Add I18n interface for mustache templates

This commit adds an interface that allows mustache templates to get I18n
translation strings, transform any arguments that may be present in
them, and then render them on the frontend.

This is our first real step to getting internationalizing the Gollum
frontend.

.github/workflows/test.yaml

@@ -0,0 +1,29 @@
+name: Ruby Build
+on: [push, pull_request]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby: [2.4.0, 2.6.0, 3.0.0, jruby-9.2.18.0]
+    steps:
+      - run: echo "The job was automatically triggered by a ${{ github.event_name }} event."
+      - run: echo "This job is now running on a ${{ runner.os }} server hosted by GitHub!"
+      - run: echo "The name of your branch is ${{ github.ref }} and your repository is ${{ github.repository }}."
+      - name: Check out repository code
+        uses: actions/checkout@v2
+      - run: echo "The ${{ github.repository }} repository has been cloned to the runner."
+      - run: echo "The workflow is now ready to test your code on the runner."
+      - name: List files in the repository
+        run: |
+          ls ${{ github.workspace }}
+      - uses: actions/setup-java@v2
+        with:
+          distribution: 'adopt'
+          java-version: '9'
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler-cache: true
+      - name: exec rake
+        run: bundle exec rake

.gitignore

@@ -8,3 +8,4 @@ Gemfile.lock
 .*
 !.sprockets*
 !lib/gollum/public/gollum/stylesheets/_styles.css
+!.github*

README.md

@@ -2,10 +2,11 @@ gollum -- A git-based Wiki
 ====================================
 
 [![Gem Version](https://badge.fury.io/rb/gollum.svg)](http://badge.fury.io/rb/gollum)
-[![Build Status](https://travis-ci.org/gollum/gollum.svg?branch=master)](https://travis-ci.org/gollum/gollum)
+![Build Status](https://github.com/gollum/gollum/actions/workflows/test.yaml/badge.svg)
 [![Open Source Helpers](https://www.codetriage.com/gollum/gollum/badges/users.svg)](https://www.codetriage.com/gollum/gollum)
 [![Cutting Edge Dependency Status](https://dometto-cuttingedge.herokuapp.com/github/gollum/gollum/svg 'Cutting Edge Dependency Status')](https://dometto-cuttingedge.herokuapp.com/github/gollum/gollum/info)
 
+
 **Gollum version 5.0 is out!** See [here](https://github.com/gollum/gollum/wiki/5.0-release-notes) for a list of changes and new features compared to Gollum version 4.x, and see some [Screenshots](https://github.com/gollum/gollum/wiki/Screenshots) of Gollum's features.
 
 ## DESCRIPTION
@@ -45,7 +46,7 @@ Installation examples for individual systems can be seen [here](https://github.c
 
 To run, simply:
 
-1. Run: `gollum /path/to/wiki`.
+1. Run: `gollum /path/to/wiki` where `/path/to/wiki` is an initialized Git repository.
 2. Open `http://localhost:4567` in your browser.
 
 See [below](#running-from-source) for information on running Gollum from source, as a Rack app, and more.

gollum.gemspec

@@ -39,6 +39,7 @@ Gem::Specification.new do |s|
   s.add_dependency 'rss', '~> 0.2.9'
   s.add_dependency 'therubyrhino', '~> 2.1.0'
   s.add_dependency 'webrick', '~> 1.7'
+  s.add_dependency 'i18n', '~> 1.8'
 
   s.add_development_dependency 'rack-test', '~> 0.6.3'
   s.add_development_dependency 'shoulda', '~> 3.6.0'

lib/gollum.rb

@@ -5,6 +5,7 @@ require 'digest/sha1'
 require 'ostruct'
 
 # external
+require 'i18n'
 require 'github/markup'
 require 'rhino' if RUBY_PLATFORM == 'java'
 
@@ -14,10 +15,13 @@ require File.expand_path('../gollum/uri_encode_component', __FILE__)
 module Gollum
   VERSION = '5.2.3'
 
+  ::I18n.available_locales = [:en]
+  ::I18n.load_path = Dir[File.expand_path("lib/gollum/locales") + "/*.yml"]
+
   def self.assets_path
     ::File.expand_path('gollum/public', ::File.dirname(__FILE__))
   end
-  
+
   class TemplateFilter
     @@filters = {}
 
