Return a non-zero exit code when matches exist

[guilhermesimoes]

This is just to get the conversation started around some code to solve #34.

Just as an example, rails_best_practices returns the number of errors found as the exit code. But reek doesn't.
I don't feel strongly one way or the other. But if you're not using the exit codes for anything else, why not? It could be useful.

Also, should this really need a flag to work? Shouldn't this just be the default behavior of the executable?

[zenspider]

I'm all for the idea, but I hesitate to make it exit equal to the size / score / whatever. Some code bases are horrific. For example, ruby_parser currently scores 15589. :)

[zenspider]

That said, I'm not sure having a non-empty flay report is an error.

[guilhermesimoes]

Score of 15589? Ouch :P

I don't think a non-empty Flay report is an error either. However, non-zero exit codes can carry special meanings. In this case, it would be mostly useful in continuous integration to signal that some code duplication was found.

Though I must say, there is always some code duplication reported by Flay that you can't (or aren't supposed to) fix, like Rails' RESTful controllers. So if Flay's exit codes were either just 0 or 1, I believe they would be of limited use since Flay would return 1 most of the time.

[zenspider]

The more I think about this, the less I like it. Unix exit codes are normally reserved for reporting success or error conditions. Having a flay score is not an error. Not being able to parse something is an error. I'd rather flay report 1 if it can't parse than because there is code that should be reviewed and then potentially accepted as-is.

For example, you'd never want to see a team set up the following nightly cronjob:

flay lib &> flay.txt || mail -s "error in flay" team < flay.txt

It would simply be noise. Nor would you want a CI to report a failure based on a non-zero exit from flay.

As such, I don't see this really conveying the right type of information via exit code.

[guilhermesimoes]

I can see your point.

I think you should also close #34 then.