Fix #2813: Ignore self dependency

lib/bundler/installer.rb

@@ -284,33 +284,45 @@ def install_in_parallel(size, standalone)
        message = install_gem_from_spec spec, standalone, worker
        { :name => spec.name, :post_install => message }
      }
      specs.each do |spec|
        deps = spec.dependencies.select { |dep| dep.type != :development }
        if deps.empty?
          worker_pool.enq spec.name
          enqueued[spec.name] = true

      # Keys in the remains hash represent uninstalled gems specs.
      # We enqueue all gem specs that do not have any dependencies.
      # Later we call this lambda again to install specs that depended on
      # previously installed specifications. We continue until all specs
      # are installed.
      enqueue_remaining_specs = lambda do
        remains.keys.each do |name|
          next if enqueued[name]
          spec = name2spec[name]
          if ready_to_install?(spec, remains)
            worker_pool.enq name
            enqueued[name] = true
          end
        end
      end
      enqueue_remaining_specs.call

      until remains.empty?
        message = worker_pool.deq
        remains.delete message[:name]
        if message[:post_install]
          Installer.post_install_messages[message[:name]] = message[:post_install]
        end
        remains.keys.each do |name|
          next if enqueued[name]
          spec = name2spec[name]
          deps = spec.dependencies.select { |dep| remains[dep.name] and dep.type != :development }
          if deps.empty?
            worker_pool.enq name
            enqueued[name] = true
          end
        end
        enqueue_remaining_specs.call
      end
      message
    ensure
      worker_pool && worker_pool.stop
    end

    # We only want to install a gem spec if all its dependencies are met.
    # If the dependency is no longer in the `remains` hash then it has been met.
    # If a dependency is only development or is self referential it can be ignored.
    def ready_to_install?(spec, remains)
      spec.dependencies.none? do |dep|
        next if dep.type == :development || dep.name == spec.name
        remains[dep.name]
      end
    end
  end
end

spec/realworld/parallel_install_spec.rb

@@ -12,12 +12,25 @@
    (0..1).each {|i| expect(out).to include("#{i}: ") }

    bundle "show activesupport"
    expect(out).to match(/activesupport/)
    expect(out).to match(%r{gems/activesupport})

    bundle "show faker"
    expect(out).to match(/faker/)

    bundle "config jobs"
    expect(out).to match(/: "2"/)
  end

  it "installs even with circular dependency", :realworld => true do
    gemfile <<-G
      source 'https://rubygems.org'
      gem 'mongoid_auto_increment', "0.1.1"
    G

    bundle :install, :jobs => 2, :env => {"DEBUG" => "1"}
    (0..1).each {|i| expect(out).to include("#{i}: ") }

    bundle "show mongoid_auto_increment"
    expect(out).to match(%r{gems/mongoid_auto_increment})
  end
end