The statistician George Box is often quoted as saying: "All models are flawed, but some models are useful". I'm well aware that the assumption regarding testers being representative of the broader userbase isn't exactly correct. But I'm curious if the estimate is off by a little bit, or a lot.

Based on the types of questions seen on various forums, there could be many more Windows users than the testing logs would suggest. And if that is the case, I'd like to devote some time to testing on Windows.

Just to get you started, a list of dists with failures on the Windows platform in cpantesters within the last month.

#!/usr/bin/perl
use strict;
use warnings;
use feature 'say';
use DateTime;
use Mojo::UserAgent;

# http://api.cpantesters.org/docs/?url=/v3#!/Summary/v3_summary_all 
my $url = 'http://api.cpantesters.org/v3/summary';

# just an example, the last month
my $date = DateTime->now->add( months => -1 )->iso8601.'Z';
my $osname = 'mswin32';
my $grade = 'fail';

my $ua = Mojo::UserAgent->new;
my $res = $ua->get( "$url?osname=$osname&grade=$grade&since=$date" )->
+res->json; 
say "$osname $grade since $date";
foreach my $fail ( @{$res} ){
    say "$fail->{dist} failed on $fail->{perl}";
}
[download]

Displays:

mswin32 fail since 2020-01-19T16:45:05Z
Config-Registry failed on 5.20.1
ExtUtils-MakeMaker failed on 5.22.1
Config-Registry failed on 5.18.2
Config-Registry failed on 5.18.2
CBOR-Free failed on 5.18.2
MySQL-ORM failed on 5.18.2
MySQL-ORM failed on 5.12.2
Metabolomics-Fragment-Annotation failed on 5.18.2
MySQL-ORM failed on 5.20.1
Config-Registry failed on 5.12.2
Class-Refresh failed on 5.18.2
.....
[download]

Many thanks! I greatly appreciate that help!

I don't think there is going to be a method to determine the number of users accurately. Anyone running cpan/cpanm can configure their client to report the installation status (pass/fail) to cpantesters. If you care enough and have the means you could setup an automatic smoker to do this without manual intervention.

I would greatly appreciate knowing how to get cpanm to report install pass/fails.

a windows user

Windows has licence costs.

Could useful results be obtained by running Strawberry Perl or Cygwin perl on Wine on a Linux or BSD host? Or perhaps using ReactOS? Or should those be more properly considered different platforms from "proper" cygwin and mswin32?

the Wine comparability layer could IMHO introduce problems. I think this sort of thing would simply muddy the waters.

Yes, but it might also be something worth smoking.

Perl itself has failing tests (for me) when installing in Ubuntu 18.04.2 LTS over Windows Subsystem for Linux. That would also be an interesting platform to smoke.