report clj build failures to stderr

[bendlas]

The default behavior of clojure to write error reports into /tmp/clojure-*.edn doesn't really work well in a nix builder: After the build concludes, the edn file is deleted, or rather, it never hit the disk because in the build sandbox, a fresh tmpfs is mounted on /tmp.

So it's better, to restore the old behavior and let clojure barf to stderr. Nix will keep it available via nix log.

Before

😨 😢

       > Full report at:
       > /tmp/clojure-17334729123361555966.edn
       For full logs, run 'nix log /nix/store/2xzw9b0jmlhwzwidqzgw6mcllqhn4i5d-directory-DEV.drv'.

After

👍 😁

       > Execution error (NullPointerException) at rewrite-clj.custom-zipper.core/node (core.cljc:55).
       > Cannot invoke "clojure.lang.IFn.invoke(Object)" because "loc" is null
       >
       For full logs, run 'nix log /nix/store/qfigggf1jd6396zp5bjwiphnjwk1wlvz-directory-DEV.drv'.

[jlesquembre]

Thanks! It was annoying me too.

BTW, are you having issues with rewrite-clj? clj-nix expands all :git/sha hashes to avoid network requests, it seems like the error is originating from there.

[bendlas]

BTW, are you having issues with rewrite-clj?

Nah, all good. For testing the error reporting, I put some random characters before the (ns) clause, which happens to trip cljnix.builder_cli$check_main_class in rewrite-clj, where it attempts to parse the (ns) clause ...