Open changelog url when o key is pressed (#32)

Add a key binding for opening the changelog URL. Now you can navigate to
a gem with up/down and press `o` (lower-case letter o) to open the URL
in your default web browser.

This implementation depends on the
[launchy](https://github.com/copiousfreetime/launchy) gem. Refer to its
README for information on configuring which browser is used.

TODO

- [x] PR description
- [x] Unit test
- [x] Update README image
- [x] Fix failing Ruby head test due to undeclared launchy →
childprocess → logger dependency

Closes #30

bundle_update_interactive.gemspec

@@ -30,6 +30,7 @@ Gem::Specification.new do |spec|
   # Runtime dependencies
   spec.add_dependency "bundler", "~> 2.0"
   spec.add_dependency "bundler-audit", ">= 0.9.1"
+  spec.add_dependency "launchy", ">= 2.5.0"
   spec.add_dependency "pastel", ">= 0.8.0"
   spec.add_dependency "tty-prompt", ">= 0.23.1"
   spec.add_dependency "tty-screen", ">= 0.8.2"

lib/bundle_update_interactive/cli/multi_select.rb

@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require "launchy"
 require "pastel"
 require "tty/prompt"
 require "tty/screen"
@@ -8,6 +9,7 @@ class BundleUpdateInteractive::CLI
   class MultiSelect
     class List < TTY::Prompt::MultiList
       def initialize(prompt, **options)
+        @opener = options.delete(:opener)
         defaults = {
           cycle: true,
           help_color: :itself.to_proc,
@@ -34,20 +36,30 @@ def keypress(event)
         when "j", "n" then keydown
         when "a" then select_all
         when "r" then reverse_selection
+        when "o" then opener&.call(choices[@active - 1].value)
         end
       end
+
+      private
+
+      attr_reader :opener
     end
 
     def self.prompt_for_gems_to_update(outdated_gems, prompt: nil)
       table = Table.new(outdated_gems)
       title = "#{outdated_gems.length} gems can be updated."
-      chosen = new(title: title, table: table, prompt: prompt).prompt
+      opener = lambda do |gem|
+        url = outdated_gems[gem].changelog_uri
+        Launchy.open(url) unless url.nil?
+      end
+      chosen = new(title: title, table: table, prompt: prompt, opener: opener).prompt
       outdated_gems.slice(*chosen)
     end
 
-    def initialize(title:, table:, prompt: nil)
+    def initialize(title:, table:, opener: nil, prompt: nil)
       @title = title
       @table = table
+      @opener = opener
       @tty_prompt = prompt || TTY::Prompt.new(
         interrupt: lambda {
           puts
@@ -59,16 +71,16 @@ def initialize(title:, table:, prompt: nil)
 
     def prompt
       choices = table.gem_names.to_h { |name| [table.render_gem(name), name] }
-      tty_prompt.invoke_select(List, title, choices, help: help)
+      tty_prompt.invoke_select(List, title, choices, help: help, opener: opener)
     end
 
     private
 
-    attr_reader :pastel, :table, :tty_prompt, :title
+    attr_reader :pastel, :table, :opener, :tty_prompt, :title
 
     def help
       [
-        pastel.dim("\nPress <space> to select, ↑/↓ move, <a> all, <r> reverse, <enter> to finish."),
+        pastel.dim("\nPress <space> to select, ↑/↓ move, <a> all, <r> reverse, <o> open url, <enter> to finish."),
         "\n    ",
         table.render_header
       ].join

lib/bundle_update_interactive/outdated_gem.rb

@@ -10,7 +10,7 @@ class OutdatedGem
                   :updated_version,
                   :updated_git_version
 
-    attr_writer :rubygems_source, :vulnerable
+    attr_writer :changelog_uri, :rubygems_source, :vulnerable
 
     def initialize(**attrs)
       @vulnerable = nil

test/bundle_update_interactive/cli/multi_select_test.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require "test_helper"
+require "launchy"
 require "tty/prompt/test"
 
 class BundleUpdateInteractive::CLI
@@ -12,9 +13,9 @@ class MultiSelectTest < Minitest::Test
 
     def setup
       @outdated_gems = {
-        "a" => build(:outdated_gem, name: "a", rubygems_source: false),
-        "b" => build(:outdated_gem, name: "b", rubygems_source: false),
-        "c" => build(:outdated_gem, name: "c", rubygems_source: false)
+        "a" => build(:outdated_gem, name: "a", changelog_uri: nil),
+        "b" => build(:outdated_gem, name: "b", changelog_uri: "https://b.example.com/"),
+        "c" => build(:outdated_gem, name: "c", changelog_uri: "https://c.example.com/")
       }
     end
 
@@ -66,6 +67,18 @@ def test_pressing_ctrl_r_has_no_effect
       assert_empty selected
     end
 
+    def test_pressing_down_then_o_opens_changelog_uri_of_second_gem_in_browser
+      Launchy.expects(:open).with("https://b.example.com/").once
+
+      use_menu_with_keypress ARROW_DOWN, "o"
+    end
+
+    def test_pressing_o_for_gem_with_no_changelog_does_nothing
+      Launchy.expects(:open).never
+
+      use_menu_with_keypress "o"
+    end
+
     private
 
     def use_menu_with_keypress(*keys)