Added plugin module with install functionality

6 files changed, 109 insertions, 2 deletions

diff --git a/lib/bundler.rb b/lib/bundler.rb
index ace1e7f3c4..45d735daa2 100644
--- a/lib/bundler.rb
+++ b/lib/bundler.rb
@@ -38,6 +38,7 @@ module Bundler
   autoload :MatchPlatform,          "bundler/match_platform"
   autoload :Mirror,                 "bundler/mirror"
   autoload :Mirrors,                "bundler/mirror"
+  autoload :Plugin,                 "bundler/plugin"
   autoload :RemoteSpecification,    "bundler/remote_specification"
   autoload :Resolver,               "bundler/resolver"
   autoload :Retry,                  "bundler/retry"
diff --git a/lib/bundler/cli.rb b/lib/bundler/cli.rb
index f2af5d71f7..75d4581e12 100644
--- a/lib/bundler/cli.rb
+++ b/lib/bundler/cli.rb
@@ -433,6 +433,10 @@ module Bundler
       Env.new.write($stdout)
     end
 
+    require "bundler/cli/plugin"
+    desc "plugin SUBCOMMAND ...ARGS", "manage the bundler plugins"
+    subcommand "plugin", Plugin
+
     # Reformat the arguments passed to bundle that include a --help flag
     # into the corresponding `bundle help #{command}` call
     def self.reformatted_help_args(args)
diff --git a/lib/bundler/cli/plugin.rb b/lib/bundler/cli/plugin.rb
new file mode 100644
index 0000000000..504f8726f9
--- /dev/null
+++ b/lib/bundler/cli/plugin.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+require "bundler/vendored_thor"
+module Bundler
+  class CLI::Plugin < Thor
+
+    desc "install PLUGIN", "Install the plugin from the source"
+    long_desc <<-D
+      Install a plugin named PLUGIN wither from the rubygems source provided (with --source option) or from a git source provided with (--git option).
+    D
+    method_option "source", :type=> :string, :default => nil, :banner =>
+      "Url of the RubyGems source to fetch the plugin from"
+    method_option "version", :type=> :string, :default => nil, :banner =>
+      "The version of the plugin to fetch from"
+    def install(plugin)
+      Bundler::Plugin.install(plugin, options)
+    end
+  end
+end
diff --git a/lib/bundler/plugin.rb b/lib/bundler/plugin.rb
new file mode 100644
index 0000000000..364401ded1
--- /dev/null
+++ b/lib/bundler/plugin.rb
@@ -0,0 +1,34 @@
+#frozen_string_literal: true
+
+module Bundler
+  class Plugin
+
+    class << self
+
+      def install(name, options)
+        require "bundler/plugin/installer.rb"
+
+        source = options[:source] || raise(ArgumentError, "You need to provide the source")
+        version = options[:version] || [">= 0"]
+
+        plugin_path = Installer.install(name, source, version)
+
+        puts plugin_path
+
+        Bundler.ui.info "Installed plugin #{name}"
+      rescue StandardError => e
+        Bundler.ui.error "Failed to install plugin #{name}: #{e.message}\n  #{e.backtrace.join("\n  ")}"
+        Bundler.ui.trace e
+      end
+
+
+      def root
+        @root ||= Bundler.user_bundle_path.join("plugin")
+      end
+
+      def cache
+        @cache ||= root.join "cache"
+      end
+    end
+  end
+end
diff --git a/lib/bundler/plugin/installer.rb b/lib/bundler/plugin/installer.rb
new file mode 100644
index 0000000000..8477ffad2c
--- /dev/null
+++ b/lib/bundler/plugin/installer.rb
@@ -0,0 +1,49 @@
+#frozen_string_literal: true
+
+module Bundler
+  class Plugin::Installer
+
+    # Installs the plugin and returns the path where the plugin was installed
+    def self.install(name, source, version = nil)
+      rg_source = Source::Rubygems.new "remotes" => source, :ignore_app_cache => true
+      rg_source.remote!
+      rg_source.dependency_names << name
+
+      dep = Dependency.new name, version
+
+      deps_proxies = [DepProxy.new(dep, GemHelpers.generic_local_platform)]
+      idx = rg_source.specs
+
+      specs = Resolver.resolve(deps_proxies, idx).materialize([dep])
+
+      raise InstallError, "Plugin dependencies are not supported currently" unless specs.size == 1
+
+      install_from_spec specs.first
+    end
+
+
+    # Installs the plugin from the provided spec and returns the path where the plugin was installed
+    def self.install_from_spec(spec)
+      raise ArgumentError, "Spec #{spec.name} doesn't have remote set" unless spec.remote
+
+      uri = spec.remote.uri
+      spec.fetch_platform
+
+      download_path = Plugin.cache
+
+      path = Bundler.rubygems.download_gem(spec, uri, download_path)
+
+      Bundler.rubygems.preserve_paths do
+        Bundler::RubyGemsGemInstaller.new(
+          path,
+          :install_dir         => Plugin.root.to_s,
+          :ignore_dependencies => true,
+          :wrappers            => true,
+          :env_shebang         => true
+
+        ).install.full_gem_path
+      end
+    end
+
+  end
+end
diff --git a/lib/bundler/source/rubygems.rb b/lib/bundler/source/rubygems.rb
index d8ca36e3f9..33e0e0be3f 100644
--- a/lib/bundler/source/rubygems.rb
+++ b/lib/bundler/source/rubygems.rb
@@ -21,7 +21,8 @@ module Bundler
         @dependency_names = []
         @allow_remote = false
         @allow_cached = false
-        @caches = [Bundler.app_cache, *Bundler.rubygems.gem_cache]
+        @caches = [*Bundler.rubygems.gem_cache]
+        @caches << Bundler.app_cache unless options[:ignore_app_cache] # To use this class for installing plugins
 
         Array(options["remotes"] || []).reverse_each {|r| add_remote(r) }
       end
@@ -80,7 +81,7 @@ module Bundler
           # sources, and large_idx.use small_idx is way faster than
           # small_idx.use large_idx.
           idx = @allow_remote ? remote_specs.dup : Index.new
-          idx.use(cached_specs, :override_dupes) if @allow_cached || @allow_remote
+          idx.use(cached_specs, :override_dupes) if @allow_cached || @allow_remote && !@options[:ignore_app_cache]
           idx.use(installed_specs, :override_dupes)
           idx
         end