The "test-phantoms" command:
Usage: fossil test-phantoms
Show all phantom artifacts. A phantom artifact is one for which there is no content. Options:
- --count
 - Show only a count of the number of phantoms.
 - --delta
 - Show all delta-phantoms. A delta-phantom is a artifact for which there is a delta but the delta source is a phantom.
 - --list
 - Just list the phantoms. Do not try to describe them.