phacility/phabricator · error · Exception

Owner rule value must have only one elmement (value is "%s")

Error message

Owner rule value must have only one elmement (value is "%s").

What it means

Thrown by assertValidRuleRecordValue() for the 'task.owner' rule when the value list contains more than one entry. The rule models a single owner, so after the empty check it enforces count($value) == 1. (Upstream message contains the typo 'elmement'.) This is save-time validation via getRuleRecordValueValidationException().

Source

Thrown at src/applications/project/trigger/PhabricatorProjectTriggerManiphestOwnerRule.php:42

  protected function assertValidRuleRecordFormat($value) {
    if (!is_array($value)) {
      throw new Exception(
        pht(
          'Owner rule value should be a list, but is not (value is "%s").',
          phutil_describe_type($value)));
    }
  }

  protected function assertValidRuleRecordValue($value) {
    if (!$value) {
      throw new Exception(
        pht(
          'Owner rule value is required. Specify a user to assign tasks '.
          'to, or the token "none()" to unassign tasks.'));
    }

    if (count($value) > 1) {
      throw new Exception(
        pht(
          'Owner rule value must have only one elmement (value is "%s").',
          implode(', ', $value)));
    }

    $owner_phid = $this->convertTokenizerValueToOwner($value);
    if ($owner_phid !== null) {
      $user = id(new PhabricatorPeopleQuery())
        ->setViewer($this->getViewer())
        ->withPHIDs(array($owner_phid))
        ->executeOne();
      if (!$user) {
        throw new Exception(
          pht(
            'User PHID ("%s") is not a valid user.',
            $owner_phid));
      }
    }

View on GitHub (pinned to 5720a38cfe)

Solutions

1. Edit the trigger so the owner field contains exactly one entry: one user PHID or the token none().
2. Repair the stored record to a one-element array if the editor cannot open it.
3. Fix import/migration code to pick a single owner for task.owner rules (they cannot hold a list).
4. Split conflicting requirements into separate columns/triggers, since each drop applies one owner.

Example fix

// before
$value = array('PHID-USER-a', 'PHID-USER-b');

// after
$value = array('PHID-USER-a');

if (count($value) > 1) {
  throw new Exception('Owner rule accepts exactly one value; got '.count($value));
}

function isSingleOwnerValue($value) {
  return is_array($value) && count($value) === 1;
}

$ex = $rule->getRuleRecordValueValidationException();
if ($ex) { /* render message in editor; keep first value only */ }

When it happens

Trigger: A task.owner rule whose value array holds 2+ PHIDs, e.g. ['PHID-USER-a','PHID-USER-b'] — typically from a hand-edited record, an import script, or a client that reused an 'Add Projects' style value for the owner rule. Saving or re-validating the trigger throws.

Common situations: Copy-paste of an 'add projects' value shape into an owner rule; migration tooling that mapped a multi-owner field onto the single-owner rule; direct DB writes.

Related errors

• You must select at least one project tag to add.
• Owner rule value is required. Specify a user to assign tasks
• You must select at least one project tag to remove.
• Add project rule value should be a list, but is not (value i
• Owner rule value should be a list, but is not (value is "%s"

AI-assisted analysis of phacility/phabricator@5720a38cfe (2026-08-21). Data as JSON: /api/errors/f262aaaf3de374ac. Report an issue: GitHub.