1 files changed, 123 insertions, 0 deletions
diff --git a/lib/bundler/plugin/installer.rb b/lib/bundler/plugin/installer.rb
new file mode 100644
index 0000000000..9be8b36843
--- /dev/null
+++ b/lib/bundler/plugin/installer.rb
@@ -0,0 +1,123 @@
+# frozen_string_literal: true
+
+module Bundler
+  # Handles the installation of plugin in appropriate directories.
+  #
+  # This class is supposed to be wrapper over the existing gem installation infra
+  # but currently it itself handles everything as the Source's subclasses (e.g. Source::RubyGems)
+  # are heavily dependent on the Gemfile.
+  module Plugin
+    class Installer
+      autoload :Rubygems, File.expand_path("installer/rubygems", __dir__)
+      autoload :Git,      File.expand_path("installer/git", __dir__)
+      autoload :Path, File.expand_path("installer/path", __dir__)
+
+      def install(names, options)
+        check_sources_consistency!(options)
+
+        version = options[:version] || [">= 0"]
+
+        if options[:git]
+          install_git(names, version, options)
+        elsif options[:path]
+          install_path(names, version, options[:path])
+        else
+          sources = options[:source] || Gem.sources
+          install_rubygems(names, version, sources)
+        end
+      end
+
+      # Installs the plugin from Definition object created by limited parsing of
+      # Gemfile searching for plugins to be installed
+      #
+      # @param [Definition] definition object
+      # @return [Hash] map of names to their specs they are installed with
+      def install_definition(definition)
+        def definition.lock(*); end
+        definition.remotely!
+        specs = definition.specs
+
+        install_from_specs specs
+      end
+
+      private
+
+      def check_sources_consistency!(options)
+        if (options.keys & [:source, :git, :path]).length > 1
+          raise InvalidOption, "Only one of --source, --git, or --path may be specified"
+        end
+
+        if (options.key?(:branch) || options.key?(:ref)) && !options.key?(:git)
+          raise InvalidOption, "--#{options.key?(:branch) ? "branch" : "ref"} can only be used with git sources"
+        end
+
+        if options.key?(:branch) && options.key?(:ref)
+          raise InvalidOption, "--branch and --ref can't be both specified"
+        end
+      end
+
+      def install_git(names, version, options)
+        source_list = SourceList.new
+        source = source_list.add_git_source({ "uri" => options[:git],
+                                              "branch" => options[:branch],
+                                              "ref" => options[:ref] })
+
+        install_all_sources(names, version, source_list, source)
+      end
+
+      def install_path(names, version, path)
+        source_list = SourceList.new
+        source = source_list.add_path_source({ "path" => path, "root_path" => SharedHelpers.pwd })
+
+        install_all_sources(names, version, source_list, source)
+      end
+
+      # Installs the plugin from rubygems source and returns the path where the
+      # plugin was installed
+      #
+      # @param [String] name of the plugin gem to search in the source
+      # @param [Array] version of the gem to install
+      # @param [String, Array<String>] source(s) to resolve the gem
+      #
+      # @return [Hash] map of names to the specs of plugins installed
+      def install_rubygems(names, version, sources)
+        source_list = SourceList.new
+
+        Array(sources).each {|remote| source_list.add_global_rubygems_remote(remote) }
+
+        install_all_sources(names, version, source_list)
+      end
+
+      def install_all_sources(names, version, source_list, source = nil)
+        deps = names.map {|name| Dependency.new(name, version, { "source" => source }) }
+
+        Bundler.configure_gem_home_and_path(Plugin.root)
+
+        Bundler.settings.temporary(deployment: false, frozen: false) do
+          definition = Definition.new(nil, deps, source_list, true)
+
+          install_definition(definition)
+        end
+      end
+
+      # Installs the plugins and deps from the provided specs and returns map of
+      # gems to their paths
+      #
+      # @param specs to install
+      #
+      # @return [Hash] map of names to the specs
+      def install_from_specs(specs)
+        paths = {}
+
+        specs.each do |spec|
+          spec.source.download(spec)
+          spec.source.install(spec)
+
+          paths[spec.name] = spec
+        end
+
+        paths
+      end
+    end
+  end
+end