Multi-output package with pin_subpackage in test requirements fails to build

[gabuzi]

I have a situation where I build a multi output pkg from a monorepo.
Multiple subpackages with dependencies between them are built. "Normal" run dependencies work fine (I use pin_subpackage for this).

However, tests for one subpackage package require another subpackage. Using pin_subpackage for this works fine with conda-build, but rattler-build 0.28.0 doesn't seem to like this.

While we're at it: The situation I have also actually contains a dependency cycle (at test time only), and conda-build handles this. I'm just mentioning it here, because it seems like rattler-build seems to follow an eager testing schedule (test right after build), whereas conda first builds all subpackages, and then tests them. Rattler-build's eager testing behavior would not be compatible with this, unless the test-pins will be considered in the sorting of build steps (which can be a bit challenging given that it is in fact a cycle). With conda-build's build first, test later approach, this is no issue.

Reproducer:

recipe:
  name: subpkg_in_test_cyclic_dep
  version: 1234

source:
  path: .

build:
  number: 0

outputs:
  - package:
      name: subpkg1
    build:
      script:
        - touch file1
        - cp file1 $PREFIX/
    requirements:
      run:
        - ${{ pin_subpackage("subpkg2", exact=True) }}

  - package:
      name: subpkg2
    build:
      script:
        - touch file2
        - cp file2 $PREFIX/
    tests:
      - script:
          -
        requirements:
            run:
              - ${{ pin_subpackage("subpkg1", exact=True) }}  # <-- this causes issues

[wolfv]

Thanks! Yes, I was aware of the issues with eager testing and it's something I would like to address soon. I would like to sort packages to still test as early as possible just to make users detect issues early on.

[mgorny]

I've just had a similar problem, though there are no cycles in my case — just a plain case of:

recipe:
  name: test
  version: 1

outputs:
  - package:
      name: test
  - package:
      name: test-tests
    tests:
      - script:
          - true
        requirements:
          run:
            - ${{ pin_subpackage('test', exact=True) }}

causing:

thread 'main' panicked at src/lib.rs:415:55:
Could not parse MatchSpec: ParseChannelError(InvalidName("{\"pin_subpackage\":{\"name\""))
stack backtrace:
   0: rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::result::unwrap_failed
   3: rattler_build::can_test
   4: core::iter::traits::iterator::Iterator::partition
   5: rattler_build::run_build_from_args::{{closure}}
   6: rattler_build::main::{{closure}}
   7: tokio::runtime::park::CachedParkThread::block_on
   8: tokio::runtime::runtime::Runtime::block_on
   9: rattler_build::main
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

The specific use case is we're splitting torchvision's tests into a subpackage, so they wouldn't multiply the size of the main package. For the time being, I have worked around the problem by specifying the pinned subpackage as a regular run requirement in the *-tests subpackage.