Add CI workflow job to print importer help info

.github/workflows/ci.yml

@@ -52,3 +52,23 @@ jobs:
           bundler-cache: true
       - name: Run RuboCop
         run:  bash script/fmt
+
+  cli_help_info_visualization:
+    name: "CLI Help Info Visualization"
+    runs-on: "ubuntu-latest"
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby_version:
+          - 2.7
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 5
+      - name: "Set up Ruby ${{ matrix.ruby_version }}"
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby_version }}
+          bundler-cache: true
+      - name: Print Importer Help Menus
+        run:  bundle exec ruby script/cli_help_visualizer.rb

script/cli_help_visualizer.rb

@@ -0,0 +1,38 @@
+require "bundler/setup"
+require "jekyll-import"
+require "mercenary"
+
+# The out-of-box Help output contains noise from * injected default options* such as
+# `--help`, `--verbose`, etc in addition to options injected options from the `jekyll`
+# executable.
+# Therefore create a custom `Mercenary::Command` instances along with some monkey-patches
+# to prettify output.
+
+module Mercenary
+  class Option
+    def to_s(justify_length=15)
+      "#{short.to_s.rjust(10)} #{long.ljust(justify_length)}  #{description}"
+    end
+  end
+
+  class Presenter
+    def command_options_presentation
+      c_opts = command.options
+      return nil if c_opts.empty?
+
+      justify_length = c_opts.map { |o| o.long.length }.max
+      c_opts.map { |o| o.to_s(justify_length) }.join("\n")
+    end
+  end
+end
+
+prog = Mercenary::Program.new(:jekyll).command(:import, &:itself)
+
+JekyllImport::Importer.subclasses.each do |importer|
+  puts "\n\n"
+  name = importer.to_s.split("::").last.downcase
+  cmd  = Mercenary::Command.new(name, prog)
+  cmd.syntax "#{name} [options]"
+  importer.specify_options(cmd)
+  puts cmd
+end