implement command `bundle plugin list`

4 files changed, 58 insertions, 0 deletions

diff --git a/lib/bundler/cli/plugin.rb b/lib/bundler/cli/plugin.rb
index 277822dafc..2019a4e10c 100644
--- a/lib/bundler/cli/plugin.rb
+++ b/lib/bundler/cli/plugin.rb
@@ -19,5 +19,10 @@ module Bundler
     def install(*plugins)
       Bundler::Plugin.install(plugins, options)
     end
+
+    desc "list", "List the installed plugins and available commands"
+    def list
+      Bundler::Plugin.list
+    end
   end
 end
diff --git a/lib/bundler/plugin.rb b/lib/bundler/plugin.rb
index 66f485ef8e..1e9c40fe49 100644
--- a/lib/bundler/plugin.rb
+++ b/lib/bundler/plugin.rb
@@ -45,6 +45,26 @@ module Bundler
       Bundler.ui.error "Failed to install plugin #{name}: #{e.message}\n  #{e.backtrace.join("\n ")}"
     end
 
+    # List installed plugins and commands
+    #
+    def list
+      installed_plugins = index.installed_plugins
+      if installed_plugins.any?
+        output = String.new
+        installed_plugins.each do |plugin|
+          output << "#{plugin}\n"
+          output << "-----\n"
+          index.plugin_commands(plugin).each do |command|
+            output << "  #{command}\n"
+          end
+          output << "\n"
+        end
+      else
+        output = "No plugins installed"
+      end
+      Bundler.ui.info output
+    end
+
     # Evaluates the Gemfile with a limited DSL and installs the plugins
     # specified by plugin method
     #
diff --git a/lib/bundler/plugin/index.rb b/lib/bundler/plugin/index.rb
index 8dde072f16..b9328d3177 100644
--- a/lib/bundler/plugin/index.rb
+++ b/lib/bundler/plugin/index.rb
@@ -95,6 +95,14 @@ module Bundler
         @plugin_paths[name]
       end
 
+      def installed_plugins
+        @plugin_paths.keys
+      end
+
+      def plugin_commands(plugin)
+        @commands.find_all {|_, n| n == plugins }.map(&:first)
+      end
+
       def source?(source)
         @sources.key? source
       end
diff --git a/spec/bundler/plugin_spec.rb b/spec/bundler/plugin_spec.rb
index 9796b580a3..40e71ab578 100644
--- a/spec/bundler/plugin_spec.rb
+++ b/spec/bundler/plugin_spec.rb
@@ -32,6 +32,31 @@ RSpec.describe Bundler::Plugin do
     allow(index).to receive(:register_plugin)
   end
 
+  describe "list command" do
+    let(:opts) { { "version" => "~> 1.0", "source" => "foo" } }
+
+    context "when no plugins are installed" do
+      before { allow(index).to receive(:installed_plugins) { [] } }
+      it "outputs no plugins installed" do
+        expect(Bundler.ui).to receive(:info).with("No plugins installed")
+        subject.list
+      end
+    end
+
+    context "with installed plugins" do
+      before do
+        allow(index).to receive(:installed_plugins) { %w[plug1 plug2] }
+        allow(index).to receive(:plugin_commands).with("plug1") { %w[c11 c12] }
+        allow(index).to receive(:plugin_commands).with("plug2") { %w[c21 c22] }
+      end
+      it "list plugins followed by commands" do
+        expected_output = "plug1\n-----\n  c11\n  c12\n\nplug2\n-----\n  c21\n  c22\n\n"
+        expect(Bundler.ui).to receive(:info).with(expected_output)
+        subject.list
+      end
+    end
+  end
+
   describe "install command" do
     let(:opts) { { "version" => "~> 1.0", "source" => "foo" } }