Dancer fails to install with 'cpanm'

[jkeenan]

Today I attempted to install Dancer-1.3202 via cpanm on Linux x86_64 (Ubuntu 14.04 LTS) where my basic perl is 5.24.0.

cpanm Dancer

The installation failed due to multiple failures of Dancer's own tests. Here is the first such failure as reported in the build.log:

t/00_base/normalize_path.t .......................... ok
# Test::TCP 2.16 loaded successfully
# Test::More 1.001014 loaded successfully
# JSON 2.61 loaded successfully
# YAML 1.15 loaded successfully
# Clone 0.38 loaded successfully
# Plack 1.0039 loaded successfully
# XML::Simple 2.22 loaded successfully
# HTTP::Parser::XS 0.17 loaded successfully
t/00_base/optional-module-versions.t ................ ok
t/00_base/uri_for.t ................................. ok
core - serializer - JSON is needed and is not installed at /home/jkeenan/.cpanm/work/1467654616.24559/Dancer-1.3202/blib/lib/Dancer/Serializer.pm line 33.
# Looks like you planned 11 tests but ran 9.
# Looks like your test exited with 255 just after 9.
Recursive inheritance detected in package 'Types::Serialiser::BooleanBase' during global destruction.
t/01_config/01_settings.t ...........................
Dubious, test returned 22 (wstat 5632, 0x1600)
Failed 2/11 subtests

The string core - serializer - JSON is needed and is not installed appears repeatedly in the build.log. However, as you can see I do indeed have JSON available, which is confirmed by:

$ perldoc -l JSON
/home/jkeenan/perl5/perlbrew/perls/perl-5.24.0/lib/site_perl/5.24.0/JSON.pm

Can you diagnose?

Thank you very much.
Jim Keenan

[jkeenan]

I was subsequently able to install Dancer2 via cpanm. So while it would be good to diagnose this problem, my need is no longer urgent.