class Gem::Resolver

Given a set of Gem::Dependency objects as needed and a way to query the set of available specs via set, calculates a set of ActivationRequest objects which indicate all the specs that should be activated to meet the all the requirements.

Constants

DEBUG_RESOLVER: If the DEBUG_RESOLVER environment variable is set then debugging mode is enabled for the resolver. This will display information about the state of the resolver while a set of dependencies is being resolved.

Attributes

conflicts[R]

Contains all the conflicts encountered while doing resolution

development[RW]

Set to true if development dependencies should be considered.

ignore_dependencies[RW]

When true, no dependencies are looked up for requested gems.

missing[R]

List of dependencies that could not be found in the configured sources.

soft_missing[RW]

When a missing dependency, don't stop. Just go on and record what was missing.

stats[R]

Public Class Methods

compose_sets(*sets) click to toggle source

Combines sets into a ComposedSet that allows specification lookup in a uniform manner. If one of the sets is itself a ComposedSet its sets are flattened into the result ComposedSet.

# File lib/rubygems/resolver.rb, line 57
def self.compose_sets *sets
  sets.compact!

  sets = sets.map do |set|
    case set
    when Gem::Resolver::BestSet then
      set
    when Gem::Resolver::ComposedSet then
      set.sets
    else
      set
    end
  end.flatten

  case sets.length
  when 0 then
    raise ArgumentError, 'one set in the composition must be non-nil'
  when 1 then
    sets.first
  else
    Gem::Resolver::ComposedSet.new(*sets)
  end
end

for_current_gems(needed) click to toggle source

Creates a Resolver that queries only against the already installed gems for the needed dependencies.

# File lib/rubygems/resolver.rb, line 85
def self.for_current_gems needed
  new needed, Gem::Resolver::CurrentSet.new
end

new(needed, set = nil) click to toggle source

Create Resolver object which will resolve the tree starting with needed Dependency objects.

set is an object that provides where to look for specifications to satisfy the Dependencies. This defaults to IndexSet, which will query rubygems.org.

# File lib/rubygems/resolver.rb, line 97
def initialize needed, set = nil
  @set = set || Gem::Resolver::IndexSet.new
  @needed = needed

  @conflicts           = []
  @development         = false
  @ignore_dependencies = false
  @missing             = []
  @soft_missing        = false
  @stats               = Gem::Resolver::Stats.new
end

Public Instance Methods

resolve() click to toggle source

Proceed with resolution! Returns an array of ActivationRequest objects.

# File lib/rubygems/resolver.rb, line 161
def resolve
  @conflicts = []

  needed = Gem::Resolver::RequirementList.new

  @needed.reverse_each do |n|
    request = Gem::Resolver::DependencyRequest.new n, nil

    needed.add request
    @stats.requirement!
  end

  @stats.record_requirements needed

  res = resolve_for needed, nil

  raise Gem::DependencyResolutionError, res if
    res.kind_of? Gem::Resolver::Conflict

  res.to_a
end