Human-competitive Patches in Automatic Program Repair with Repairnator | Hacker News Reader

Human-competitive Patches in Automatic Program Repair with Repairnator

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40 pointsDotnaught7 comments

>June 25, 2018, https://github.com/donnelldebnam/CodeU-Spring-2018-29/pull/5... “Thanks!!”

A strange fix to equally strange code. In the old code `tags` wasn't used in the first place, and in the new code it's put inside a scope ensuring it definitely can't be used. Why not just delete it?

If it's being used just for side-effects in the `getAllHashtags()` call, why still bind it to a variable?

Edit: Also, it isn't consistent with the original code in that it prefixes the member access with `this.` whereas the old code didn't do that. If I were the bot's author I wouldn't consider this commit a particularly good example of the bot's capability...

The fixes as far as I can tell are pretty rudimentary, like if something is null and someone is trying to do something with it put an check for null around it. I would imagine if your used something like this consistently you code would become very much like a biological system -- a hack here a hack there... but hey it works.

I wonder if the Repairnator is in charge of writing its own commit comments (which I think is technically possible).

The simple NullPointerException fixes don't look very impressive, although understandably still quite awesome for a bot.

On the other hand, its commit on the eclipse/ditto repo was pretty interesting: https://github.com/eclipse/ditto/pull/151/commits/7ab96e373e... I'm quite surprised how it determined the usage of a function it did not write.

I spent last year attempting something very similar in Python (www.duckly.com - unlaunched) and am very impressed. It's an extremely difficult problem and the CI data angle is inspired.

How does the actual "repairing" part work? Looks like it relies on a few external libraries and also includes custom code for dealing with NullPointerExceptions (which seem to be what was showcased here)

- https://github.com/Spirals-Team/repairnator/tree/master/repa...

- https://github.com/SpoonLabs/nopol

- https://github.com/SpoonLabs/astor

Interesting idea, though the examples given were mainly fixing Null Pointer Exceptions, which can be somewhat solved with static analysis in languages without nullability.

Url changed from https://www.theregister.co.uk/2018/10/17/luc_escape_bug_fixe..., which points to this.

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