Could not load serialization package: JSON : Can't locate JSON.pm in @INC (you may need to install the JSON module) (@INC contains: /__w/cache-fastmmap/cache-fastmmap/blib/lib /__w/cache-fastmmap/cache-fastmmap/blib/arch /usr/local/lib/perl5/site_perl/5.30.3/x86_64-linux-gnu /usr/local/lib/perl5/site_perl/5.30.3 /usr/local/lib/perl5/vendor_perl/5.30.3/x86_64-linux-gnu /usr/local/lib/perl5/vendor_perl/5.30.3 /usr/local/lib/perl5/5.30.3/x86_64-linux-gnu /usr/local/lib/perl5/5.30.3 .) at (eval 13) line 1.
# Looks like your test exited with 2 just after 2.
See full output: https://github.com/szabgab/cache-fastmmap/runs/1374034225?check_suite_focus=true
One solution would be to skip that specific test if JSON is not available.