Misclassification of java interoperability as function

[wardle]

When mapping using an anonymous fn to use java interop, splint says 'No need to wrap function. Clojure supports first-class functions', but you generally cannot unwrap in this case. e.g. (map #(Integer/parseInt %) ["1" "2" "3"])

PS. Thank you very much for this linter - really brilliant at identifying style improvements - particularly those where I can vastly simplify code such as preferring or etc. Thank you!

[wardle]

The only method I could think of to do this without running code, and only using structure, would be to look either for (. - which is obviously interop, or ([A-Z] ie a call to a static method on a class so will be capitalised.

[NoahTheDuke]

Thanks for trying it out! I'm glad it's proving helpful.

This is an interesting one, and I think you have the solution right. I would rather be silent for potential matches than warn on valid usage. Clojure can allow for some wacky constructions so it's better to play it safe.

PR is welcome, if you wanna try your hand at tackling it. I haven't written any documentation for how the pattern matching works or how the rules are defined, lol, but that makes it more fun, right?

[wardle]

Thanks @NoahTheDuke - I'll have a look - will be interesting!

[NoahTheDuke]

I've written a bunch of documentation about how the pattern DSL and rules objects are built, if you're still interested: https://cljdoc.org/d/io.github.noahtheduke/splint/1.1.1/doc/rules

[wardle]

I'll have a look. Thanks!

[wardle]

I looked at this but it is tricky. The rough heuristic above with a dot might work for some cases, but it doesn't catch the use of static methods on a Java class.

[NoahTheDuke]

Yeah, that's definitely an issue. Without deeper analysis (like clj-kondo does), I suspect there's not much we can do.

Maybe we could use the list of built-in classes that Clojure recognizes and extract the :use symbols and check against those? That would cover the majority of cases I expect. That'll be a lot harder than a simple check against capital letters tho.