New reverse-related checks

[vdichev]

New checks with reverse (ideas from https://pavelfatin.com/scala-collections-tips-and-tricks/):

• reverse.map can be rewritten as reverseMap
• reverse.iterator can be rewritten as reverseIterator
• reverse.take(n).reverse can be rewritten as takeRight(n)

[HairyFotr]

Looks good, I'll merge now... and I hope to take a closer look at the article in a few days - looks like it has plenty of possible static check ideas contained in it.

Thanks!

[vdichev]

Actually most of these have already been implemented! I might open an issue for a quick discussion on some low-hanging fruit from the article which might be a good idea to implement.

For this pull request I haven't changed the README, are the correct links to the appropriate line in the test generated?

I've also considered merging some checks, like reverse.{head,headOption,map,iterator} into one and then reverse.{head,take(n)}.reverse into one similarly to UseFuncNot{Fold,Reduce}. Not sure it's worth it though, what do you think?

[HairyFotr]

Firstly, sorry for the slow reply.

Yes, please open a new issue, and I'll try get through the article soon :)

The list is generated by the shell script printWarnings and copy pasted into the readme.

I'd prefer if the checks stay separate to enable more fine-grained control. If there's a request to have them joined, a feature for tagging/grouping checks could be implemented, which would also solve a few other popular requests (e.g. tagging checks as optimization / style / probable bug, or to skip slowest checks, or all checks on a certain compiler phase, etc.).

Btw, I've expanded these and some other checks to also include String (the AST is the same as for Array, just with "augmentString" instead of "arrayOps").

[vdichev]

Yes, the strings checks are useful.

I already have a few more checks implemented like using .head instead of seq(0) and not implementing headOption manually with an if statement.

What I was interested in is a place to discuss which checks are more appropriate to implement in terms of code style and weeding out the more controversial advise, and also which have a higher ratio of usefulness to false positives.

I'll submit my next pull request in the next couple of days and try with issues for the next checks.