lib/bundler/resolver.rb
# frozen_string_literal: true
module Bundler
class Resolver
require_relative "vendored_molinillo"
require_relative "resolver/spec_group"
# Figures out the best possible configuration of gems that satisfies
# the list of passed dependencies and any child dependencies without
# causing any gem activation errors.
#
# ==== Parameters
# *dependencies<Gem::Dependency>:: The list of dependencies to resolve
#
# ==== Returns
# <GemBundle>,nil:: If the list of dependencies can be resolved, a
# collection of gemspecs is returned. Otherwise, nil is returned.
def self.resolve(requirements, index, source_requirements = {}, base = [], gem_version_promoter = GemVersionPromoter.new, additional_base_requirements = [], platforms = nil)
platforms = Set.new(platforms) if platforms
base = SpecSet.new(base) unless base.is_a?(SpecSet)
resolver = new(index, source_requirements, base, gem_version_promoter, additional_base_requirements, platforms)
result = resolver.start(requirements)
SpecSet.new(result)
end
def initialize(index, source_requirements, base, gem_version_promoter, additional_base_requirements, platforms)
@index = index
@source_requirements = source_requirements
@base = base
@resolver = Molinillo::Resolver.new(self, self)
@search_for = {}
@base_dg = Molinillo::DependencyGraph.new
@base.each do |ls|
dep = Dependency.new(ls.name, ls.version)
@base_dg.add_vertex(ls.name, DepProxy.new(dep, ls.platform), true)
end
additional_base_requirements.each {|d| @base_dg.add_vertex(d.name, d) }
@platforms = platforms
@gem_version_promoter = gem_version_promoter
@allow_bundler_dependency_conflicts = Bundler.feature_flag.allow_bundler_dependency_conflicts?
@use_gvp = Bundler.feature_flag.use_gem_version_promoter_for_major_updates? || !@gem_version_promoter.major?
@lockfile_uses_separate_rubygems_sources = Bundler.feature_flag.disable_multisource?
end
def start(requirements)
@gem_version_promoter.prerelease_specified = @prerelease_specified = {}
requirements.each {|dep| @prerelease_specified[dep.name] ||= dep.prerelease? }
verify_gemfile_dependencies_are_found!(requirements)
dg = @resolver.resolve(requirements, @base_dg)
dg.
tap {|resolved| validate_resolved_specs!(resolved) }.
map(&:payload).
reject {|sg| sg.name.end_with?("\0") }.
map(&:to_specs).
flatten
rescue Molinillo::VersionConflict => e
message = version_conflict_message(e)
raise VersionConflict.new(e.conflicts.keys.uniq, message)
rescue Molinillo::CircularDependencyError => e
names = e.dependencies.sort_by(&:name).map {|d| "gem '#{d.name}'" }
raise CyclicDependencyError, "Your bundle requires gems that depend" \
" on each other, creating an infinite loop. Please remove" \
" #{names.count > 1 ? "either " : ""}#{names.join(" or ")}" \
" and try again."
end
include Molinillo::UI
# Conveys debug information to the user.
#
# @param [Integer] depth the current depth of the resolution process.
# @return [void]
def debug(depth = 0)
return unless debug?
debug_info = yield
debug_info = debug_info.inspect unless debug_info.is_a?(String)
warn debug_info.split("\n").map {|s| "BUNDLER: " + " " * depth + s }
end
def debug?
return @debug_mode if defined?(@debug_mode)
@debug_mode =
ENV["BUNDLER_DEBUG_RESOLVER"] ||
ENV["BUNDLER_DEBUG_RESOLVER_TREE"] ||
ENV["DEBUG_RESOLVER"] ||
ENV["DEBUG_RESOLVER_TREE"] ||
false
end
def before_resolution
Bundler.ui.info "Resolving dependencies...", debug?
end
def after_resolution
Bundler.ui.info ""
end
def indicate_progress
Bundler.ui.info ".", false unless debug?
end
include Molinillo::SpecificationProvider
def dependencies_for(specification)
specification.dependencies_for_activated_platforms
end
def search_for(dependency)
platform = dependency.__platform
dependency = dependency.dep unless dependency.is_a? Gem::Dependency
search = @search_for[dependency] ||= begin
index = index_for(dependency)
results = index.search(dependency, @base[dependency.name])
if vertex = @base_dg.vertex_named(dependency.name)
locked_requirement = vertex.payload.requirement
end
if !@prerelease_specified[dependency.name] && (!@use_gvp || locked_requirement.nil?)
