Merge pull request #35 from shantytown/29-envs-as-ags

Remove all global state, turn Env into a monad.

.rubocop.yml

@@ -5,18 +5,3 @@ LineLength:
 
 Metrics/ModuleLength:
   Max: 150
-
-# This is a stupid lint. Yes, module_function is more explanatory than extend self for most use cases. However, the
-# former does not work if you want the methods to be able to call private methods; the latter does. See
-# https://practicingruby.com/articles/ruby-and-the-singleton-pattern-dont-get-along for a detailed explanation of the
-# problem.
-ModuleFunction:
-  Enabled: False
-
-# FIXME: Only enabling because we are using the singleton pattern still for the
-# Env and TaskEnv classes and they store memoized values that need to be
-# preserved even after mixing in. Without class vars, this does not work. We
-# plan to refactor these singletons out and into class instances that are passed
-# around instead as needed.
-ClassVars:
-  Enabled: False

Shantyconfig

@@ -0,0 +1,5 @@
+require 'shanty/plugins/bundler_plugin'
+require 'shanty/plugins/cucumber_plugin'
+require 'shanty/plugins/rspec_plugin'
+require 'shanty/plugins/rubocop_plugin'
+require 'shanty/plugins/rubygem_plugin'

lib/shanty.rb

@@ -1,30 +1,38 @@
 require 'i18n'
 require 'pathname'
-
 require 'shanty/cli'
 require 'shanty/env'
 require 'shanty/graph'
-
-# Require all plugins and task sets.
-Dir[File.join(__dir__, 'shanty', '{plugins,task_sets}', '*.rb')].each { |f| require f }
+require 'shanty/graph_factory'
 
 module Shanty
   # Main shanty class
   class Shanty
-    include Env
-
     # This is the root directory where the Shanty gem is located. Do not confuse this with the root of the repository
     # in which Shanty is operating, which is available via the TaskEnv class.
     GEM_ROOT = File.expand_path(File.join(__dir__, '..'))
 
+    def initialize
+      @env = Env.new
+    end
+
     def start!
       setup_i18n
-      require!
-      Cli.new(TaskSet.task_sets).run
+      execute_shantyconfig!
+      Cli.new(@env.task_sets, @env, graph).run
     end
 
     private
 
+    def execute_shantyconfig!
+      config_path = File.join(@env.root, Env::CONFIG_FILE)
+      @env.instance_eval(File.read(config_path), config_path)
+    end
+
+    def graph
+      GraphFactory.new(@env).graph
+    end
+
     def setup_i18n
       I18n.enforce_available_locales = true
       I18n.load_path = Dir[File.join(GEM_ROOT, 'translations', '*.yml')]

lib/shanty/cli.rb

@@ -3,8 +3,6 @@
 require 'shanty/info'
 require 'shanty/task_set'
 require 'shanty/env'
-require 'shenanigans/hash/to_ostruct'
-require 'deep_merge'
 
 module Shanty
   # Public: Handle the CLI interface between the user and the registered tasks
@@ -16,8 +14,10 @@ class Cli
 
     CONFIG_FORMAT = '[plugin]:[key] [value]'
 
-    def initialize(task_sets)
+    def initialize(task_sets, env, graph)
       @task_sets = task_sets
+      @env = env
+      @graph = graph
     end
 
     def tasks
@@ -42,7 +42,7 @@ def run
     def global_config
       global_option('-c', '--config [CONFIG]', "Add config via command line in the format #{CONFIG_FORMAT}") do |config|
         if (match = config.match(/(?<plugin>\S+):(?<key>\S+)\s+(?<value>\S+)/))
-          Env.config.merge!(match[:plugin] => { match[:key] => match[:value] })
+          @env.config[match[:plugin].to_sym][match[:key].to_sym] = match[:value]
         else
           fail(I18n.t('cli.invalid_config_param', actual: config, expected: CONFIG_FORMAT))
         end
@@ -73,14 +73,14 @@ def add_options_to_command(task, command)
     def add_action_to_command(name, task, command)
       command.action do |_, options|
         task = tasks[name]
-        options.default(Hash[defaults_for_options(task)])
+        options.default(defaults_for_options(task).to_h)
         enforce_required_options(task, options)
         execute_task(name, task, options)
       end
     end
 
     def execute_task(name, task, options)
-      klass = task[:klass].new
+      klass = task[:klass].new(@env, @graph)
       arity = klass.method(name).arity
       args = (arity >= 1 ? [options] : [])
       klass.send(name, *args)

lib/shanty/env.rb

@@ -1,84 +1,60 @@
 require 'i18n'
 require 'logger'
 require 'pathname'
+require 'shanty/file_tree'
+require 'shanty/plugin'
+require 'shanty/plugins/shantyfile_plugin'
+require 'shanty/task_set'
+require 'shanty/task_sets/basic_task_set'
 require 'yaml'
-require 'shenanigans/hash/to_ostruct'
-
-require 'shanty/config'
-require 'shanty/project_tree'
 
 module Shanty
-  #
-  module Env
-    # Idiom to allow singletons that can be mixed in: http://ozmm.org/posts/singin_singletons.html
-    extend self
-
-    CONFIG_FILE = '.shanty.yml'
+  # RWS Monad pattern.
+  class Env
+    CONFIG_FILE = 'Shantyconfig'
 
