1 files changed, 95 insertions, 0 deletions
diff --git a/lib/bundler/plugin/installer.rb b/lib/bundler/plugin/installer.rb
new file mode 100644
index 0000000000..a50d0ceedd
--- /dev/null
+++ b/lib/bundler/plugin/installer.rb
@@ -0,0 +1,95 @@
+# 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, "bundler/plugin/installer/rubygems"
+      autoload :Git,      "bundler/plugin/installer/git"
+
+      def install(names, options)
+        version = options[:version] || [">= 0"]
+
+        if options[:git]
+          install_git(names, version, options)
+        else
+          sources = options[:source] || Bundler.rubygems.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.resolve_remotely!
+        specs = definition.specs
+
+        install_from_specs specs
+      end
+
+    private
+
+      def install_git(names, version, options)
+        uri = options.delete(:git)
+        options["uri"] = uri
+
+        source_list = SourceList.new
+        source_list.add_git_source(options)
+
+        # To support both sources
+        if options[:source]
+          source_list.add_rubygems_source("remotes" => options[:source])
+        end
+
+        deps = names.map {|name| Dependency.new name, version }
+
+        definition = Definition.new(nil, deps, source_list, true)
+        install_definition(definition)
+      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)
+        deps = names.map {|name| Dependency.new name, version }
+
+        source_list = SourceList.new
+        source_list.add_rubygems_source("remotes" => sources)
+
+        definition = Definition.new(nil, deps, source_list, true)
+        install_definition(definition)
+      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.install spec
+
+          paths[spec.name] = spec
+        end
+
+        paths
+      end
+    end
+  end
+end