@@ -32,5 +36,4 @@ module Gollum
       data
     end
   end
-
 end

lib/gollum/app.rb

@@ -1,4 +1,5 @@
-# ~*~ encoding: utf-8 ~*~
+# encoding: UTF-8
+
 require 'cgi'
 require 'sinatra'
 require 'sinatra/namespace'
@@ -14,6 +15,7 @@ require 'pathname'
 require 'gollum'
 require 'gollum/assets'
 require 'gollum/views/helpers'
+require 'gollum/views/helpers/locale_helpers'
 require 'gollum/views/layout'
 require 'gollum/views/editable'
 require 'gollum/views/has_page'
@@ -40,7 +42,7 @@ Gollum::set_git_max_filesize(190 * 10**6)
 # See the wiki.rb file for more details on wiki options
 
 module Precious
-  
+
   # For use with the --base-path option.
   class MapGollum
     def initialize(base_path)
@@ -63,12 +65,14 @@ module Precious
       @mg.call(env)
     end
   end
-  
+
   class App < Sinatra::Base
     register Mustache::Sinatra
     register Sinatra::Namespace
     include Precious::Helpers
-    
+
+    Encoding.default_external = "UTF-8"
+
     dir = File.dirname(File.expand_path(__FILE__))
 
     set :sprockets, ::Precious::Assets.sprockets(dir)
@@ -102,7 +106,7 @@ module Precious
       @critic_markup = settings.wiki_options[:critic_markup]
       @redirects_enabled = settings.wiki_options.fetch(:redirects_enabled, true)
       @per_page_uploads = settings.wiki_options[:per_page_uploads]
-      
+
       @wiki_title = settings.wiki_options.fetch(:title, 'Gollum Wiki')
 
       forbid unless @allow_editing || request.request_method == 'GET'
@@ -120,7 +124,7 @@ module Precious
       @use_static_assets = settings.wiki_options.fetch(:static, settings.environment != :development)
       @static_assets_path = settings.wiki_options.fetch(:static_assets_path, ::File.join(File.dirname(__FILE__), 'public/assets'))
       @mathjax_path = ::File.join(File.dirname(__FILE__), 'public/gollum/javascript/MathJax')
-      
+
       Sprockets::Helpers.configure do |config|
         config.environment = settings.sprockets
         config.environment.context_class.class_variable_set(:@@base_url, @base_url)
@@ -219,7 +223,7 @@ module Precious
 
       # AJAX calls only
       post '/upload_file' do
-        
+
         wiki = wiki_new
         halt 405 unless wiki.allow_uploads
 
@@ -235,7 +239,7 @@ module Precious
           dir.sub!(/^#{wiki.base_path}/, '') if wiki.base_path
           # remove base_url and gollum/* subpath if necessary
           dir.sub!(/^\/gollum\/[-\w]+\//, '')
-          # remove file extension 
+          # remove file extension
           dir.sub!(/#{::File.extname(dir)}$/, '')
           # revert escaped whitespaces
           dir.gsub!(/%20/, ' ')
@@ -317,7 +321,7 @@ module Precious
       end
 
       post '/edit/*' do
-        etag      = params[:etag]        
+        etag      = params[:etag]
         path      = "/#{clean_url(sanitize_empty_params(params[:path]))}"
         wiki      = wiki_new
         page      = wiki.page(::File.join(path, params[:page]))
@@ -327,7 +331,7 @@ module Precious
           # Signal edit collision and return the page's most recent version
           halt 412, {etag: page.sha, text_data: page.text_data}.to_json
         end
-        
+
         committer = Gollum::Committer.new(wiki, commit_message)
         commit    = { :committer => committer }
 
