[rubygems/rubygems] Add --json bundle-outdated flag to produce json-parseable output

https://github.com/rubygems/rubygems/commit/65efa44bc0

lib/bundler/cli.rb

@@ -420,6 +420,7 @@ module Bundler
     method_option "filter-patch", :type => :boolean, :banner => "Only list patch newer versions"
     method_option "parseable", :aliases => "--porcelain", :type => :boolean, :banner =>
       "Use minimal formatting for more parseable output"
+    method_option "json", :type => :boolean, :banner => "Produce parseable json output"
     method_option "only-explicit", :type => :boolean, :banner =>
       "Only list gems specified in your Gemfile, not their dependencies"
     def outdated(*gems)

lib/bundler/cli/outdated.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require "json"
+
 module Bundler
   class CLI::Outdated
     attr_reader :options, :gems, :options_include_groups, :filter_options_patch, :sources, :strict
@@ -53,13 +55,13 @@ module Bundler
         options[:local] ? definition.resolve_with_cache! : definition.resolve_remotely!
       end
 
-      if options[:parseable]
+      if options[:parseable] || options[:json]
         Bundler.ui.silence(&definition_resolution)
       else
         definition_resolution.call
       end
 
-      Bundler.ui.info ""
+      Bundler.ui.info "" unless options[:json]
 
       # Loop through the current specs
       gemfile_specs, dependency_specs = current_specs.partition do |spec|
@@ -98,7 +100,9 @@ module Bundler
       end
 
       if outdated_gems.empty?
-        unless options[:parseable]
+        if options[:json]
+          print_gems_json([])
+        elsif !options[:parseable]
           Bundler.ui.info(nothing_outdated_message)
         end
       else
@@ -108,7 +112,9 @@ module Bundler
           outdated_gems
         end
 
-        if options[:parseable]
+        if options[:json]
+          print_gems_json(relevant_outdated_gems)
+        elsif options[:parseable]
           print_gems(relevant_outdated_gems)
         else
           print_gems_table(relevant_outdated_gems)
@@ -173,6 +179,20 @@ module Bundler
       end
     end
 
+    def print_gems_json(gems_list)
+      data = gems_list.map do |gem|
+        gem_data_for(
+          gem[:current_spec],
+          gem[:active_spec],
+          gem[:dependency],
+          gem[:groups]
+        )
+      end
+
+      data = { :outdated_count => gems_list.count, :outdated_gems => data }
+      Bundler.ui.info data.to_json
+    end
+
     def print_gems_table(gems_list)
       data = gems_list.map do |gem|
         gem_column_for(
@@ -212,6 +232,26 @@ module Bundler
       Bundler.ui.info output_message.rstrip
     end
 
+    def gem_data_for(current_spec, active_spec, dependency, groups)
+      {
+        :current_spec => spec_data_for(current_spec),
+        :active_spec => spec_data_for(active_spec),
+        :dependency => dependency&.to_s,
+        :groups => (groups || "").split(", "),
+      }
+    end
+
+    def spec_data_for(spec)
+      {
+        :name => spec.name,
+        :version => spec.version.to_s,
+        :platform => spec.platform,
+        :source => spec.source.to_s,
+        :required_ruby_version => spec.required_ruby_version.to_s,
+        :required_rubygems_version => spec.required_rubygems_version.to_s,
+      }
+    end
+
     def gem_column_for(current_spec, active_spec, dependency, groups)
       current_version = "#{current_spec.version}#{current_spec.git_version}"
       spec_version = "#{active_spec.version}#{active_spec.git_version}"

spec/bundler/bundler/cli_spec.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require "bundler/cli"
+require "json"
 
 RSpec.describe "bundle executable" do
   it "returns non-zero exit status when passed unrecognized options" do
@@ -154,6 +155,26 @@ RSpec.describe "bundle executable" do
       end
     end
 
+    context "with --json" do
+      let(:flags) { "--json" }
+
+      it "prints json output data when there are outdated gems" do
+        run_command
+        out_data = JSON.parse(out)
+        expect(out_data.keys).to contain_exactly("outdated_count", "outdated_gems")
+        expect(out_data["outdated_count"]).to eq(1)
+        expect(out_data["outdated_gems"].length).to eq(1)
+
+        gem_data = out_data["outdated_gems"].first
+        expect(gem_data).to include({
+          "current_spec" => hash_including("name" => "rack", "version" => "0.9.1"),
+          "active_spec" => hash_including("name" => "rack", "version" => "1.0.0"),
+          "dependency" => "rack (= 0.9.1)",
+          "groups" => ["default"],
+        })
+      end
+    end
+
     context "with --parseable" do
       let(:flags) { "--parseable" }