Plain perl mistaken for Perl6

[kentfredric]

I was forwarded here by github relating to a failure to highlight this document: https://gist.github.com/kentfredric/04b64a80c5d90eea2924

Repeated attempt to indicate what language it was using the file extension always resulted in it thinking I was using Perl6.

Looking into your heuristics ( as per #2042 ) I find this: https://github.com/github/linguist/blob/master/lib/linguist/heuristics.rb#L54-L57

disambiguate "Perl", "Perl6", "Prolog" do |data|
  if data.include?("use v6")
    Language["Perl6"]
  elsif data.include?("use strict")
    Language["Perl"]
  elsif data.include?(":-")
    Language["Prolog"]
  end
end

That perl heuristic is incredibly narrow and will exclude anything that is relying on strict to be injected by another pragma/module.

use Moose and use Moo both inject strict.
use 5.xxx injects strict where "xxx" can be converted to an integer that is 12 or greater.

Though it seems to me, a good heuristic to use in addition to use strict would be :

use\s+v?5\.

Which should catch any perl5 document that is using an explicit perl version requirement.

As would:

^#![^ ]*perl($|[^6])

( Because "perl" may never assume to mean "perl6", and may only imply perl5 )

[bkeepers]

Thanks for reporting the issue!

Though it seems to me, a good heuristic to use in addition to use strict would be…

Cool, I added that in #2092

^#![^ ]*perl($|[^6])

The shebang strategy, which runs before the heuristics, should properly detect the perl version.

[arfon]

This was fixed in #2092