t/formats.t fails on some of my systems --- probably if Time::Moment is not installed:
# Failed test 'assertion behaviour can be enabled later with an already-loaded schema'
# at t/formats.t line 235.
# Compared $data->{"errors"}[0]{"error"}
# got : 'cannot validate format "date-time": Can't locate Time/Moment.pm in @INC (you may need to install the Time::Moment module) (@INC contains: ... ) at /usr/home/cpansand/.cpan/build/2021081420/JSON-Schema-Modern-0.516-8/blib/lib/JSON/Schema/Modern/Vocabulary/FormatAssertion.pm line 152.
# '
# expect : 'not a date-time'
# Failed test 'valid assertion behaviour does not die'
# at t/formats.t line 251.
# Comparing hash keys of $data
# Extra: 'errors'
... (etc) ...
# '
# expect : 'not a date-time'
# Failed test 'valid assertion behaviour does not die'
# at t/formats.t line 274.
# Comparing hash keys of $data
# Extra: 'errors'
# Looks like you failed 4 tests of 5.
# Failed test 'toggle validate_formats after adding schema'
# at t/formats.t line 279.
# Looks like you failed 1 test of 6.
t/formats.t .............................
Dubious, test returned 1 (wstat 256, 0x100)
Failed 1/6 subtests
t/formats.t fails on some of my systems --- probably if Time::Moment is not installed: