Merge pull request #2865 from jekyll/some-kind-of-bundler-thingy

Rakefile

@@ -146,10 +146,14 @@ namespace :site do
 
     # Generate the site in server mode.
     puts "Running Jekyll..."
-    Jekyll::Commands::Serve.process({
+    options = {
       "source"      => File.expand_path("site"),
-      "destination" => File.expand_path("site/_site")
+      "destination" => File.expand_path("site/_site"),
-    })
+      "watch"       => true,
+      "serving"     => true
+    }
+    Jekyll::Commands::Build.process(options)
+    Jekyll::Commands::Serve.process(options)
   end
 
   desc "Generate the site"

bin/jekyll

@@ -13,6 +13,8 @@ require 'mercenary'
   end
 end
 
+Jekyll::PluginManager.require_from_bundler
+
 Jekyll::Deprecator.process(ARGV)
 
 Mercenary.program(:jekyll) do |p|

features/plugins.feature

@@ -0,0 +1,34 @@
+Feature: Configuring and using plugins
+  As a hacker
+  I want to specify my own plugins that can modify Jekyll's behaviour
+
+  Scenario: Add a gem-based plugin
+    Given I have an "index.html" file that contains "Whatever"
+    And I have a configuration file with "gems" set to "[jekyll_test_plugin]"
+    When I run jekyll build
+    Then the _site directory should exist
+    And I should see "Whatever" in "_site/index.html"
+    And I should see "this is a test" in "_site/test.txt"
+
+  Scenario: Add an empty whitelist to restrict all gems
+    Given I have an "index.html" file that contains "Whatever"
+    And I have a configuration file with:
+      | key       | value                |
+      | gems      | [jekyll_test_plugin] |
+      | whitelist | []                   |
+    When I run jekyll build --safe
+    Then the _site directory should exist
+    And I should see "Whatever" in "_site/index.html"
+    And the "_site/test.txt" file should not exist
+
+  Scenario: Add a whitelist to restrict some gems but allow others
+    Given I have an "index.html" file that contains "Whatever"
+    And I have a configuration file with:
+      | key       | value                                              |
+      | gems      | [jekyll_test_plugin, jekyll_test_plugin_malicious] |
+      | whitelist | [jekyll_test_plugin]                               |
+    When I run jekyll build --safe
+    Then the _site directory should exist
+    And I should see "Whatever" in "_site/index.html"
+    And the "_site/test.txt" file should exist
+    And I should see "this is a test" in "_site/test.txt"

features/site_configuration.feature

@@ -243,37 +243,6 @@ Feature: Site configuration
     And I should see "Post Layout: <p>content for entry1.</p>" in "_site/2007/12/31/entry1.html"
     And I should see "Post Layout: <p>content for entry2.</p>" in "_site/2020/01/31/entry2.html"
 
-  Scenario: Add a gem-based plugin
-    Given I have an "index.html" file that contains "Whatever"
-    And I have a configuration file with "gems" set to "[jekyll_test_plugin]"
-    When I run jekyll build
-    Then the _site directory should exist
-    And I should see "Whatever" in "_site/index.html"
-    And I should see "this is a test" in "_site/test.txt"
-
-  Scenario: Add an empty whitelist to restrict all gems
-    Given I have an "index.html" file that contains "Whatever"
-    And I have a configuration file with:
-      | key       | value                |
-      | gems      | [jekyll_test_plugin] |
-      | whitelist | []                   |
-    When I run jekyll build --safe
-    Then the _site directory should exist
-    And I should see "Whatever" in "_site/index.html"
-    And the "_site/test.txt" file should not exist
-
-  Scenario: Add a whitelist to restrict some gems but allow others
-    Given I have an "index.html" file that contains "Whatever"
-    And I have a configuration file with:
-      | key       | value                                              |
-      | gems      | [jekyll_test_plugin, jekyll_test_plugin_malicious] |
-      | whitelist | [jekyll_test_plugin]                               |
-    When I run jekyll build --safe
-    Then the _site directory should exist
-    And I should see "Whatever" in "_site/index.html"
-    And the "_site/test.txt" file should exist
-    And I should see "this is a test" in "_site/test.txt"
-
   Scenario: arbitrary file reads via layouts
     Given I have an "index.html" page with layout "page" that contains "FOO"
     And I have a "_config.yml" file that contains "layouts: '../../../../../../../../../../../../../../usr/include'"

features/step_definitions/jekyll_steps.rb

@@ -146,6 +146,13 @@ When /^I run jekyll(.*)$/ do |args|
   end
 end
 
+When /^I run bundle(.*)$/ do |args|
+  status = run_bundle(args)
+  if args.include?("--verbose") || ENV['DEBUG']
+    puts jekyll_run_output
+  end
+end
+
 When /^I change "(.*)" to contain "(.*)"$/ do |file, text|
   File.open(file, 'a') do |f|
     f.write(text)

features/support/env.rb

@@ -21,11 +21,19 @@ def jekyll_run_output
   File.read(jekyll_output_file) if File.file?(jekyll_output_file)
 end
 
+def run_bundle(args)
+  child = run_in_shell('bundle', *args.strip.split(' '))
+end
+
 def run_jekyll(args)
-  child = POSIX::Spawn::Child.new JEKYLL_PATH, *args.strip.split(' '), "--trace", :out => [JEKYLL_COMMAND_OUTPUT_FILE, "w"]
+  child = run_in_shell(JEKYLL_PATH, *args.strip.split(' '), "--trace")
   child.status.exitstatus == 0
 end
 
