Create Komponent::ComponentRenderer

.simplecov

@@ -0,0 +1,10 @@
+require 'coveralls'
+
+SimpleCov.minimum_coverage 90
+SimpleCov.formatter = Coveralls::SimpleCov::Formatter
+
+SimpleCov.start do
+  add_filter "/fixtures/"
+  add_filter "/test/"
+  add_filter "/features/"
+end

Gemfile

@@ -14,4 +14,6 @@ gem "rubocop", require: false
 group :test do
   gem "aruba"
   gem "cucumber"
+  gem "simplecov", require: false
+  gem "coveralls", require: false
 end

README.md

@@ -2,6 +2,7 @@
 [![Build Status](https://travis-ci.org/komposable/komponent.svg?branch=master)](https://travis-ci.org/komposable/komponent)
 [![Gem](https://img.shields.io/gem/v/komponent.svg)](https://github.com/komposable/komponent)
 [![Dependency Status](https://beta.gemnasium.com/badges/github.com/komposable/komponent.svg)](https://beta.gemnasium.com/projects/github.com/komposable/komponent)
+[![Coverage Status](https://coveralls.io/repos/github/komposable/komponent/badge.svg?branch=master)](https://coveralls.io/github/komposable/komponent?branch=master)
 
 **Komponent** implements an opinionated way of organizing front-end code in Ruby on Rails, based on _components_.
 

Rakefile

@@ -13,6 +13,7 @@ namespace :test do
     t.libs << "lib"
     t.test_files = FileList["test/**/*_test.rb"]
     t.verbose = true
+    t.warning = false
   end
 
   Cucumber::Rake::Task.new(:cucumber) do |t|

features/support/env.rb

@@ -0,0 +1,3 @@
+# frozen_string_literal: true
+
+require 'simplecov'

fixtures/my_app/config/application.rb

@@ -12,5 +12,6 @@
 
 module MyApp
   class Application < Rails::Application
+    config.i18n.load_path += Dir[config.root.join('frontend/components/**/*.yml')]
   end
 end

fixtures/my_app/frontend/components/foo/_foo.html.erb

@@ -0,0 +1 @@
+<div class="foo"><%= properties[:bar] %></div>

fixtures/my_app/frontend/components/foo/foo.js

@@ -0,0 +1 @@
+import "./foo.scss";

fixtures/my_app/frontend/components/foo/foo.scss

@@ -0,0 +1,2 @@
+.foo {
+}

fixtures/my_app/frontend/components/foo/foo_component.rb

@@ -0,0 +1,5 @@
+module FooComponent
+  extend ComponentHelper
+
+  property :bar, default: "Foobar"
+end

fixtures/my_app/frontend/components/hello/_hello.html.erb

@@ -0,0 +1 @@
+<div class="hello"><%= t(".hello") %></div>

fixtures/my_app/frontend/components/hello/hello.en.yml

@@ -0,0 +1,3 @@
+en:
+  hello_component:
+    hello: "Hello"

fixtures/my_app/frontend/components/hello/hello.fr.yml

@@ -0,0 +1,3 @@
+fr:
+  hello_component:
+    hello: "Bonjour"

fixtures/my_app/frontend/components/hello/hello.js

@@ -0,0 +1 @@
+import "./hello.scss";

fixtures/my_app/frontend/components/hello/hello.scss

@@ -0,0 +1,2 @@
+.hello {
+}

fixtures/my_app/frontend/components/hello/hello_component.rb

@@ -0,0 +1,3 @@
+module HelloComponent
+  extend ComponentHelper
+end

lib/komponent/core/component_helper.rb → lib/komponent/component_helper.rb

@@ -9,10 +9,5 @@ def property(name, options = {})
 
   def self.extended(component)
     component.properties = {}
-    component.class_eval do
-      def block_given_to_component?
-        @block_given_to_component.present?
-      end
-    end
   end
 end

lib/komponent/component_renderer.rb

@@ -0,0 +1,65 @@
+# frozen_string_literal: true
+
+module Komponent
+  class Renderer
+    attr_reader :context
+
+    def initialize(controller)
+      @context = controller.view_context.dup
+      @view_renderer = @context.view_renderer = @context.view_renderer.dup
+      @lookup_context = @view_renderer.lookup_context = @view_renderer.lookup_context.dup
+    end
+
+    def render(component, locals = {}, &block)
+      parts = component.split("/")
+      component_name = parts.join("_")
+
+      component_module_path = resolved_component_path(component)
+        .join("#{component_name}_component")
+      require_dependency(component_module_path)
+      component_module = "#{component_name}_component".camelize.constantize
+
+      @context.class_eval { prepend component_module }
+      @context.class_eval { prepend Komponent::Translation }
+
+      @lookup_context.prefixes = ["components/#{component}"]
+
+      capture_block = proc { capture(&block) } if block
+
+      @context.instance_eval do
+        if component_module.respond_to?(:properties)
+          locals = locals.dup
+          component_module.properties.each do |name, options|
+            unless locals.has_key?(name)
+              if options.has_key?(:default)
+                locals[name] = options[:default]
+              elsif options[:required]
+                raise "Missing required component parameter: #{name}"
+              end
+            end
+          end
+        end
+
+        locals.each do |name, value|
+          instance_variable_set(:"@#{name}", locals[name])
+        end
+
+        define_singleton_method(:properties) { locals }
+        define_singleton_method(:block_given_to_component?) { !!block }
+      end
+
+      begin
+        @context.render("components/#{component}/#{parts.join('_')}", &capture_block)
+      rescue ActionView::MissingTemplate
+        warn "[DEPRECATION WARNING] `#{parts.last}` filename in namespace is deprecated in favor of `#{parts.join('_')}`."
+        @context.render("components/#{component}/#{parts.last}", &capture_block)
+      end
+    end
+
+    private
+
+    def resolved_component_path(component)
+      Komponent::ComponentPathResolver.new.resolve(component)
+    end
+  end
+end

