Autogenerated Test Stubs

Sometimes getting test coverage where it ought to be can be a little tedious, at least with a highly dynamic language. I have an object containing constant data and synthetic attributes calculated from the constant data. It has about a dozen of these synthetic attributes:

has [ @plusses, @minuses ], is => 'ro', lazy_build => 1;

I use this skeleton for my testing code:

#! perl

use Modern::Perl;
use Test::More;
use lib 't/lib';

__PACKAGE__->main( 'Some::Module::To::Test' );

sub main
{
    my ($test, $module) = @_;
    use_ok( $module ) or exit;

    $test->test_some_feature( $module );
    $test->test_another_feature( $module );
    $test->test_still_another_feature( $module );
    $test->test_one_remaining_feature( $module );

    done_testing();
}

sub default_args
{
    my $self = shift;

    return
    (
        default => 'Value',
        for     => 'example',
        @_
    );
}

sub test_some_feature
{
    my ($test, $module) = @_;
    my $obj             = $module->new( $test->default_args );

    ...
}

Ultimately I should port these tests to Test::Class, but I don't quite need it yet. That does leave some repetition in typing the boilerplate code I need for each test method. If I were using an IDE which could resolve these method calls without having to run code, I'd let autocomplete generate this code for me.

It's only a couple of extra steps in Perl though:

sub AUTOLOAD
{
    (my $name = our $AUTOLOAD) =~ s/main:://;
    print STDERR <<END_HERE;
sub $name
{
    my (\$test, \$module) = \@_;
    my \$score           = \$module->new( \$test->default_args );
}

END_HERE
}

With that AUTOLOAD in place, I can run the test, redirect STDERR to a file, then insert the contents of that file in the test file itself. It's silly and it's simple, but it works.