How do I get a MakeMaker target for code coverage?

Question

In my ExtUtils::MakeMaker based project, I want to generate a code coverage report from my tests. I use Devel::Cover for that, but I have to run it manually:

HARNESS_PERL_SWITCHES=-MDevel::Cover make test && cover

That's too much to type (and remember), so I'd like to run something like make cover instead. ExtUtils::MakeMaker::Coverage seems to do that, but I cannot install it.

~/pl$ sudo cpan install ExtUtils::MakeMaker::Coverage
Loading internal logger. Log::Log4perl recommended for better logging
Reading '/Users/rwenner/.cpan/Metadata'
Database was generated on Thu, 08 Oct 2020 22:56:18 GMT
>(error): Could not expand [ExtUtils::MakeMaker::Coverage]. 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 ExtUtils::MakeMaker::Coverage because I couldn't find a matching namespace.

Why is that and how can I install that module? I can install other modules with cpan just fine, so I don't think it's a network issue.

Or is ExtUtils::MakeMaker::Coverage outdated (looks like the last update is from 2005)? What should I use instead?

Answer 1

Add a postamble to your Makefile.PL:

# Makefile.PL
use ExtUtils::MakeMaker;
WriteMakefile(...);

# specify additional testing targets
package MY;
sub MY::postamble {
    return q~
cover :: pure_all
    HARNESS_PERL_SWITCHES=-MDevel::Cover make test && cover

    ~;
}

This will add a target that will execute your desired command when you run make cover.