Does method `computer_online_query` return only boolean?  Or does it return the results of a query?  The method name is conflicting with what I see going on in the test.

If it's simply testing whether it thinks it should be online or not, suggest changing the name to `computer_online?`.  The question mark is allowed in Ruby method names and strongly implies that it is a boolean query.  "Query" implies some kind of database-like query results; in this case it's superfluous (if I understand the code correctly).