $field_definition, $results['users'], $results['max_comments'], $results['title_length']);
      }
    }
  }

  // Add an url alias. Cannot happen before save because we don't know the nid.
  if (!empty($results['add_alias'])) {
    $path = array(
      'source' => '/node/' . $entity->id(),
      'alias' => '/node-' . $entity->id() . '-' . $entity->bundle(),
    );
    \Drupal::service('path.alias_storage')->save($path['source'], $path['alias']);
  }

  // Add node statistics.
  if (!empty($results['add_statistics']) && \Drupal::moduleHandler()->moduleExists('statistics')) {
    devel_generate_add_statistics($entity);
  }
}

/**
 * Create comments and add them to a node.
 *
 * @param \Drupal\node\NodeInterface $node
 *   Node to add comments to.
 * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
 *   The field storage definition.
 * @param array $users
 *   Array of users to assign comment authors.
 * @param int $max_comments
 *   Max number of comments to generate per node.
 * @param int $title_length
 *   Max length of the title of the comments.
 */
function devel_generate_add_comments(NodeInterface $node, FieldDefinitionInterface $field_definition, $users, $max_comments, $title_length = 8) {
  $parents = array();
  $field_name = $field_definition->getName();
  $num_comments = mt_rand(1, $max_comments);
  for ($i = 1; $i <= $num_comments; $i++) {
    switch ($i % 3) {
      case 0:
        // No parent.
      case 1:
        // Top level parent.
        $parents = \Drupal::entityQuery('comment')
          ->condition('pid', 0)
          ->condition('entity_id', $node->id())
          ->condition('entity_type', 'node')
          ->condition('field_name', $field_name)
          ->range(0, 1)
          ->execute();
        break;
      case 2:
        // Non top level parent.
        $parents = \Drupal::entityQuery('comment')
          ->condition('pid', 0, '>')
          ->condition('entity_id', $node->id())
          ->condition('entity_type', 'node')
          ->condition('field_name', $field_name)
          ->range(0, 1)
          ->execute();
        break;
    }
    $random = new Random();
    $stub = array(
      'entity_type' => $node->getEntityTypeId(),
      'entity_id' => $node->id(),
      'field_name' => $field_name,
      'name' => 'devel generate',
      'mail' => 'devel_generate@example.com',
      'timestamp' => mt_rand($node->getCreatedTime(), REQUEST_TIME),
      'subject' => substr($random->sentences(mt_rand(2, $title_length), TRUE), 0, 63),
      'uid' => $users[array_rand($users)],
      'langcode' => $node->language()->getId(),
    );
    if ($parents) {
      $stub['pid'] = current($parents);
    }
    $comment = entity_create('comment', $stub);

    //Populate all core fields on behalf of field.module
    DevelGenerateBase::populateFields($comment);
    $comment->save();
  }
}

/**
 * Generate statistics information for a node.
 *
 * @param \Drupal\node\NodeInterface $node
 *   A node object.
 */
function devel_generate_add_statistics(NodeInterface $node) {
  $statistic = array(
    'nid' => $node->id(),
    'totalcount' => mt_rand(0, 500),
    'timestamp' => REQUEST_TIME - mt_rand(0, $node->getCreatedTime()),
  );
  $statistic['daycount'] = mt_rand(0, $statistic['totalcount']);
  db_insert('node_counter')->fields($statistic)->execute();
}