[Pkg-rust-maintainers] Bug#1131090: rust-subunit - autopkgtest failure

[Peter Green]

Package: rust-subunit
Version: 0.3.0-1
Severity: serious

rust-subunit's autopkgtest fails because the code enabled by the "v1" feature
fails to build if the sync feature is not also enabled.

I see three possible ways forward.

1. Make the "v1" feature
2. Add additional conditionals to disable the "sync" parts of the "v1" code
    if the sync feature is not enabled.
3. Declare that using the "v1" feature without the "sync" feature is
    unsupported and set test_is_broken.

I feel others are likely better placed than me to decide which of these
is most appropriate.