lib/komponent/komponent_helper.rb

@@ -2,60 +2,17 @@
 
 module KomponentHelper
   def component(component, locals = {}, &block)
-    component_path = Komponent::ComponentPathResolver.new.resolve(component)
-
-    parts = component.split("/")
-    component_name = parts.join("_")
-    component_path = component_path.join("#{component_name}_component")
-
-    require_dependency(component_path)
-
-    component_module = "#{component_name}_component".camelize.constantize
-    context = controller.view_context.dup
-
-    context.view_flow = view_flow
-
-    view_renderer = context.view_renderer = context.view_renderer.dup
-    lookup_context = view_renderer.lookup_context = view_renderer.lookup_context.dup
-    lookup_context.prefixes = ["components/#{component}"]
-
-    context.class_eval { prepend component_module }
-    context.class_eval { prepend Komponent::Translation }
-
-    capture_block = proc { capture(&block) } if block
-
-    context.instance_eval do
-      if component_module.respond_to?(:properties)
-        locals = locals.dup
-        component_module.properties.each do |name, options|
-          unless locals.has_key?(name)
-            if options.has_key?(:default)
-              locals[name] = options[:default]
-            elsif options[:required]
-              raise "Missing required component parameter: #{name}"
-            end
-          end
-        end
-      end
-
-      locals.each do |name, value|
-        instance_variable_set(:"@#{name}", locals[name])
-      end
-
-      define_singleton_method(:properties) { locals }
-
-      instance_variable_set(:"@block_given_to_component", block)
-    end
-
-    begin
-      context.render("components/#{component}/#{parts.join('_')}", &capture_block)
-    rescue ActionView::MissingTemplate
-      warn "[DEPRECATION WARNING] `#{parts.last}` filename in namespace is deprecated in favor of `#{parts.join('_')}`."
-      context.render("components/#{component}/#{parts.last}", &capture_block)
-    end
+    Komponent::Renderer.new(
+      controller,
+    ).render(
+      component,
+      locals,
+      &block
+    )
   end
   alias :c :component
 
+  # :nocov:
   def render_partial(partial_name, locals = {}, &block)
     warn "[DEPRECATION WARNING] `render_partial` is deprecated. Please use default `render` instead."
 
@@ -79,4 +36,5 @@ def render_partial(partial_name, locals = {}, &block)
 
     rendered_partial
   end
+  # :nocov:
 end

lib/komponent/railtie.rb

@@ -1,9 +1,10 @@
 # frozen_string_literal: true
 
 require 'webpacker'
-require 'komponent/core/component_helper'
-require 'komponent/core/translation'
-require 'komponent/core/component_path_resolver'
+require 'komponent/component_helper'
+require 'komponent/component_path_resolver'
+require 'komponent/component_renderer'
+require 'komponent/translation'
 
 module Komponent
   class Railtie < Rails::Railtie

test/komponent/component_renderer_test.rb

@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class FakeController < ApplicationController
+  def initialize(method_name = nil, &method_body)
+    if method_name and block_given?
+      self.class.send(:define_method, method_name, method_body)
+      Rails.application.routes.draw do
+        get method_name, to: "fake##{method_name}"
+      end
+    end
+  end
+end
+
+class ComponentRendererTest < ActionController::TestCase
+  def test_
+    @controller = FakeController.new
+
+    renderer = Komponent::Renderer.new(@controller)
+    renderer.render('all', text: 'hello world')
+    @context = renderer.context
+
+    assert_respond_to @context, :block_given_to_component?
+    assert_respond_to @context, :properties
+    assert_respond_to @context, :translate
+    assert_equal @context.instance_variable_get(:'@text'), 'hello world'
+  end
+end

test/komponent/komponent_helper_test.rb

@@ -3,13 +3,39 @@
 require 'test_helper'
 
 class KomponentHelperTest < ActionView::TestCase
+  def test_helper_raises_component_missing_error
+    assert_raise Komponent::ComponentPathResolver::MissingComponentError do
+      component('missing')
+    end
+  end
+
   def test_helper_renders_makes_locals_available_as_instance_variables
-    assert_equal %(<div class="world">🌎</div>), component('world', world: "🌎").chomp
+    assert_equal \
+      %(<div class="world">🌎</div>),
+      component('world', world: "🌎").chomp
   end
 
   def test_helper_makes_all_properties_accessible
     assert_equal \
       %(<div class="all">🌎 😎</div>),
       component('all', world: "🌎", sunglasses: "😎").chomp
   end
+
+  def test_helper_renders_localized_keys
+    I18n.locale = :en
+    assert_equal \
+      %(<div class="hello">Hello</div>),
+      component('hello').chomp
+
+    I18n.locale = :fr
+    assert_equal \
+      %(<div class="hello">Bonjour</div>),
+      component('hello').chomp
+  end
+
+  def test_helper_renders_default_property
+    assert_equal \
+      %(<div class="foo">Foobar</div>),
+      component('foo').chomp
+  end
 end

test/test_helper.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require 'simplecov'
+
 ENV['RAILS_ENV'] ||= 'test'
 require File.expand_path('../../fixtures/my_app/config/environment', __FILE__)
 require 'rails/test_help'