1 files changed, 187 insertions, 0 deletions
diff --git a/lib/bundler/spec_set.rb b/lib/bundler/spec_set.rb
new file mode 100644
index 0000000000..9642633578
--- /dev/null
+++ b/lib/bundler/spec_set.rb
@@ -0,0 +1,187 @@
+# frozen_string_literal: true
+require "tsort"
+require "forwardable"
+require "set"
+
+module Bundler
+  class SpecSet
+    extend Forwardable
+    include TSort, Enumerable
+
+    def_delegators :@specs, :<<, :length, :add, :remove, :size, :empty?
+    def_delegators :sorted, :each
+
+    def initialize(specs)
+      @specs = specs
+    end
+
+    def for(dependencies, skip = [], check = false, match_current_platform = false, raise_on_missing = true)
+      handled = Set.new
+      deps = dependencies.dup
+      specs = []
+      skip += ["bundler"]
+
+      loop do
+        break unless dep = deps.shift
+        next if !handled.add?(dep) || skip.include?(dep.name)
+
+        if spec = spec_for_dependency(dep, match_current_platform)
+          specs << spec
+
+          spec.dependencies.each do |d|
+            next if d.type == :development
+            d = DepProxy.new(d, dep.__platform) unless match_current_platform
+            deps << d
+          end
+        elsif check
+          return false
+        elsif raise_on_missing
+          raise "Unable to find a spec satisfying #{dep} in the set. Perhaps the lockfile is corrupted?"
+        end
+      end
+
+      if spec = lookup["bundler"].first
+        specs << spec
+      end
+
+      check ? true : SpecSet.new(specs)
+    end
+
+    def valid_for?(deps)
+      self.for(deps, [], true)
+    end
+
+    def [](key)
+      key = key.name if key.respond_to?(:name)
+      lookup[key].reverse
+    end
+
+    def []=(key, value)
+      @specs << value
+      @lookup = nil
+      @sorted = nil
+      value
+    end
+
+    def sort!
+      self
+    end
+
+    def to_a
+      sorted.dup
+    end
+
+    def to_hash
+      lookup.dup
+    end
+
+    def materialize(deps, missing_specs = nil)
+      materialized = self.for(deps, [], false, true, missing_specs).to_a
+      deps = materialized.map(&:name).uniq
+      materialized.map! do |s|
+        next s unless s.is_a?(LazySpecification)
+        s.source.dependency_names = deps if s.source.respond_to?(:dependency_names=)
+        spec = s.__materialize__
+        unless spec
+          unless missing_specs
+            raise GemNotFound, "Could not find #{s.full_name} in any of the sources"
+          end
+          missing_specs << s
+        end
+        spec
+      end
+      SpecSet.new(missing_specs ? materialized.compact : materialized)
+    end
+
+    # Materialize for all the specs in the spec set, regardless of what platform they're for
+    # This is in contrast to how for does platform filtering (and specifically different from how `materialize` calls `for` only for the current platform)
+    # @return [Array<Gem::Specification>]
+    def materialized_for_all_platforms
+      names = @specs.map(&:name).uniq
+      @specs.map do |s|
+        next s unless s.is_a?(LazySpecification)
+        s.source.dependency_names = names if s.source.respond_to?(:dependency_names=)
+        spec = s.__materialize__
+        raise GemNotFound, "Could not find #{s.full_name} in any of the sources" unless spec
+        spec
+      end
+    end
+
+    def merge(set)
+      arr = sorted.dup
+      set.each do |s|
+        next if arr.any? {|s2| s2.name == s.name && s2.version == s.version && s2.platform == s.platform }
+        arr << s
+      end
+      SpecSet.new(arr)
+    end
+
+    def find_by_name_and_platform(name, platform)
+      @specs.detect {|spec| spec.name == name && spec.match_platform(platform) }
+    end
+
+    def what_required(spec)
+      unless req = find {|s| s.dependencies.any? {|d| d.type == :runtime && d.name == spec.name } }
+        return [spec]
+      end
+      what_required(req) << spec
+    end
+
+  private
+
+    def sorted
+      rake = @specs.find {|s| s.name == "rake" }
+      begin
+        @sorted ||= ([rake] + tsort).compact.uniq
+      rescue TSort::Cyclic => error
+        cgems = extract_circular_gems(error)
+        raise CyclicDependencyError, "Your bundle requires gems that depend" \
+          " on each other, creating an infinite loop. Please remove either" \
+          " gem '#{cgems[1]}' or gem '#{cgems[0]}' and try again."
+      end
+    end
+
+    def extract_circular_gems(error)
+      if Bundler.current_ruby.mri? && Bundler.current_ruby.on_19?
+        error.message.scan(/(\w+) \([^)]/).flatten
+      else
+        error.message.scan(/@name="(.*?)"/).flatten
+      end
+    end
+
+    def lookup
+      @lookup ||= begin
+        lookup = Hash.new {|h, k| h[k] = [] }
+        Index.sort_specs(@specs).reverse_each do |s|
+          lookup[s.name] << s
+        end
+        lookup
+      end
+    end
+
+    def tsort_each_node
+      # MUST sort by name for backwards compatibility
+      @specs.sort_by(&:name).each {|s| yield s }
+    end
+
+    def spec_for_dependency(dep, match_current_platform)
+      specs_for_platforms = lookup[dep.name]
+      if match_current_platform
+        Bundler.rubygems.platforms.reverse_each do |pl|
+          match = GemHelpers.select_best_platform_match(specs_for_platforms, pl)
+          return match if match
+        end
+        nil
+      else
+        GemHelpers.select_best_platform_match(specs_for_platforms, dep.__platform)
+      end
+    end
+
+    def tsort_each_child(s)
+      s.dependencies.sort_by(&:name).each do |d|
+        next if d.type == :development
+        lookup[d.name].each {|s2| yield s2 }
+      end
+    end
+  end
+end