[META] List of bugs and typos in Drupal core found by Spleshka

Hi,
I looked up through all Drupal 7(8) core files and found a list of bugs and typos:

1. drupal_valid_path() has undefined variable $form_item.

2. In _theme_table_cell() in case when $cell is not an array variable $attributes might be undefined.

3. In update_fix_d7_install_profile() variable $file is undefined and unnecessary incorrect: See #1479572-5: Fix undefined variable error in update_fix_d7_install_profile().

4. Updater::prepareInstallDirectory has undefined $install_location.

5. Updater::update calls Updater::makeBackup() function with 2 arguments but it requires three.

6. In drupal_var_export() is a concatination to undefined variable $output in this case:

  elseif (is_object($var) && get_class($var) === 'stdClass') {
    // var_export() will export stdClass objects using an undefined
    // magic method __set_state() leaving the export broken. This
    // workaround avoids this by casting the object as an array for
    // export and casting it back to an object when evaluated.
    $output .= '(object) ' . drupal_var_export((array) $var, $prefix);
  }

7. In DatabaseStatementPrefetch::current PHP function array_unshift() are used incorrectly (required second parameter is missing):

case PDO::FETCH_CLASS | PDO::FETCH_CLASSTYPE:
  $class_name = array_unshift($this->currentRow);

And the second bug here. Variable $k is undefined:

case PDO::FETCH_COLUMN:
  if (isset($this->columnNames[$this->fetchOptions['column']])) {
    return $this->currentRow[$k][$this->columnNames[$this->fetchOptions['column']]];
  }
  else {
    return;
  }

8. In field_sql_storage_field_storage_query() variables $select_query and $field_base_table are undefined in this case:

if ($key) {
  $select_query->join($tablename, $table_alias, "$table_alias.entity_type = $field_base_table.entity_type AND $table_alias.$id_key = $field_base_table.$id_key");
    }

Edit by chx: this is a loop over a list (array with int keys starting from 0) and the !$key case will always come first which defines these variables.

9. In field_test_field_attach_delete_bundle() variable $bundle_old is undefined.

10. hook_field_delete() and hook_field_delete_revision() has wrong example of API usage: function file_field_delete_file() takes at least 4 arguments, but in documentation of this hooks file_field_delete_file() takes only 2 arguments.

11. In image_effect_definitions() I'm not sure that $cache->data is ready to check in the if clause:
if ($cache = cache_get("image_effects:$langcode") && !empty($cache->data)) {
$effects = $cache->data;
}

12. In documentation of hook_node_grants_alter() variable $user is undefined.

13. In documentation of hook_prepare() function file_check_upload() are deprecated since Drupal 6. Variable $field_name is undefined. Function _image_build_derivatives() is deprecated since Drupal 7.

14. In search_index() in case when $tag is FALSE variable $linktitle is undefined.

#1: #876580: drupal_valid_path fails for dynamic paths (e.g. user/% cannot be added to menus)
#2: -- (looks fine to Droplet, see comment #7)
#3: #1479572: Fix undefined variable error in update_fix_d7_install_profile()
#4: #1423510: Undefined var in prepareInstallDirectory
#5: #1476804: Updater::update calls Updater::makeBackup() function with 2 arguments but it requires three
#6: #1476776: drupal_var_export() is a concatenation to undefined variable $output
#7: #1476782: DatabaseStatementPrefetch::current PHP function array_unshift() are used incorrectly
#8: FIXED (see above chx's comment)
#9: -- (needs work)
#10: #1476812: hooks file_field_delete_file() takes only 2 arguments
#11: #1469758: Define $user in hook_node_grants_alter
#12: #1469758: Define $user in hook_node_grants_alter
#13: -- (needs work)
#14: #1479618: $linktitle is undefined in search_index()