Auto merge of #5920 - bundler:colby/bundler-list, r=segiddins

implement new list command

### What was the end-user problem that led to this PR?

We're removing the `bundle show` command (which has been replaced with `bundle info`) but we should probably still have a command to list the gems in the bundle.

### What was your diagnosis of the problem?

`bundle show` has been marked as deprecated but a replacement for listing gems does not yet exist

### What is your fix for the problem, implemented in this PR?

Add a new `bundle list` (including `ls` alias) that prints the gems in the bundle, this was taken from #4754

1 files changed, 13 insertions, 1 deletions

diff --git a/lib/bundler/cli.rb b/lib/bundler/cli.rb
index 0d559a8f76..2adbac403e 100644
--- a/lib/bundler/cli.rb
+++ b/lib/bundler/cli.rb
@@ -261,7 +261,19 @@ module Bundler
       Show.new(options, gem_name).run
     end
     # TODO: 2.0 remove `bundle show`
-    map %w[list] => "show"
+
+    if Bundler.feature_flag.list_command?
+      desc "list", "List all gems in the bundle"
+      method_option "name-only", :type => :boolean, :banner => "print only the gem names"
+      def list
+        require "bundler/cli/list"
+        List.new(options).run
+      end
+
+      map %w[ls] => "list"
+    else
+      map %w[list] => "show"
+    end
 
     desc "info GEM [OPTIONS]", "Show information for the given gem"
     method_option "path", :type => :boolean, :banner => "Print full path to gem"