@@ -348,7 +352,7 @@ module Precious
           commit[:message] = "Deleted #{filepath}"
           wiki.delete_file(filepath, commit)
         end
-      end      
+      end
 
       get '/create/*' do
         forbid unless @allow_editing
@@ -625,7 +629,7 @@ module Precious
         end
       end
     end
-    
+
     def show_file(file)
       return unless file
       if file.on_disk?
@@ -683,4 +687,4 @@ module Precious
     end
 
   end
-end
+end

lib/gollum/views/helpers/locale_helpers.rb

@@ -0,0 +1,82 @@
+module Precious
+  module Views
+    module LocaleHelpers
+      NO_METHOD_MESSAGE = 'Argument must be a view method'
+      YAML_VARIABLE_REGEXP = /\%\{[\w]+\}/
+
+      # Returns all I18n translation strings for the current view class.
+      # This method support YAML arguments. For example:
+      #
+      #     last_edited: This content was last edited at %{date}.
+      #
+      # Where the `date` argument must be a method available on the current
+      # class.
+      #
+      # Use this interface within Mustache templates to render any user
+      # interface strings in the current locale. For example:
+      #
+      #     {{ t.last_edited }}
+      #
+      def t
+        autofill I18n.t(locale_klass_name)
+      end
+
+      private
+
+      # Recursively looks up I18n translation values and autofills any YAML
+      # arguments with the return value of the current class's matching method.
+      #
+      # When a translation value with an argument has no matching method, we
+      # then return that value transformed to include the `no_method_message`
+      #
+      def autofill(yaml)
+        yaml.map { |i18n_key, i18n_value|
+          if i18n_value.is_a? Hash
+            [i18n_key, autofill(i18n_value)]
+          elsif has_arguments?(i18n_value)
+            fill_argument_content(i18n_key, i18n_value)
+          else
+            [i18n_key, i18n_value]
+          end
+        }.to_h
+      end
+
+      def fill_argument_content(i18n_key, i18n_value)
+        i18n_value.gsub!(YAML_VARIABLE_REGEXP) do |argument|
+          method_name = argument.gsub(/[^\w]/, '')
+
+          next if method_name.nil?
+
+          begin
+            self.public_send(method_name)
+          rescue NoMethodError => error
+            no_method_message(method_name)
+          end
+        end
+
+        [i18n_key, i18n_value]
+      end
+
+      def has_arguments?(i18n_value)
+        i18n_value.match?(YAML_VARIABLE_REGEXP)
+      end
+
+      # Returns the current class name in a format that is acceptable in YAML.
+      # To summarize its function:
+      #
+      #     NameOfConstant => name_of_constant
+      #
+      def locale_klass_name
+        @locale_klass_name ||= self.class.name.gsub(/::/, '/').
+          gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2').
+          gsub(/([a-z\d])([A-Z])/,'\1_\2').
+          tr('-', '_').
+          downcase
+      end
+
+      def no_method_message(method_name, message = NO_METHOD_MESSAGE)
+        "[#{message}: #{method_name}]"
+      end
+    end
+  end
+end

lib/gollum/views/layout.rb

@@ -6,10 +6,11 @@ module Precious
       include Rack::Utils
       include Sprockets::Helpers
       include Precious::Views::AppHelpers
+      include Precious::Views::LocaleHelpers
       include Precious::Views::SprocketsHelpers
       include Precious::Views::RouteHelpers
       include Precious::Views::OcticonHelpers
-      
+
       alias_method :h, :escape_html
 
