Restore gem query

Manifest.txt

@@ -356,6 +356,7 @@ lib/rubygems/commands/outdated_command.rb
 lib/rubygems/commands/owner_command.rb
 lib/rubygems/commands/pristine_command.rb
 lib/rubygems/commands/push_command.rb
+lib/rubygems/commands/query_command.rb
 lib/rubygems/commands/rdoc_command.rb
 lib/rubygems/commands/search_command.rb
 lib/rubygems/commands/server_command.rb
@@ -598,6 +599,7 @@ test/rubygems/test_gem_commands_outdated_command.rb
 test/rubygems/test_gem_commands_owner_command.rb
 test/rubygems/test_gem_commands_pristine_command.rb
 test/rubygems/test_gem_commands_push_command.rb
+test/rubygems/test_gem_commands_query_command.rb
 test/rubygems/test_gem_commands_search_command.rb
 test/rubygems/test_gem_commands_server_command.rb
 test/rubygems/test_gem_commands_setup_command.rb

lib/rubygems/commands/query_command.rb

@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+require 'rubygems/command'
+require 'rubygems/query_utils'
+require 'rubygems/deprecate'
+
+class Gem::Commands::QueryCommand < Gem::Command
+
+  extend Gem::Deprecate
+  deprecate_command(2020, 12)
+
+  include Gem::QueryUtils
+
+  def initialize(name = 'query',
+                 summary = 'Query gem information in local or remote repositories')
+    super name, summary,
+         :name => //, :domain => :local, :details => false, :versions => true,
+         :installed => nil, :version => Gem::Requirement.default
+
+    add_option('-n', '--name-matches REGEXP',
+               'Name of gem(s) to query on matches the',
+               'provided REGEXP') do |value, options|
+      options[:name] = /#{value}/i
+    end
+
+    add_query_options
+  end
+
+end