+def run_in_shell(*args)
+  POSIX::Spawn::Child.new *args, :out => [JEKYLL_COMMAND_OUTPUT_FILE, "w"]
+end
+
 def slug(title)
   if title
     title.downcase.gsub(/[^\w]/, " ").strip.gsub(/\s+/, '-')

lib/jekyll/plugin_manager.rb

@@ -17,6 +17,7 @@ module Jekyll
     def conscientious_require
       require_plugin_files
       require_gems
+      self.class.require_from_bundler
     end
 
     # Require each of the gem plugins specified.
@@ -25,11 +26,26 @@ module Jekyll
     def require_gems
       site.gems.each do |gem|
         if plugin_allowed?(gem)
+          Jekyll.logger.debug("PluginManager:", "Requiring #{gem}")
           require gem
         end
       end
     end
 
+    def self.require_from_bundler
+      if ENV["JEKYLL_NO_BUNDLER_REQUIRE"]
+        false
+      else
+        require "bundler"
+        required_gems = Bundler.require(:jekyll_plugins)
+        Jekyll.logger.debug("PluginManager:", "Required #{required_gems.map(&:name).join(', ')}")
+        ENV["JEKYLL_NO_BUNDLER_REQUIRE"] = "true"
+        true
+      end
+    rescue LoadError
+      false
+    end
+
     # Check whether a gem plugin is allowed to be used during this build.
     #
     # gem_name - the name of the gem

site/_docs/plugins.md

@@ -25,7 +25,7 @@ having to modify the Jekyll source itself.
 
 ## Installing a plugin
 
-You have 2 options for installing plugins:
+You have 3 options for installing plugins:
 
 1. In your site source root, make a `_plugins` directory. Place your plugins here.
     Any file ending in `*.rb` inside this directory will be loaded before Jekyll
@@ -35,6 +35,12 @@ You have 2 options for installing plugins:
 
         gems: [jekyll-test-plugin, jekyll-jsonify, jekyll-assets]
         # This will require each of these gems automatically.
+3. Add the relevant plugins to a Bundler group in your `Gemfile`. An
+    example:
+
+        group :jekyll_plugins do
+          gem "my-jekyll-plugin"
+        end
 
 <div class="note info">
   <h5>
@@ -247,6 +253,67 @@ In our example, `UpcaseConverter#matches` checks if our filename extension is
 simply uppercasing the entire content string. Finally, when it saves the page,
 it will do so with a `.html` extension.
 
+## Command
+
+As of version 2.5.0, Jekyll can be extended with plugins which provide
+subcommands for the `jekyll` executable. This is possible by including the
+relevant plugins in a `Gemfile` group called `:jekyll_plugins`:
+
+{% highlight ruby %}
+group :jekyll_plugins do
+  gem "my_fancy_jekyll_plugin"
+end
+{% endhighlight %}
+
+Each `Command` must be a subclass of the `Jekyll::Command` class and must
+contain one class method: `init_with_program`. An example:
+
+{% highlight ruby %}
+class MyNewCommand < Jekyll::Command
+  class << self
+    def init_with_program(prog)
+      prog.command(:new) do |c|
+        c.syntax "new [options]"
+        c.description 'Create a new Jekyll site.'
+
+        c.option 'dest', '-d DEST, 'Where the site should go.'
+
+        c.action do |args, options|
+          Jekyll::Site.new_site_at(options['dest'])
+        end
+      end
+    end
+  end
+end
+{% endhighlight %}
+
+Commands should implement this single class method:
+
+<div class="mobile-side-scroller">
+<table>
+  <thead>
+    <tr>
+      <th>Method</th>
+      <th>Description</th>
+    </tr>
+  </thead>
+  <tbody>
+    <tr>
+      <td>
+        <p><code>init_with_program</code></p>
+      </td>
+      <td><p>
+        This method accepts one parameter, the
+        <code><a href="http://github.com/jekyll/mercenary#readme">Mercenary::Program</a></code>
+        instance, which is the Jekyll program itself. Upon the program,
+        commands may be created using the above syntax. For more details,
+        visit the Mercenary repository on GitHub.com.
+      </p></td>
+    </tr>
+  </tbody>
+</table>
+</div>
+
 ## Tags
 
 If you’d like to include custom liquid tags in your site, you can do so by

test/helper.rb

@@ -58,6 +58,13 @@ class Test::Unit::TestCase
     File.open("#{path}/index.html", "w"){ |f| f.write("I was previously generated.") }
   end
 
+  def with_env(key, value)
+    old_value = ENV[key]
+    ENV[key] = value
+    yield
+    ENV[key] = old_value
+  end
+
   def capture_stdout
     $old_stdout = $stdout
     $stdout = StringIO.new

test/test_plugin_manager.rb

@@ -0,0 +1,16 @@
+require 'helper'
+
+class TestPluginManager < Test::Unit::TestCase
+  def test_requiring_from_bundler
+    with_env("JEKYLL_NO_BUNDLER_REQUIRE", nil) do
+      Jekyll::PluginManager.require_from_bundler
+      assert ENV["JEKYLL_NO_BUNDLER_REQUIRE"], 'Gemfile plugins were not required.'
+    end
+  end
+
+  def test_blocking_requiring_from_bundler
+    with_env("JEKYLL_NO_BUNDLER_REQUIRE", "true") do
+      assert_equal false, Jekyll::PluginManager.require_from_bundler, "Gemfile plugins were required but shouldn't have been"
+    end
+  end
+end