Exercise the application through a System Test

System Testing

This commit adds a foundation for a test harness inspired by Rails’ System Tests.

System tests are the highest level tests available to a web application, and serve as a proxy for the end-user experience.

To drive the application, integrate with Capybara’s Rack mounting capabilities by mounting Middleman as a Rack application.

Dependencies

Utilize Bundler to add a test group dependency on Capybara to visit the application from the test suite through its domain specific language-style navigation helpers methods.

Extend Minitest’s provided assertions with Capybara-specified assertions.

It is important to require "minitest/autorun" explicitly, so that a Test Case executes all of the tests it declares, when executed from the comfort of our command line.

To run the suite, execute:

ruby -I test test/system/visitor_views_readme_test.rb

Gemfile

diff --git a/Gemfile b/Gemfile
index 195f938..5e5fb63 100644
--- a/Gemfile
+++ b/Gemfile
@@ -3,3 +3,7 @@ source 'https://rubygems.org'
 gem 'middleman', '~> 4.2'
 gem 'tzinfo-data', platforms: [:mswin, :mingw, :jruby, :x64_mingw]
 gem 'wdm', '~> 0.1', platforms: [:mswin, :mingw, :x64_mingw]
+
+group :test do
+  gem 'capybara', require: 'capybara/minitest'
+end

Gemfile.lock

diff --git a/Gemfile.lock b/Gemfile.lock
index 4b112a8..8707399 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -9,6 +9,14 @@ GEM
     addressable (2.7.0)
       public_suffix (>= 2.0.2, < 5.0)
     backports (3.17.0)
+    capybara (3.31.0)
+      addressable
+      mini_mime (>= 0.1.3)
+      nokogiri (~> 1.8)
+      rack (>= 1.6.0)
+      rack-test (>= 0.6.3)
+      regexp_parser (~> 1.5)
+      xpath (~> 3.2)
     coffee-script (2.4.1)
       coffee-script-source
       execjs
@@ -68,7 +76,16 @@ GEM
       servolux
       tilt (~> 2.0.9)
       uglifier (~> 3.0)
+    mini_mime (1.0.2)
+    mini_portile2 (2.4.0)
     minitest (5.14.0)
+    nokogiri (1.10.9)
+      mini_portile2 (~> 2.4.0)
+    nokogiri (1.10.9-java)
+    nokogiri (1.10.9-x64-mingw32)
+      mini_portile2 (~> 2.4.0)
+    nokogiri (1.10.9-x86-mingw32)
+      mini_portile2 (~> 2.4.0)
     padrino-helpers (0.13.3.4)
       i18n (~> 0.6, >= 0.6.7)
       padrino-support (= 0.13.3.4)
@@ -78,9 +95,12 @@ GEM
     parallel (1.19.1)
     public_suffix (4.0.3)
     rack (2.2.2)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
     rb-fsevent (0.10.3)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
+    regexp_parser (1.7.0)
     sassc (2.2.1)
       ffi (~> 1.9)
     sassc (2.2.1-x64-mingw32)
@@ -100,6 +120,8 @@ GEM
     uglifier (3.2.0)
       execjs (>= 0.3.0, < 3)
     wdm (0.1.1)
+    xpath (3.2.0)
+      nokogiri (~> 1.8)
 
 PLATFORMS
   java
@@ -109,6 +131,7 @@ PLATFORMS
   x86-mswin32
 
 DEPENDENCIES
+  capybara
   middleman (~> 4.2)
   tzinfo-data
   wdm (~> 0.1)

config.rb

diff --git a/config.rb b/config.rb
index 12bce69..fc05d70 100644
--- a/config.rb
+++ b/config.rb
@@ -1,6 +1,8 @@
 # Activate and configure extensions
 # https://middlemanapp.com/advanced/configuration/#configuring-extensions
 
+config[:mode] = (ENV.fetch("MODE") { build? ? "build" : "server" }).to_sym
+
 activate :external_pipeline,
          name: :webpack,
          command: build? ?  "yarn build" : "yarn start",

test/system/visitor_views_readme_test.rb

diff --git a/test/system/visitor_views_readme_test.rb b/test/system/visitor_views_readme_test.rb
new file mode 100644
index 0000000..3d473e5
--- /dev/null
+++ b/test/system/visitor_views_readme_test.rb
@@ -0,0 +1,28 @@
+require "bundler"
+
+Bundler.require(:default, :test)
+
+ENV["MODE"] ||= "build"
+
+require "minitest/autorun"
+require "middleman/rack"
+require "active_support"
+require "active_support/test_case"
+
+Capybara.app = Middleman.server
+
+class VisitorViewsReadmeTest < ActiveSupport::TestCase
+  include Capybara::DSL
+  include Capybara::Minitest::Assertions
+
+  teardown do
+    Capybara.reset_sessions!
+    Capybara.use_default_driver
+  end
+
+  test "visitor views README" do
+    visit "/index.html"
+
+    assert_text "git-read"
+  end
+end