module Gems::Ordering

Orders the resources that carry the number of a gem version, included in {Gem} and {Version}

A resource is ordered by the name of its gem, then by its number as RubyGems orders numbers, and then by its platform and the Ruby ABI it was built for, so that the gems and versions of a response sort as ‘gem list` orders them rather than as the strings they are written with, where “7.0.10” comes before “7.0.9”. Each class reads the number from the key its endpoints answer with: {Gem#gem_version} from `version`, and {Version#gem_version} from `number`.

‘Comparable` is deliberately not included: a resource is equal to another by its identity, whatever fields the endpoint it came from answered with (see {Resource#==}), where `Comparable` would answer that it is equal to whatever it is ordered alongside, such as the same number of another gem.

@api public

Public Instance Methods

<=> (other)

Compare with another resource of the same kind

@api public @param other [Object] the object to compare with @return [Integer, nil] -1, 0, or 1, or nil when the other object is not the same kind of resource, or either

resource carries no number, or one RubyGems cannot read

@example Read the latest version of a gem

Gems.versions("rails").max.number

@example Order the versions of a gem, oldest first

Gems.versions("rails").sort

@example Order the gems a search answered with

Gems.search("cucumber").sort

# File lib/gems/ordering.rb, line 31
def <=>(other)
  return unless other.instance_of?(self.class)

  ordering&.<=>(other.ordering) # steep:ignore NoMethod
end

Protected Instance Methods

ordering ()

The values the resource is ordered by

A resource answers with these to the resource it is ordered against, rather than to a caller, as it answers with its identity to the resource it is compared with (see {Resource#identity}). There are none for a resource that carries no number, or one RubyGems cannot read, so that ordering it against another answers with nil rather than with an order the numbers do not give.

@api private @return [Array<Object>, nil] the name, number, platform, and Ruby ABI, or nil when there is no number to order

by

# File lib/gems/ordering.rb, line 49
def ordering
  version = gem_version
  [name.to_s, version, platform.to_s, ruby_abi.to_s] if version
end