Replace the rubygems-specific lockfile parser with Bundler's parser

Manifest.txt

@@ -462,8 +462,6 @@ lib/rubygems/request/https_pool.rb
 lib/rubygems/request_set.rb
 lib/rubygems/request_set/gem_dependency_api.rb
 lib/rubygems/request_set/lockfile.rb
-lib/rubygems/request_set/lockfile/parser.rb
-lib/rubygems/request_set/lockfile/tokenizer.rb
 lib/rubygems/requirement.rb
 lib/rubygems/resolver.rb
 lib/rubygems/resolver/activation_request.rb

Rakefile

@@ -74,6 +74,7 @@ Rake::TestTask.new do |t|
     t.ruby_opts.unshift("--disable-gems", "-r#{coverage_setup}")
   end
 
+  t.libs << "bundler/lib"
   t.libs << "test"
   t.test_files = FileList["test/**/test_*.rb"]
 end

bundler/lib/bundler/lockfile_parser.rb

@@ -95,14 +95,14 @@ def self.bundled_with
       lockfile_contents.split(BUNDLED).last.strip
     end
 
-    def initialize(lockfile, strict: false)
+    def initialize(lockfile, strict: false, lockfile_path: nil)
       @platforms    = []
       @sources      = []
       @metadata_source = Source::Metadata.new
       @dependencies = {}
       @parse_method = nil
       @specs        = {}
-      @lockfile_path = begin
+      @lockfile_path = lockfile_path || begin
         SharedHelpers.relative_lockfile_path
       rescue GemfileNotFound
         "Gemfile.lock"

lib/rubygems/request_set.rb

@@ -322,11 +322,8 @@ def load_gemdeps(path, without_groups = [], installing = false)
     @git_set.root_dir = @install_dir
 
     lock_file = "#{File.expand_path(path)}.lock"
-    begin
-      tokenizer = Gem::RequestSet::Lockfile::Tokenizer.from_file lock_file
-      parser = tokenizer.make_parser self, []
-      parser.parse
-    rescue Errno::ENOENT
+    if File.exist?(lock_file)
+      load_lockfile lock_file
     end
 
     gf = Gem::RequestSet::GemDependencyAPI.new self, path
@@ -335,6 +332,63 @@ def load_gemdeps(path, without_groups = [], installing = false)
     gf.load
   end
 
+  def load_lockfile(lock_file) # :nodoc:
+    require "bundler"
+    require "bundler/lockfile_parser"
+
+    # Bundler::Source::Path resolves relative `remote:` paths against
+    # Bundler.root, which raises when there is no Gemfile in the working
+    # directory. Anchor it to the lockfile's directory so PATH sections in a
+    # `gem install -g` lockfile can be parsed without a Bundler environment.
+    previous_root = Bundler.instance_variable_get(:@root)
+    Bundler.instance_variable_set(:@root, Pathname.new(File.expand_path(File.dirname(lock_file))))
+
+    parser = Bundler::LockfileParser.new(File.read(lock_file), lockfile_path: lock_file)
+
+    parser.specs.group_by(&:source).each do |source, specs|
+      case source
+      when Bundler::Source::Rubygems
+        remotes = source.remotes.map {|remote| Gem::Source.new(remote.to_s) }
+        remotes << Gem::Source.new(Gem::DEFAULT_HOST) if remotes.empty?
+        lock_set = Gem::Resolver::LockSet.new(remotes)
+        specs.each do |spec|
+          added = lock_set.add(spec.name, spec.version.to_s, spec.platform)
+          spec.dependencies.each do |dep|
+            added.each {|s| s.add_dependency dep }
+          end
+        end
+        @sets << lock_set
+      when Bundler::Source::Git
+        git_set = Gem::Resolver::GitSet.new
+        git_set.root_dir = @install_dir
+        specs.each do |spec|
+          git_spec = git_set.add_git_spec(
+            spec.name,
+            spec.version.to_s,
+            source.uri.to_s,
+            source.revision,
+            source.submodules || false
+          )
+          spec.dependencies.each {|dep| git_spec.add_dependency dep }
+        end
+        @sets << git_set
+      when Bundler::Source::Path
+        vendor_set = Gem::Resolver::VendorSet.new
+        specs.each do |spec|
+          loaded = vendor_set.add_vendor_gem(spec.name, source.path.to_s)
+          spec.dependencies.each {|dep| loaded.dependencies << dep }
+        end
+        @sets << vendor_set
+      end
+    end
+
+    parser.dependencies.each_value do |dep|
+      gem dep.name, *dep.requirement.as_list
+    end
+  ensure
+    Bundler.instance_variable_set(:@root, previous_root) if defined?(previous_root)
+  end
+
   def pretty_print(q) # :nodoc:
     q.group 2, "[RequestSet:", "]" do
       q.breakable
@@ -462,4 +516,3 @@ def tsort_each_child(node) # :nodoc:
 
 require_relative "request_set/gem_dependency_api"
 require_relative "request_set/lockfile"
-require_relative "request_set/lockfile/tokenizer"

lib/rubygems/request_set/lockfile.rb

@@ -231,5 +231,3 @@ def requests
     @set.sorted_requests
   end
 end
-
-require_relative "lockfile/tokenizer"