Code enhancement: Explicit join check in ensure_path

I think this is right.

Hi,
This patch breaks my views handler.
I define new views_handler_field:

class views_handler_video_thumbnails extends views_handler_field {
  /**
   * Aditional fields to query is added here. This fields are used to generate output.
   */
  function construct() {
    parent::construct();
    $this->additional_fields['nid'] = array('table' => 'node', 'field' => 'nid');
    $this->additional_fields['title'] = array('table' => 'node', 'field' => 'title');
    $this->additional_fields['converted'] = array('table' => 'node', 'field' => 'converted');
    $this->additional_fields['width'] = array('table' => KLIPPS_THUMBNAILS_SIZES_TABLE, 'field' => 'width');
    $this->additional_fields['height'] = array('table' => KLIPPS_THUMBNAILS_SIZES_TABLE, 'field' => 'height');
  }


  /**
   * Add option for thumbnail field in the Views admin UI.
   */
  function option_definition() {
    $options = parent::option_definition();
    $options['type']['sizes'] = variable_get('klipps_thumbnails_default_size', 0);
    return $options;
  }

  /**
   * Options form definition for the Views admin UI.
   *
   * @param $form
   * Form reference.
   *
   * @param $form_state
   * Reference to the array of the form data.
   */
  function options_form(&$form, &$form_state) {
    parent::options_form($form, $form_state);

    $form['type'] = array(
      '#type' => 'fieldset',
      '#collapsible' => FALSE,
      '#title' => t('Thumbnail type'),
      '#description' => t('Select the avaliable thumbnail size.'),
      '#weight' => -10,
      '#tree' => TRUE,
    );

    $info = _klipps_thumbnails_select_all_sizes();
    $options = array();
    if (!empty($info)) {
      foreach ($info as $value) {
        $options[$value['sid']] = $value['title'] . ' ('. $value['width'] .'x'. $value['height'] .')';
      }
    }
    $form['type']['sizes'] = array(
      '#title' => t('Result type'),
      '#type' => 'select',
      '#options' => $options,
      '#default_value' => $this->options['type']['sizes'],
    );
  }


  /**
   * Render thumbnail in the view.
   *
   * @param $values
   * View item which contains thumbnail.
   */
  function render($values) {
    $nid = $values->{$this->aliases['nid']};
    $converted = $values->{$this->aliases['converted']};
    $movie_title = $values->{$this->aliases['title']};
    $show_link = TRUE;
    if ( 0 == $converted ) {
      $show_link = FALSE;
    }
    // Get thumbnail
    $thumbnail = new stdClass();
    $thumbnail->filepath = $values->{$this->field_alias};
    $thumbnail->width = $values->{$this->aliases['width']};
    $thumbnail->height = $values->{$this->aliases['height']};

    $thumbnail_html = theme( "klipps_thumbnails_thumbnail", $thumbnail, $movie_title, $movie_title);


    //Generate link to the movie
    if ($show_link) {
      $options = array( 'html' => TRUE);
      $thumbnail_html = l($thumbnail_html, drupal_get_path_alias('node/'. $nid), $options);
    }
    //return "<div class='thumbnail-wrapper' style='width:". $thumb_size['thumb_width'] ."px;height: ". $thumb_size['thumb_height'] ."px;'>". $thumbnail_html .'</div>';
    return $thumbnail_html;
  }

