Possible "Use of uninitialized value in open" warning in _taintedness

[eserte]

The LWP::ConsoleLogger test suite fails on some of my smoker systems, caused by a warning originating in WWW::Mechanize:

Use of uninitialized value in open at /opt/perl-5.41.5/lib/site_perl/5.41.5/WWW/Mechanize.pm line 1650.

It seems that this warning happens because at least one value in %INC is undef, which results in an open call on an undefined filename.

The undefined value belongs to the Mojo/Reactor/EV.pm key and it can also be reproduced by this oneliner:

$ perl5.41.5 -MMojo::Reactor -MData::Dumper -e 'Mojo::Reactor::detect(); $Data::Dumper::Sortkeys=1; warn Dumper(\%INC)'
...
          'Mojo/Reactor.pm' => '/opt/perl-5.41.5/lib/site_perl/5.41.5/Mojo/Reactor.pm',
          'Mojo/Reactor/EV.pm' => undef,
          'Mojo/Reactor/Poll.pm' => '/opt/perl-5.41.5/lib/site_perl/5.41.5/Mojo/Reactor/Poll.pm',
...

In any case, probably within the for loop something like next if !defined $filename should be done.

[oalders]

Thanks @eserte! Do you happen to have an incantation to reproduce the error via Docker?

[petdance]

Didn't we get rid of all the taint stuff?

[oalders]

Didn't we get rid of all the taint stuff?

Apparently not. I guess now would be a good time?

[petdance]

I must be losing my mind. What DID we remove taintedness from then?

[petdance]

No matter, I'll pull a branch to remove it.

[eserte]

If you still need a Dockerfile for reproducing it:

# docker build -t perl-test . && docker run perl-test
# https://github.com/libwww-perl/WWW-Mechanize/issues/382
FROM perl:5.41.5-bookworm

# install Mojo::Reactor + Mojo::Reactor::EV (but without EV!)
RUN cpan Mojo

# need to switch to non-root because of https://rt.cpan.org/Ticket/Display.html?id=156367
RUN adduser somebody --shell /bin/bash
USER somebody
ENV SHELL /bin/bash

CMD cpan -t LWP::ConsoleLogger

Runs for almost half an hour due to many deps. Best to redirect output to a file, to find the warnings afterwards.

[petdance]

See PR #383

[oalders]

Thanks, @eserte!