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perlcpan

What does the command "cpan reports" do exactly?

I tried to install Moose in perl 5.32.0 with the command cpan install Moose. The installation failed, with the following message:

Result: FAIL
Failed 448/478 test programs. 12/30 subtests failed.
Makefile:2047: recipe for target 'test_dynamic' failed
make: *** [test_dynamic] Error 255
  ETHER/Moose-2.2013.tar.gz
13 dependencies missing (Class::Load,Class::Load::XS,Data::OptList,Devel::OverloadInfo,Dist::CheckConflicts,Module::Runtime::Conflicts,Package::DeprecationManager,Package::Stash,Package::Stash::XS,Params::Util,Sub::Exporter,Sub::Identify,Test::CleanNamespaces); additionally test harness failed
  /usr/bin/make test -- NOT OK
//hint// to see the cpan-testers results for installing this module, try:
  reports ETHER/Moose-2.2013.tar.gz

I tried the command cpan reports ETHER/Moose-2.2013.tar.gz, and somehow this installed Moose correctly. What happened here? What does cpan reports do exactly? Is this the same as App::cpanreports?

Solution

  • [You asked why using cpan reports ... instead of cpan install ... helped. This answers that. brian d foy's explains why cpan reports ... wasn't what you wanted to execute.]

    It tries to install a module named reports.

    The syntax for cpan is

    cpan [options] <module_name> [<module_name> ...]

    The operation is specified through options. The default operator is -i (install).

    cpan install Moose

    This command tries to install two distributions:

    • The newest one containing the module install.

      A dummy module by this name was created, so this should not produce any errors.

      Newer versions of cpan simply ignore this erroneous request.

    • The newest one containing the module Moose.

      This is currently ETHER/Moose-2.2013.tar.gz.

    cpan reports ETHER/Moose-2.2013.tar.gz

    This command tries to install two distributions:

    • The newest one containing the module reports.

      There's no module named reports, so that part fails.

      >(error): Could not expand [reports]. Check the module name.
>(info): I can suggest names if you install one of Text::Levenshtein::XS, Text::Levenshtein::Damerau::XS, Text::Levenshtein, and Text::Levenshtein::Damerau::PP
>(info): and you provide the -x option on invocation.
>(error): Skipping reports because I couldn't find a matching namespace.

    • ETHER/Moose-2.2013.tar.gz

    So,

    cpan install Moose

    is merely a bad way of writing

    cpan Moose

    Also,

    cpan reports ETHER/Moose-2.2013.tar.gz

    is merely a bad way of writing

    cpan ETHER/Moose-2.2013.tar.gz

    Currently, this should currently be equivalent to

    cpan Moose

    In other words, there's no difference between the command you claimed didn't work and the one you claimed worked.