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.
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.
TODO: Remove in RubyGems 3
Set to true if all development dependencies should be considered.
Set to true if immediate development dependencies should be considered.
When true, no dependencies are looked up for requested gems.
List of dependencies that could not be found in the configured sources.
Hash of gems to skip resolution. Keyed by gem name, with arrays of gem specifications as values.
When a missing dependency, don’t stop. Just go on and record what was missing.
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 62
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
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 tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 90
def self.for_current_gems needed
new needed, Gem::Resolver::CurrentSet.new
end
Creates a Resolver that queries only against the already installed gems for the needed dependencies.
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 102
def initialize needed, set = nil
@set = set || Gem::Resolver::IndexSet.new
@needed = needed
@development = false
@development_shallow = false
@ignore_dependencies = false
@missing = []
@skip_gems = {}
@soft_missing = false
@stats = Gem::Resolver::Stats.new
end
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 271
def allow_missing?(dependency)
@missing << dependency
@soft_missing
end
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 298
def amount_constrained(dependency)
@amount_constrained ||= {}
@amount_constrained[dependency.name] ||= begin
name_dependency = Gem::Dependency.new(dependency.name)
dependency_request_for_name = Gem::Resolver::DependencyRequest.new(name_dependency, dependency.requester)
all = @set.find_all(dependency_request_for_name).size
if all <= 1
all - SINGLE_POSSIBILITY_CONSTRAINT_PENALTY
else
search = search_for(dependency).size
search - all
end
end
end
returns an integer in (-infty, 0] a number closer to 0 means the dependency is less constraining
dependencies w/ 0 or 1 possibilities (ignoring version requirements) are given very negative values, so they always sort first, before dependencies that are unconstrained
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 177
def debug?
DEBUG_RESOLVER
end
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 257
def dependencies_for(specification)
return [] if @ignore_dependencies
spec = specification.spec
requests(spec, specification)
end
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 267
def name_for(dependency)
dependency.name
end
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 173
def output
@output ||= debug? ? $stdout : File.open(Gem::Util::NULL_DEVICE, 'w')
end
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 263
def requirement_satisfied_by?(requirement, activated, spec)
requirement.matches_spec? spec
end
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 186
def resolve
locking_dg = Molinillo::DependencyGraph.new
Molinillo::Resolver.new(self, self).resolve(@needed.map { |d| DependencyRequest.new d, nil }, locking_dg).tsort.map(&:payload).compact
rescue Molinillo::VersionConflict => e
conflict = e.conflicts.values.first
raise Gem::DependencyResolutionError, Conflict.new(conflict.requirement_trees.first.first, conflict.existing, conflict.requirement)
ensure
@output.close if defined?(@output) and !debug?
end
Proceed with resolution! Returns an array of ActivationRequest objects.
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 225
def search_for(dependency)
possibles, all = find_possible(dependency)
if !@soft_missing && possibles.empty?
@missing << dependency
exc = Gem::UnsatisfiableDependencyError.new dependency, all
exc.errors = @set.errors
raise exc
end
sources = []
groups = Hash.new { |hash, key| hash[key] = [] }
# create groups & sources in the same loop
sources = possibles.map { |spec|
source = spec.source
groups[source] << spec
source
}.uniq.reverse
activation_requests = []
sources.each do |source|
groups[source].
sort_by { |spec| [spec.version, Gem::Platform.local =~ spec.platform ? 1 : 0] }.
map { |spec| ActivationRequest.new spec, dependency, [] }.
each { |activation_request| activation_requests << activation_request }
end
activation_requests
end
# File tmp/rubies/ruby-2.5.9/lib/rubygems/resolver.rb, line 276
def sort_dependencies(dependencies, activated, conflicts)
dependencies.sort_by.with_index do |dependency, i|
name = name_for(dependency)
[
activated.vertex_named(name).payload ? 0 : 1,
amount_constrained(dependency),
conflicts[name] ? 0 : 1,
activated.vertex_named(name).payload ? 0 : search_for(dependency).count,
i # for stable sort
]
end
end