Add Travis-CI configuration

[paultcochrane]

Oddly enough, the test suite passes on my local system, but not on the Travis infrastructure, hence this PR is submitted partially as adding a feature to the repo and partially as an issue to show that there's a problem. The error produced on Travis is:

t/01-load.t .. ===SORRY!===
Type 'Test::Builder::Plan::Generic' is not declared
at /home/travis/build/paultcochrane/p6-test-builder/lib/Test/Builder.pm (Test::Builder):144
------>     has Test::Builder::Plan::Generic⏏ $!plan;
Malformed has
at /home/travis/build/paultcochrane/p6-test-builder/lib/Test/Builder.pm (Test::Builder):144
------>     has Test::Builder::Plan::⏏Generic $!plan;

which is, well, strange, since Test::Builder::Plan::Generic exists and should be available via the use statement to Test::Builder::Plan in the test file. Unfortunately, I've no idea what the underlying problem is, nor how to fix it :-/ Nevertheless, hopefully this gives someone else sufficient information to start debugging the issue and hopefully to resolve it.

[jonathanstowe]

That is odd, I'll take a look later.

[paultcochrane]

@jonathanstowe have you had a chance to look into this problem?

[ugexe]

I presume its not failing for you locally because you are not testing on the same version of perl6 that is getting used on TravisCI. I just tested locally on moar-2016.05 (pass) and a fresh moar-blead (fail)

[paultcochrane]

@ugexe you're right, it's only happening on blead atm. I was using 2016.10 from Debian Stretch (testing), hence wasn't seeing the issue locally. I've managed to reduce the issue to this:

$ cat lib/Test/Builder/Test.pm
class Test::Builder::Test { }

$ cat lib/Test/Builder/Plan.pm
role Test::Builder::Plan::Generic { }
class Test::Builder::Plan does Test::Builder::Plan::Generic { }

$ cat lib/Test/Builder.pm
use Test::Builder::Test;
use Test::Builder::Plan;

class Test::Builder {
    has Test::Builder::Plan::Generic $!plan;
}

If one then tries to use Test::Builder the error I mentioned in an earlier comment appears (i.e. Test::Builder::Plan::Generic isn't defined). E.g. one can try this via:

$ perl6 -Ilib -e 'use Test::Builder'

If one then comments out the use statement for Test::Builder::Test, the above command works and Test::Builder can be used without problem. Also, if one renames lib/Test/Builder/Test.pm to something else, e.g. lib/Test/Builder/Tester.pm and renames the class within to be Test::Builder::Tester, then the use Test::Builder also works without problem. I'm not sure what the actual problem here is; whether it's a problem with Rakudo, or whether this is something that Test::Builder is doing wrong. Any ideas would be very welcome!

[ugexe]

Seems like a rakudo bug. Renaming everything to Tester::Builder::Tester reintroduces the bug, so would seem to be somewhat related to identical name parts being present.

[jonathanstowe]

So, who wants to golf this to something reproducible for a rakudobug?

[paultcochrane]

A git bisect shows that the issue appears in Rakudo at this commit: ab946945735042ff99953f6636bdf98acd5bfc71. I'll see if I can golf the problem a bit more and submit a rakudobug.

[ugexe]

@paultcochrane here's a golf:
Works: perl6 -e 'class A::B::A { }; role A::B::C { }; class A::B { has A::B::C $!x; };'
Fails: perl6 -e '{ class A::B::A { }; }; role A::B::C { }; class A::B { has A::B::C $!x; };'
Works: perl6 -e '{ class A::B::X { }; }; role A::B::C { }; class A::B { has A::B::C $!x; };'

[paultcochrane]

BTW: here's the bug report in RT: https://rt.perl.org/Ticket/Display.html?id=130424

[lizmat]

Travis is no more, so closing