Inaccurate doxygen for \Drupal\Core\Database\Query\ConditionInterface::condition

Seems like the parameters should be ignored in a different way. $value parameter expects NULL value while $field accepts empty string. Is there something special about this?

https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Database%...

/**
 * {@inheritdoc}
 */
public function isNull($field) {
  return $this->condition($field, NULL, 'IS NULL');
}

/**
 * {@inheritdoc}
 */
public function isNotNull($field) {
  return $this->condition($field, NULL, 'IS NOT NULL');
}

/**
 * {@inheritdoc}
 */
public function exists(SelectInterface $select) {
  return $this->condition('', $select, 'EXISTS');
}

/**
 * {@inheritdoc}
 */
public function notExists(SelectInterface $select) {
  return $this->condition('', $select, 'NOT EXISTS');
}

Anyway this documentation edition is correct.

1. +++ b/core/lib/Drupal/Core/Database/Query/ConditionInterface.php
   @@ -49,7 +49,9 @@
   +   *   and the value should be a SelectInterface object.
   

   $value I think?

2. +++ b/core/lib/Drupal/Core/Database/Query/ConditionInterface.php
   @@ -59,6 +61,9 @@
   +   * @throws \Drupal\Core\Database\InvalidQueryException
   +   *   If passed invalid arguments.
   

   This doesn't really provide that much info. The exception seems to be thrown when $value is an empty array. It is a bit of a funny exception...

I was able complete #4-1 part, hope this works.

Nice work! I mentored @AbhishekLal on IRC with this one. I am setting this back to Needs work for #4-2.

Looks good to me and all of @alexpott issues are fixed.

Committed/pushed to 8.3.x, thanks!