Improved handling of Semver pre-release versions

[benasher44]

Fixes CocoaPods/CocoaPods#5718

• Handle special case of missing first segment of pre-release segments (doesn't mean it wasn't handled before, just calling out this part in the diff)
• Updated according to Semver's predence spec (item 11 if it doesn't link you straight there):

Numeric identifiers always have lower precedence than non-numeric identifiers.

[segiddins]

amazing ❤️

with a CHANGELOG

[benasher44]

@segiddins what's the difference between Pod::Version and Pod::Vendor::Version? Should I add test cases for that one as well?

[segiddins]

@benasher44 Pod::Version is a subclass of the vendored RubyGems implementation, so that's not necessary :)

[benasher44]

👍

[benasher44]

@segiddins wait no I'm still confused. Pod::Version inherits from Pod::Vendor::Gem::Version, and Pod::Vendor::Gem::Version also implmements <=>. Pod::Vendor::Gem::Version's implementation of <=> looks how Pod::Version's used to look, so it should be prone to the same bug no?

[segiddins]

but Pod::Vendor::Gem::Version is never used directly, only via Pod::Version

[benasher44]

Huh so it's not. Looks like we only ever refer to Gem::Version (Pod::Version aside). Any reason not to collapse Pod::Vendor::Gem::Version into Pod::Version?

[segiddins]

To make it easier to merge in changes from upstream

[benasher44]

OH! This is just a clone of Gem::Version. Welp. This all makes sense now. Thanks!

[segiddins]

🚢