Add new Minitest/SkipWithoutReason cop

[fatkodima]

Closes #198.

I am thinking: do we need a config option to be able to always enforce skip with comments (no matter if in conditional or not)?

[koic]

I think this cop can be published without a config option first. How about a rule like the one below for conditions?

# bad
if condition
  do_something
  skip
end

# good
skip if condition

if condition
  skip
end

It is clear when the if body has a single sentence, but may be ambiguous when there are multiple sentences.

while is also ambiguous than if, so it may be bad.

# bad
do_something while condition

And It's a corner case, I think the following is also bad.

# bad
if condition
  skip
else
  skip
end

Can you add test cases and adjust the implementation?

[koic]

How about a name like SkipWithoutArgument, SkipWithoutMessageArgument, or SkipWithoutReason? Because "comment" might imagine source code comment.

[fatkodima]

@koic Changed the name and adjusted the logic accordingly to the comments.

[koic]

I tried running it with the rails/rails repo.

In the following, all when not use skip, only else uses skip. In other words, the reason for skip in else is derivable, so I think it can be allowed. e.g.:

          case connection.class::ADAPTER_NAME
          when "PostgreSQL"
            unless connection.instance_variable_get(:@raw_connection).transaction_status == ::PG::PQTRANS_INTRANS
              connection.instance_variable_get(:@raw_connection).async_exec("begin")
            end
            connection.instance_variable_get(:@raw_connection).async_exec("set idle_in_transaction_session_timeout = '10ms'")
            sleep 0.05
          when "Mysql2"
            connection.send(:internal_execute, "set @@wait_timeout=1")
            sleep 1.2
          else
            skip
          end

It also seems obvious to skip in case of an exception, so it seems that it can be also allowed. e.g.:

     begin
       @cache.delete_matched("*")
     rescue NotImplementedError
       skip
     end

@fatkodima Can you take a look at this?

[fatkodima]

@koic Updated with the suggested cases.

[fatkodima]

Thanks for another review! Added more suggested changes.

[koic]

Let's start with this behavior and adjust it according to feedback use cases. Thank you!