       attr_reader :name, :path

test/gollum/views/test_locale_helper.rb

@@ -0,0 +1,134 @@
+require_relative "../../helper"
+require_relative "../../../lib/gollum/views/helpers"
+
+describe Precious::Views::LocaleHelpers do
+  class TestClass < Mustache
+    include Precious::Views::LocaleHelpers
+
+    def author
+      "J.R.R."
+    end
+
+    def location
+      "Bloemfontein"
+    end
+  end
+
+  def setup
+    ::I18n.available_locales = [:en, :de]
+    ::I18n.load_path = Dir[File.expand_path("test/support/locales" + "/*.yml")]
+  end
+
+  def teardown
+    I18n.locale = :en
+  end
+
+  let(:dummy_instance) { TestClass.new }
+
+  describe "#t" do
+    describe "mustache usage" do
+      let(:subject) { dummy_instance.render(mustache_template) }
+
+      let(:mustache_template) { "{{ t.hello_world }}" }
+
+      describe "in the default locale" do
+        it "returns the translation string" do
+          _(subject).must_equal "Hello world"
+        end
+      end
+
+      describe "in the configured locale" do
+        it "returns the translation string" do
+          I18n.locale = :de
+
+          _(subject).must_equal "Hallo Welt"
+        end
+      end
+
+      describe "translations with YAML arguments" do
+        let(:mustache_template) { "{{ t.author_info.full }}" }
+
+        describe "in the default locale" do
+          it "autofills YAML arguments" do
+            _(subject).must_equal "Author J.R.R. is from Bloemfontein"
+          end
+        end
+
+        describe "in the configured locale" do
+          it "autofills YAML arguments" do
+            I18n.locale = :de
+
+            _(subject).must_equal "Autor J.R.R. ist vom Bloemfontein"
+          end
+        end
+      end
+
+      describe "translations with invalid arguments" do
+        let(:mustache_template) { "{{ t.has_invalid_argument }}" }
+
+        it "fails gracefully with embedded error message" do
+          expected_string = "Welcome to " \
+            "[#{TestClass::NO_METHOD_MESSAGE}: no_matching_method]"
+
+          _(subject).must_equal expected_string
+        end
+      end
+
+      describe "out of scope translations" do
+        let(:mustache_template) { "{{ t.never_called }}" }
+
+        it "does not include translation keys from other classes" do
+          _(subject).must_be_empty
+        end
+      end
+
+      describe "missing translations" do
+        let(:mustache_template) { "{{ t.nested.nonexistent_key }}" }
+
+        it "outputs an empty string" do
+          _(subject).must_be_empty
+        end
+      end
+    end
+
+    describe "usage" do
+      let(:subject) { dummy_instance.t }
+
+      it "returns a hash" do
+        _(subject).must_be_kind_of Hash
+      end
+
+      it "returns translation keys under 'test_class'" do
+        i18n_keys = I18n.t("test_class").keys
+
+        _(subject.keys).must_equal i18n_keys
+      end
+
+      it "does not return translation keys under other classes" do
+        other_i18n_keys = I18n.t("nonexistant_test_class").keys
+
+        _(subject.keys).wont_include other_i18n_keys
+      end
+
+      it "returns nested keys" do
+        nested_keys = subject[:author_info].keys
+
+        _(nested_keys).must_equal [:full]
+      end
+
+      describe "auto-filled YAML arguments" do
+        let(:subject) { dummy_instance.t[:author_info][:full] }
+
+        it "auto-fills in the default locale" do
+          _(subject).must_equal "Author J.R.R. is from Bloemfontein"
+        end
+
+        it "auto-fills in a configured locale" do
+          I18n.locale = :de
+
+          _(subject).must_equal "Autor J.R.R. ist vom Bloemfontein"
+        end
+      end
+    end
+  end
+end

test/helper.rb

@@ -5,6 +5,7 @@ require 'shoulda'
 require 'mocha/setup'
 require 'fileutils'
 require 'minitest/reporters'
+require 'minitest/spec'
 require 'twitter_cldr'
 require 'tmpdir'
 
@@ -93,4 +94,4 @@ def context(*args, &block)
   klass.class_eval &block
 end
 
-$contexts = []
+$contexts = []

test/support/locales/de.yml

@@ -0,0 +1,8 @@
+de:
+  test_class:
+    author_info:
+      full: Autor %{author} ist vom %{location}
+    has_invalid_argument: Willkommen in %{no_matching_method}
+    hello_world: Hallo Welt
+  nonexistant_test_class:
+    never_called: Nie angerufen

test/support/locales/en.yml

@@ -0,0 +1,8 @@
+en:
+  test_class:
+    author_info:
+      full: Author %{author} is from %{location}
+    has_invalid_argument: Welcome to %{no_matching_method}
+    hello_world: Hello world
+  nonexistant_test_class:
+    never_called: Never called

test/test_migrate.rb

@@ -44,7 +44,7 @@ def load_script(**args)
   end  
 end
 
-unless ENV['TRAVIS']
+unless ENV['CI']
 
   context '4.x -> 5.x tag migrator' do
     include Rack::Test::Methods