# Move prereleases to the beginning of the list, so they're considered
# last during resolution.
pre, results = results.partition {|spec| spec.version.prerelease? }
results = pre + results
end
spec_groups = if results.any?
nested = []
results.each do |spec|
version, specs = nested.last
if version == spec.version
specs << spec
else
nested << [spec.version, [spec]]
end
end
nested.reduce([]) do |groups, (version, specs)|
next groups if locked_requirement && !locked_requirement.satisfied_by?(version)
spec_group = SpecGroup.new(specs)
spec_group.ignores_bundler_dependencies = @allow_bundler_dependency_conflicts
groups << spec_group
end
else
[]
end
# GVP handles major itself, but it's still a bit risky to trust it with it
# until we get it settled with new behavior. For 2.x it can take over all cases.
if !@use_gvp
spec_groups
else
@gem_version_promoter.sort_versions(dependency, spec_groups)
end
end
selected_sgs = []
search.each do |sg|
next unless sg.for?(platform)
# Add a spec group for "non platform specific spec" as the fallback
# spec group.
sg_ruby = sg.copy_for(Gem::Platform::RUBY)
selected_sgs << sg_ruby if sg_ruby
sg_all_platforms = nil
all_platforms = @platforms + [platform]
sorted_all_platforms = self.class.sort_platforms(all_platforms)
sorted_all_platforms.reverse_each do |other_platform|
if sg_all_platforms.nil?
sg_all_platforms = sg.copy_for(other_platform)
else
sg_all_platforms.activate_platform!(other_platform)
end
end
selected_sgs << sg_all_platforms
end
selected_sgs
end
def index_for(dependency)
source = @source_requirements[dependency.name]
if source
source.specs
elsif @lockfile_uses_separate_rubygems_sources
Index.build do |idx|
if dependency.all_sources
dependency.all_sources.each {|s| idx.add_source(s.specs) if s }
else
idx.add_source @source_requirements[:default].specs
end
end
else
@index
end
end
def name_for(dependency)
dependency.name
end
def name_for_explicit_dependency_source
Bundler.default_gemfile.basename.to_s
rescue StandardError
"Gemfile"
end
def name_for_locking_dependency_source
Bundler.default_lockfile.basename.to_s
rescue StandardError
"Gemfile.lock"
end
def requirement_satisfied_by?(requirement, activated, spec)
requirement.matches_spec?(spec) || spec.source.is_a?(Source::Gemspec)
end
def relevant_sources_for_vertex(vertex)
if vertex.root?
[@source_requirements[vertex.name]]
elsif @lockfile_uses_separate_rubygems_sources
vertex.recursive_predecessors.map do |v|
@source_requirements[v.name]
end << @source_requirements[:default]
end
end
def sort_dependencies(dependencies, activated, conflicts)
dependencies.sort_by do |dependency|
dependency.all_sources = relevant_sources_for_vertex(activated.vertex_named(dependency.name))
name = name_for(dependency)
vertex = activated.vertex_named(name)
[
@base_dg.vertex_named(name) ? 0 : 1,
vertex.payload ? 0 : 1,
vertex.root? ? 0 : 1,
amount_constrained(dependency),
conflicts[name] ? 0 : 1,
vertex.payload ? 0 : search_for(dependency).count,
self.class.platform_sort_key(dependency.__platform),
]
end
end
# Sort platforms from most general to most specific
def self.sort_platforms(platforms)
platforms.sort_by do |platform|
platform_sort_key(platform)
end
end
def self.platform_sort_key(platform)
# Prefer specific platform to not specific platform
return ["99-LAST", "", "", ""] if Gem::Platform::RUBY == platform
["00", *platform.to_a.map {|part| part || "" }]
end
private
# 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
def amount_constrained(dependency)
@amount_constrained ||= {}
@amount_constrained[dependency.name] ||= begin
if (base = @base[dependency.name]) && !base.empty?
dependency.requirement.satisfied_by?(base.first.version) ? 0 : 1
else
all = index_for(dependency).search(dependency.name).size
if all <= 1
all - 1_000_000
else
search = search_for(dependency)
search = @prerelease_specified[dependency.name] ? search.count : search.count {|s| !s.version.prerelease? }
search - all
end
end
end
end
def verify_gemfile_dependencies_are_found!(requirements)
requirements.each do |requirement|
name = requirement.name
next if name == "bundler"
next unless search_for(requirement).empty?
cache_message = begin
" or in gems cached in #{Bundler.settings.app_cache_path}" if Bundler.app_cache.exist?
rescue GemfileNotFound
nil
end
if (base = @base[name]) && !base.empty?
version = base.first.version
message = "You have requested:\n" \
" #{name} #{requirement.requirement}\n\n" \
"The bundle currently has #{name} locked at #{version}.\n" \
"Try running `bundle update #{name}`\n\n" \
"If you are updating multiple gems in your Gemfile at once,\n" \
"try passing them all to `bundle update`"
elsif source = @source_requirements[name]
specs = source.specs[name]
versions_with_platforms = specs.map {|s| [s.version, s.platform] }
message = String.new("Could not find gem '#{SharedHelpers.pretty_dependency(requirement)}' in #{source}#{cache_message}.\n")
message << if versions_with_platforms.any?
