phacility/phabricator · critical · Exception

This revision has no diffs. Something has gone quite wrong.

Error message

This revision has no diffs. Something has gone quite wrong.

What it means

A revision page requires at least one diff; the controller throws this invariant error when a DifferentialRevision row exists with zero attached diffs. Normal Phabricator flows always create revisions together with a first diff, so this error signals damaged or abnormal data.

Source

Thrown at src/applications/differential/controller/DifferentialRevisionViewController.php:67

    $revision = id(new DifferentialRevisionQuery())
      ->withIDs(array($this->revisionID))
      ->setViewer($viewer)
      ->needReviewers(true)
      ->needReviewerAuthority(true)
      ->needCommitPHIDs(true)
      ->executeOne();
    if (!$revision) {
      return new Aphront404Response();
    }

    $diffs = id(new DifferentialDiffQuery())
      ->setViewer($viewer)
      ->withRevisionIDs(array($this->revisionID))
      ->execute();
    $diffs = array_reverse($diffs, $preserve_keys = true);

    if (!$diffs) {
      throw new Exception(
        pht('This revision has no diffs. Something has gone quite wrong.'));
    }

    $revision->attachActiveDiff(last($diffs));

    $diff_vs = $this->getOldDiffID($revision, $diffs);
    if ($diff_vs instanceof AphrontResponse) {
      return $diff_vs;
    }

    $target_id = $this->getNewDiffID($revision, $diffs);
    if ($target_id instanceof AphrontResponse) {
      return $target_id;
    }

    $target = $diffs[$target_id];

    $target_manual = $target;

View on GitHub (pinned to 5720a38cfe)

Solutions

  1. Create revisions through the API or UI (differential.creatediff plus differential.updaterevision) so every revision gets at least one diff.
  2. Repair the data: attach a diff to the revision or remove the empty revision row.
  3. Restore from backups if the diffs were lost accidentally.
Defensive patterns

Strategy: try-catch

Try / catch

try {
  // render or operate on the revision
} catch (Exception $ex) {
  if (preg_match('/has no diffs/', $ex->getMessage())) {
    // data integrity violation: quarantine the revision and alert the admin
  } else {
    throw $ex;
  }
}

Prevention

When it happens

Trigger: Opening a revision whose diffs were all deleted or never created: revisions inserted directly into the database, partial creation failures, or cleanup scripts that removed diffs without the revision.

Common situations: Rows created by migration or seeding scripts that bypass the API; broken imports; database-level deletion of diffs that left empty revisions behind.

Related errors

AI-assisted analysis of phacility/phabricator@5720a38cfe (2026-08-21). Data as JSON: /api/errors/034dc4e01e46e546. Report an issue: GitHub.