Parsing makes cuckooed packages inherit first packages version

[kentfredric]

As discovered by @neilbowers, this file: https://metacpan.org/source/NEILB/Text-Autoformat-1.69/lib/Text/Autoformat.pm

Entered the index such that the single file mapped to:

{ "Text::Autoformat" : 0.69,
  "Text::Autoformat::Hang" : 0.69,
  "Text::Autoformat::NullHang": 0.69 }

Whereas expected indexing was:

{ "Text::Autoformat" : 0.69,
  "Text::Autoformat::Hang" : null,
  "Text::Autoformat::NullHang": null }

He recently shipped his distribution with Module::Build, which automatically did meta.provides for him:

https://metacpan.org/diff/file?target=NEILB/Text-Autoformat-1.70/&source=NEILB/Text-Autoformat-1.69/

It mimicked the expected pattern above

{ "Text::Autoformat" : 0.70,
  "Text::Autoformat::Hang" : null,
  "Text::Autoformat::NullHang": null }

And caused a "Backwards versioning" issue.

It is believed that the original behaviour of indexing the latter packages under the same version as the former is an error.

[karenetheridge]

This feels like a recent regression to me -- surely if this behaviour had always been there we would have noticed it sooner.

[rjbs]

Maybe, but I'm not sure what change might have introduced this kind of thing recently. Anyway, easy to test and probably easy to fix! :)

[charsbar]

No. It's been there for quite a long time, at least since 2003 (I stopped tracking when I found the following example, but it should be older).

https://github.com/andk/pause/blob/2633f058b2f312d7336ae3948e088eb3edfc9112/cron/mldistwatch#L1403

If we do need to make PAUSE work like Module::Build, just replacing $version in the following line with "undef" (and reindex every non-simile packages) should do the trick, but I'm not so sure which should be fixed actually.

https://github.com/andk/pause/blob/master/lib/PAUSE/pmfile.pm#L312