Display a hierarchical listing of templates and which other templates they include

view_structure.rb

#! /usr/bin/ruby1.9.1

require 'find'
require 'set'

module Tools
  class ViewStructure
    include Enumerable
    EXTENSIONS = '.erb'

    def initialize(*views_roots)
      @top_level_templates = Set.new
      @inclusions          = Hash.new { |h, path|
        h[path] = []
      }

      @removed_prefix = views_roots.size == 1 ? "#{views_roots.first}/" : ''

      views_roots.each do |root|
        analyze(root)
      end
    end

    def self.show(views_root)
      new(views_root).show
    end

    def self.each(views_root, &block) # :yields: template, level
      new(views_root).each(&block)
    end

    def each(&block) # :yields: template, level
      @top_level_templates.sort_by { |t| t.split('/') }.each do |template|
        walk_inclusions(template, &block)
      end
    end

    def show
      each do |template, level|
        puts "#{'  ' * level}#{template}"
      end
    end


    private

    def analyze(root)
      Find.find root do |path|
        next unless File.file?(path) && EXTENSIONS.include?(File.extname(path))
        File.read(path).scan(%r{
      render
        \s+
        (?::partial\s+=>|partial:)?
        \s*
        (['"])
        (.+?)
        \1      # match closing quote
      }mx) do |_, partial|
          template = unqualified_path(path)
          @top_level_templates << template unless partial?(template)
          resolved = resolve_template(partial, File.dirname(template))
          @inclusions[template] << resolved unless @inclusions[template].include?(resolved)
        end
      end
    end

    def partial?(file)
      File.basename(file).start_with?('_')
    end

    def unqualified_path(path, partial = false)
      parts     = path.sub(%r{^#{@removed_prefix}}, '').split('/')
      fn        = parts[-1].split('.')[0]
      parts[-1] = partial ? "_#{fn}" : fn
      parts.shift if parts[0].empty?
      parts.join('/')
    end

    def resolve_template(template, context)
      resolved = unqualified_path(template, true)
      if !context.empty? && !resolved.include?('/')
        resolved = "#{context}/#{resolved}"
      end
      resolved
    end

    def walk_inclusions(template, level = 0, &block)
      yield template, level
      @inclusions[template].each do |partial|
        walk_inclusions(partial, level + 1, &block)
      end
    end
  end
end

if __FILE__ == $0
  views_root = ARGV[0] || 'app/views'
  if File.directory?(views_root)
    Tools::ViewStructure.show(views_root)
  else
    $stderr.puts "#{views_root} does not appear to be a directory."
  end
end