elixir 1.5.1 dialyzer_test.exs fails on GNU Guix

[pjotrp]

I am trying to update the installation of elixir 1.5.1 GNU Guix. The following dialyzer tests fail with

  1) test no warnings on with/else (Kernel.DialyzerTest)
     test/elixir/kernel/dialyzer_test.exs:108
     ** (File.CopyError) could not copy from "/tmp/guix-build-elixir-1.5.1.drv-0/elixir-1.5.1/lib/elixir/tmp/dialyzer/Elixir.Dialyzer.With.beam" to "/tmp/guix-build-elixir-1.5.1.drv-0/elixir-1.5.1/lib/elixir/tmp/dialyzer/line108/Elixir.Dialyzer.With.beam": no such file or directory
     code: copy_beam! context, Dialyzer.With
     stacktrace:
       (elixir) lib/file.ex:631: File.cp!/3
       test/elixir/kernel/dialyzer_test.exs:109: (test)



  2) test no warnings on for falsey check that always boolean (Kernel.DialyzerTest)
     test/elixir/kernel/dialyzer_test.exs:102
     ** (File.CopyError) could not copy from "/tmp/guix-build-elixir-1.5.1.drv-0/elixir-1.5.1/lib/elixir/tmp/dialyzer/Elixir.Dialyzer.ForBooleanCheck.beam" to "/tmp/guix-build-elixir-1.5.1.drv-0/elixir-1.5.1/lib/elixir/tmp/dialyzer/line102/Elixir.Dialyzer.ForBooleanCheck.beam": no such file or directory
     code: copy_beam! context, Dialyzer.ForBooleanCheck
     stacktrace:
       (elixir) lib/file.ex:631: File.cp!/3
       test/elixir/kernel/dialyzer_test.exs:103: (test)



  3) test no warnings on defmacrop (Kernel.DialyzerTest)
     test/elixir/kernel/dialyzer_test.exs:114
     ** (File.CopyError) could not copy from "/tmp/guix-build-elixir-1.5.1.drv-0/elixir-1.5.1/lib/elixir/tmp/dialyzer/Elixir.Dialyzer.Defmacrop.beam" to "/tmp/guix-build-elixir-1.5.1.drv-0/elixir-1.5.1/lib/elixir/tmp/dialyzer/line114/Elixir.Dialyzer.Defmacrop.beam": no such file or directory
     code: copy_beam! context, Dialyzer.Defmacrop
     stacktrace:
       (elixir) lib/file.ex:631: File.cp!/3
       test/elixir/kernel/dialyzer_test.exs:115: (test)

The GNU Guix build environment is restricted and I disabled these tests. Is there a way to fix them?

[josevalim]

In what ways GNU Guix is restricted? Some tests require us to work with temporary directories and if those are not available, disabling the tests is the way to go.

[pjotrp]

Restrictions apply to using files outside the build tree and there should be no outside network access. All with reproducibility in mind (deterministic builds). Creating files in the build tree should be OK.

Above tests want to copy to, for example,

lib/elixir/tmp/dialyzer/line114/Elixir.Dialyzer.Defmacrop.beam

The directory $src/lib/elixir/tmp does not exist at test time. Any idea why?

I have more failing tests, but would like to resolve them one by one. Or disable them, as you say, but I think we should only disable when there is no other way. Patches are hard to maintain. Note that Erlang has no patches against its source tree and tests in GNU Guix. It is possible. And getting it to work with Guix will make it bullet proof in other environments.

[josevalim]

@pjotrp sure. But how being unable to create a temporary directory is going to help us? A lot of our tests are asserting we are able to perform some operations against the file system. After all, we need to assert we can create directories, files, links, etc.

[pjotrp]

No worries, you can create temporary directories in the build tree. But not outside. What is not clear to me is how it is getting done in above case. I guess I have to dig a little deeper.

[josevalim]

@pjotrp thank you, I understand it now. I misread the original report, it seems it is trying to create something in /tmp, which we likely shouldn't do, instead of using a tmp inside the build tree. Please do investigate!

[pjotrp]

Actually the build system is in /tmp. It is not that bad. Looks like mkdir_p! misses out on creating the dir. I'll check why this is. Maybe it is a permission thing.

[pjotrp]

I am closing this issue because it is a Guix environment thing and I have trouble replicating it outside the Guix build system. I will look into it again and post a fix when there is one.