  /**
   * Ensure the main table for this handler is in the query. We do somewhat
   * debauched things here to allow separate copies of the table to be added
   * for each instance of this field.
   */
  function ensure_my_table() {
    if (!isset($this->table_alias)) {
      //Add thumbnails table
      $join_extra[] = array('field' => 'sid', 'value' => $this->options['type']['sizes'], 'numeric' => TRUE);
      $alias = $this->table;
      $alias .= '_'. $this->options['type']['sizes'];

      if (empty($alias)) {
        $alias = NULL;
      }

      $join = new views_join();
      $join->construct($this->table, 'movie_upload', 'fid', 'fid', $join_extra);


      if ($table_alias = $this->query->add_table($this->table, $this->relationship, $join, $alias)) {
        if ($table_alias === TRUE) {
          $this->table_alias = $alias;
        }
        else {
          $this->table_alias = $table_alias;
        }
      }
      //Add thumbnail sizes table
      $alias_size = KLIPPS_THUMBNAILS_SIZES_TABLE;
      $alias_size .= '_'. $this->options['type']['sizes'];
      $join = new views_join();
      $join->construct(KLIPPS_THUMBNAILS_SIZES_TABLE, $this->table_alias, 'sid', 'sid');
      $this->query->add_table(KLIPPS_THUMBNAILS_SIZES_TABLE, NULL, $join, $alias_size);
    }
    return $this->table_alias;
  }
}

I use this handler on Attachment View.
Without this patch View build this query:

SELECT klipps_categories.k_cid AS k_cid,
   thumbnails_1.filepath AS thumbnails_1_filepath,
   node.nid AS node_nid,
   node.title AS node_title,
   node.converted AS node_converted,
   thumbnail_sizes_1.width AS thumbnail_sizes_1_width,
   thumbnail_sizes_1.height AS thumbnail_sizes_1_height,
   users.name AS users_name,
   users.uid AS users_uid,
   klipps_statistics.weekcount AS klipps_statistics_weekcount
 FROM klipps_categories klipps_categories 
 LEFT JOIN klipps_categories_node klipps_categories_node ON klipps_categories.k_cid = klipps_categories_node.k_cid
 LEFT JOIN node node ON klipps_categories_node.nid = node.nid
 LEFT JOIN movie_upload movie_upload ON node.nid = movie_upload.nid
 LEFT JOIN thumbnails thumbnails_1 ON movie_upload.fid = thumbnails_1.fid AND thumbnails_1.sid = 1
 LEFT JOIN thumbnail_sizes thumbnail_sizes_1 ON thumbnails_1.sid = thumbnail_sizes_1.sid
 INNER JOIN users users ON node.uid = users.uid
 LEFT JOIN klipps_statistics klipps_statistics ON node.nid = klipps_statistics.nid
 WHERE (node.type in ('movie')) AND (node.converted <> 0) AND (node.status <> 0) AND (klipps_categories.k_cid = 4)
   ORDER BY klipps_statistics_weekcount DESC

After implementing patch :

SELECT klipps_categories.k_cid AS k_cid,
   thumbnails_1.filepath AS thumbnails_1_filepath,
   node.nid AS node_nid,
   node.title AS node_title,
   node.converted AS node_converted,
   width,
   height,
   users.name AS users_name,
   users.uid AS users_uid,
   node.created AS node_created
 FROM klipps_categories klipps_categories 
 LEFT JOIN klipps_categories_node klipps_categories_node ON klipps_categories.k_cid = klipps_categories_node.k_cid
 LEFT JOIN node node ON klipps_categories_node.nid = node.nid
 LEFT JOIN movie_upload movie_upload ON node.nid = movie_upload.nid
 LEFT JOIN thumbnails thumbnails_1 ON movie_upload.fid = thumbnails_1.fid AND thumbnails_1.sid = 1
 INNER JOIN users users ON node.uid = users.uid
 WHERE (node.type in ('movie')) AND (node.converted <> 0) AND (node.status <> 0) AND (klipps_categories.k_cid = 3)
   ORDER BY node_created DESC

One join statement is missing:

LEFT JOIN thumbnail_sizes thumbnail_sizes_1 ON thumbnails_1.sid = thumbnail_sizes_1.sid

and two unknown fields in SELECT phase: width and height.

P.S. In Page View this handler works fine.

This is too complex for me to understand what's going on here. Also not a patch so 'needs review' is the wrong status.

Given the age of this issue, I have hope that it's resolved or no longer relevant.