Introduce `bin/git-read` command line interface

This commit introduces the bin/git-read executable. So far, the executable can be passed three flags.

To view the possible options, execute with the --help flag to output its usage documentation:

usage: git read [--help] [-v|--verbose] [-g|--git-dir <path>] [-o|--output-dir <path>]

Generate HTML from your project's Git history

OPTIONS
      --output-dir
          specify the directory where the site will be built

      --git-dir
          specify the parent directory of the project's .git/ directory

The end result of a successful bin/get-read execution is that middleman build output will be written to the directory passed as the --output-dir flag.

Test coverage

To ensure that the output of the bin/git-read command is the same as what’s covered in other System Test cases declared in test/system, extract the #with_built_output helper.

The #with_built_output leverages the test harness’ test-isolated temporary directory, and invokes bin/git-read to read from and write to a build/ directory within the tmpdir. The contents of the build/ directory are served by a constructed through a Rack::Static middleware Rack::Builder domain specific language.

To ensure that executions of bin/git-read exit with a 0 status code, this commit introduces the first test case outside of the test/system directory.

Since that test case doesn’t require all of the System Test case setup, the test/test_helper.rb file serves as a re-usable chunk, shared by both styles of test.

bin/git-read

diff --git a/bin/git-read b/bin/git-read
new file mode 100755
index 0000000..a9033d6
--- /dev/null
+++ b/bin/git-read
@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+
+set -e
+
+ARGS=( "$@" )
+
+VERBOSE="--no-verbose"
+
+for i in "${!ARGS[@]}"; do
+  case "${ARGS[i]}" in
+    "")
+      continue
+      ;;
+    -o|--output-dir|--build-dir)
+      OUTPUT_DIR="${ARGS[i+1]}"
+      unset 'ARGS[i+1]'
+      ;;
+    -g|--git-dir)
+      GIT_DIR="${ARGS[i+1]}"
+      unset 'ARGS[i+1]'
+      ;;
+    -v|--verbose)
+      VERBOSE="--verbose"
+      ;;
+    -h|--help)
+      cat <<-HELP
+usage: git read [--help] [-v|--verbose] [-g|--git-dir <path>] [-o|--output-dir <path>]
+
+Generate HTML from your project's Git history
+
+OPTIONS
+
+      --output-dir
+          specify the directory where the site will be built
+
+      --git-dir
+          specify the parent directory of the project's .git/ directory
+
+      --verbose
+          print debugging information during the build process
+HELP
+      exit 0
+      ;;
+    *)
+      continue
+      ;;
+  esac
+  unset 'ARGS[i]'
+done
+
+build_site() {
+  git_dir="${1}"
+  output_dir="${2}"
+  verbosity="${@}"
+  tool_dir="$(dirname "${BASH_SOURCE[0]}")/../"
+
+  export GIT_DIR=$git_dir
+
+  mkdir -p $output_dir
+  cd $tool_dir
+  bundle exec middleman build --build-dir=$output_dir $verbosity
+  cd $git_dir
+}
+
+build_site \
+  $(realpath ${GIT_DIR-./}) \
+  $(realpath ${OUTPUT_DIR-./build/}) \
+  "${VERBOSE}"

test/application_system_test_case.rb

diff --git a/test/application_system_test_case.rb b/test/application_system_test_case.rb
index d22027e..c73caa8 100644
--- a/test/application_system_test_case.rb
+++ b/test/application_system_test_case.rb
@@ -1,17 +1,8 @@
-require "bundler"
-
-Bundler.require(:default, :test)
-
-ENV["MODE"] ||= "build"
-
-require "minitest/autorun"
+require "test_helper"
 require "middleman/rack"
-require "active_support"
-require "active_support/test_case"
 require "pathname"
 require "tmpdir"
 
-
 require_relative "../helpers/url_helpers"
 
 class ApplicationSystemTestCase < ActiveSupport::TestCase
@@ -43,6 +34,29 @@ class ApplicationSystemTestCase < ActiveSupport::TestCase
     @repository.commit(message)
   end
 
+  def with_built_output(&block)
+    git_directory = Pathname(@repository.dir.path)
+    build_directory = git_directory.join("build")
+
+    system <<~BASH, exception: true
+      bin/git-read \
+        --verbose \
+        --git-dir #{git_directory} \
+        --output-dir #{build_directory}
+    BASH
+
+    Capybara.app = Rack::Builder.new do
+      use Rack::Static,
+        urls: [""],
+        root: build_directory,
+        index: "index.html"
+
+      run -> (*) {}
+    end
+
+    block.call
+  end
+
   def with_git_repository(&block)
     ClimateControl.modify(GIT_DIR: @repository.dir.path) do
       Capybara.app = Middleman.server

test/bin/git_read_test.rb

diff --git a/test/bin/git_read_test.rb b/test/bin/git_read_test.rb
new file mode 100644
index 0000000..b9f563e
--- /dev/null
+++ b/test/bin/git_read_test.rb
@@ -0,0 +1,9 @@
+require "test_helper"
+
+class GitReadTest < ActiveSupport::TestCase
+  test "bin/git-read --help exits with a 0 status" do
+    system("bin/git-read --help", exception: true)
+
+    assert_equal(0, $?)
+  end
+end

test/system/visitor_views_built_site_test.rb

diff --git a/test/system/visitor_views_built_site_test.rb b/test/system/visitor_views_built_site_test.rb
new file mode 100644
index 0000000..49c6038
--- /dev/null
+++ b/test/system/visitor_views_built_site_test.rb
@@ -0,0 +1,16 @@
+require "application_system_test_case"
+
+class VisitorViewsBuiltSiteTest < ApplicationSystemTestCase
+  test "visitor views built site" do
+    stage_file("README.md", "Ignore me")
+    commit("From the command line")
+
+    with_built_output do
+      visit root_path
+      expand_history
+      click_on "From the command line"
+
+      assert_selector "h1", text: "From the command line"
+    end
+  end
+end

test/test_helper.rb

diff --git a/test/test_helper.rb b/test/test_helper.rb
new file mode 100644
index 0000000..22de50b
--- /dev/null
+++ b/test/test_helper.rb
@@ -0,0 +1,9 @@
+require "bundler"
+
+Bundler.require(:default, :test)
+
+ENV["MODE"] ||= "build"
+
+require "minitest/autorun"
+require "active_support"
+require "active_support/test_case"

Introduce bin/git-read command line interface

Test coverage

Introduce `bin/git-read` command line interface