Weird testing error depending on the available testers

[JJ]

Refs: JJ/docker-raku-test#12 p6steve/raku-Physics-Constants#5

This is a weird error. zef test . works fine on the default installation, which uses the prove+ plugin:

===> Testing: JSON::Fast:ver<0.16>
[JSON::Fast] Testing with plugin: Zef::Service::Shell::prove+{<anon|1>}
[JSON::Fast] t/01-parse.t ...................... ok
[JSON::Fast] t/02-structure.t .................. ok
[JSON::Fast] t/03-unicode.t .................... ok
[JSON::Fast] t/04-roundtrip.t .................. ok
[JSON::Fast] t/05-unreasonable-requirements.t .. ok
[JSON::Fast] t/06-control-characters.t ......... ok
[JSON::Fast] t/07-datetime.t ................... ok
[JSON::Fast] t/08-sorted-keys.t ................ ok
[JSON::Fast] t/09-race.t ....................... ok
[JSON::Fast] t/10-multidocument.t .............. ok
[JSON::Fast] t/11-enum.t ....................... ok
[JSON::Fast] t/12-assocpositional.t ............ ok
[JSON::Fast] All tests successful.
[JSON::Fast] Files=12, Tests=546,  5 wallclock secs ( 0.05 usr  0.01 sys +  6.66 cusr  0.46 csys =  7.18 CPU)
[JSON::Fast] Result: PASS

However, it fails inmediately if you use TAP, which is what the test container uses:

/test $ zef --debug test .
===> Testing: JSON::Fast:ver<0.16>
[JSON::Fast] Testing with plugin: Zef::Service::TAP+{<anon|1>}
===> Testing [FAIL]: JSON::Fast:ver<0.16>
Aborting due to test failure: JSON::Fast:ver<0.16> (use --force-test to override)

I really have no idea why, or even where to start looking. It's not failing on other modules, just on this one.

[JJ]

Definitely nothing to do with this distro. Closing.