"The source contains '#{name}' at: #{formatted_versions_with_platforms(versions_with_platforms)}"
else
"The source does not contain any versions of '#{name}'"
end
else
message = "Could not find gem '#{requirement}' in any of the gem sources " \
"listed in your Gemfile#{cache_message}."
end
raise GemNotFound, message
end
end
def formatted_versions_with_platforms(versions_with_platforms)
version_platform_strs = versions_with_platforms.map do |vwp|
version = vwp.first
platform = vwp.last
version_platform_str = String.new(version.to_s)
version_platform_str << " #{platform}" unless platform.nil? || platform == Gem::Platform::RUBY
version_platform_str
end
version_platform_strs.join(", ")
end
def version_conflict_message(e)
# only show essential conflicts, if possible
conflicts = e.conflicts.dup
conflicts.delete_if do |_name, conflict|
deps = conflict.requirement_trees.map(&:last).flatten(1)
!Bundler::VersionRanges.empty?(*Bundler::VersionRanges.for_many(deps.map(&:requirement)))
end
e = Molinillo::VersionConflict.new(conflicts, e.specification_provider) unless conflicts.empty?
solver_name = "Bundler"
possibility_type = "gem"
e.message_with_trees(
:solver_name => solver_name,
:possibility_type => possibility_type,
:reduce_trees => lambda do |trees|
# called first, because we want to reduce the amount of work required to find maximal empty sets
trees = trees.uniq {|t| t.flatten.map {|dep| [dep.name, dep.requirement] } }
# bail out if tree size is too big for Array#combination to make any sense
return trees if trees.size > 15
maximal = 1.upto(trees.size).map do |size|
trees.map(&:last).flatten(1).combination(size).to_a
end.flatten(1).select do |deps|
Bundler::VersionRanges.empty?(*Bundler::VersionRanges.for_many(deps.map(&:requirement)))
end.min_by(&:size)
trees.reject! {|t| !maximal.include?(t.last) } if maximal
trees.sort_by {|t| t.reverse.map(&:name) }
end,
:printable_requirement => lambda {|req| SharedHelpers.pretty_dependency(req) },
:additional_message_for_conflict => lambda do |o, name, conflict|
if name == "bundler"
o << %(\n Current Bundler version:\n bundler (#{Bundler::VERSION}))
other_bundler_required = !conflict.requirement.requirement.satisfied_by?(Gem::Version.new(Bundler::VERSION))
end
if name == "bundler" && other_bundler_required
o << "\n"
o << "This Gemfile requires a different version of Bundler.\n"
o << "Perhaps you need to update Bundler by running `gem install bundler`?\n"
end
if conflict.locked_requirement
o << "\n"
o << %(Running `bundle update` will rebuild your snapshot from scratch, using only\n)
o << %(the gems in your Gemfile, which may resolve the conflict.\n)
elsif !conflict.existing
o << "\n"
relevant_sources = if conflict.requirement.source
[conflict.requirement.source]
elsif conflict.requirement.all_sources
conflict.requirement.all_sources
elsif @lockfile_uses_separate_rubygems_sources
# every conflict should have an explicit group of sources when we
# enforce strict pinning
raise "no source set for #{conflict}"
else
[]
end.compact.map(&:to_s).uniq.sort
metadata_requirement = name.end_with?("\0")
o << "Could not find gem '" unless metadata_requirement
o << SharedHelpers.pretty_dependency(conflict.requirement)
o << "'" unless metadata_requirement
if conflict.requirement_trees.first.size > 1
o << ", which is required by "
o << "gem '#{SharedHelpers.pretty_dependency(conflict.requirement_trees.first[-2])}',"
end
o << " "
o << if relevant_sources.empty?
"in any of the sources.\n"
elsif metadata_requirement
"is not available in #{relevant_sources.join(" or ")}"
else
"in any of the relevant sources:\n #{relevant_sources * "\n "}\n"
end
end
end,
:version_for_spec => lambda {|spec| spec.version },
:incompatible_version_message_for_conflict => lambda do |name, _conflict|
if name.end_with?("\0")
%(#{solver_name} found conflicting requirements for the #{name} version:)
else
%(#{solver_name} could not find compatible versions for #{possibility_type} "#{name}":)
end
end
)
end
def validate_resolved_specs!(resolved_specs)
resolved_specs.each do |v|
name = v.name
next unless sources = relevant_sources_for_vertex(v)
sources.compact!
if default_index = sources.index(@source_requirements[:default])
sources.delete_at(default_index)
end
sources.reject! {|s| s.specs[name].empty? }
sources.uniq!
next if sources.size <= 1
multisource_disabled = Bundler.feature_flag.disable_multisource?
msg = ["The gem '#{name}' was found in multiple relevant sources."]
msg.concat sources.map {|s| " * #{s}" }.sort
msg << "You #{multisource_disabled ? :must : :should} add this gem to the source block for the source you wish it to be installed from."
msg = msg.join("\n")
raise SecurityError, msg if multisource_disabled
Bundler.ui.warn "Warning: #{msg}"
end
end
end
end