-    # This must be defined first due to being a class var that isn't first
-    # first accessed with ||=.
-    @@config = nil
-
-    def clear!
-      @@logger = nil
-      @@environment = nil
-      @@build_number = nil
-      @@root = nil
-      @@config = nil
-      @@project_tree = nil
+    def root
+      @root ||= find_root
     end
 
-    def require!
-      Dir.chdir(root) do
-        (config['require'] || []).each do |path|
-          requires_in_path(path).each { |f| require File.join(root, f) }
-        end
-      end
+    def file_tree
+      @file_tree ||= FileTree.new(root)
     end
 
-    def logger
-      @@logger ||= Logger.new($stdout).tap do |logger|
-        logger.formatter = proc do |_, datetime, _, msg|
-          "#{datetime}: #{msg}\n"
-        end
-      end
+    def plugins
+      @plugins ||= [Plugins::ShantyfilePlugin]
     end
 
-    def environment
-      @@environment ||= ENV['SHANTY_ENV'] || 'local'
+    def task_sets
+      @task_sets ||= [TaskSets::BasicTaskSet]
     end
 
-    def build_number
-      @@build_number ||= (ENV['SHANTY_BUILD_NUMBER'] || 1).to_i
+    def projects
+      @projects ||= {}
     end
 
-    def root
-      @@root ||= find_root
+    def config
+      @config ||= Hash.new { |h, k| h[k] = {} }
     end
 
-    def project_tree
-      @@project_tree ||= ProjectTree.new(root)
-    end
+    def require(*args)
+      new_plugins = []
+      new_task_sets = []
 
-    def config
-      @@config ||= Config.new(root, environment)
-    rescue RuntimeError
-      # Create config object without .shanty.yml if the project root cannot be resolved
-      @@config ||= Config.new(nil, environment)
-    end
+      Plugin.send(:define_singleton_method, :inherited) { |klass| new_plugins << klass }
+      TaskSet.send(:define_singleton_method, :inherited) { |klass| new_task_sets << klass }
 
-    private
+      super(*args)
 
-    def requires_in_path(path)
-      if File.directory?(path)
-        Dir[File.join(path, '**', '*.rb')]
-      elsif File.exist?(path)
-        [path]
-      else
-        Dir[path]
-      end
+      Plugin.singleton_class.send(:remove_method, :inherited)
+      TaskSet.singleton_class.send(:remove_method, :inherited)
+
+      plugins.concat(new_plugins)
+      task_sets.concat(new_task_sets)
     end
 
+    private
+
     def find_root
       fail I18n.t('missing_root', config_file: CONFIG_FILE) if root_dir.nil?
       root_dir

lib/shanty/project_tree.rb → lib/shanty/file_tree.rb

@@ -5,7 +5,7 @@ module Shanty
   #
   # FIXME: The ignores are not implemented yet, this work has been recorded in
   # issue #9 (https://github.com/shantytown/shanty/issues/9).
-  class ProjectTree
+  class FileTree
     # Allow double globbing, and matching hidden files.
     GLOB_FLAGS = File::FNM_EXTGLOB | File::FNM_DOTMATCH
     # FIXME: Basic ignores until the .gitignore file can be loaded instead.

lib/shanty/project_sorter.rb → lib/shanty/graph_factory.rb

@@ -6,39 +6,45 @@
 
 module Shanty
   # Public: Sorts projects using Tarjan's strongly connected components algorithm.
-  class ProjectSorter
+  class GraphFactory
     include TSort
 
     # Public: Initialise a ProjectLinker.
     #
-    # projects - An array of projects to use. These will be mutated and sorted when the linking takes place.
-    def initialize(projects)
-      @projects = projects
+    # env - ...
+    def initialize(env)
+      @env = env
     end
 
     # Private: Given a list of projects, sort them and construct a graph.
     #
     # The sorting uses Tarjan's strongly connected components algorithm.
     #
     # Returns a Graph with the projects sorted.
-    def sort
+    def graph
       Graph.new(project_path_trie, tsort)
     end
 
     private
 
+    def project_path_trie
+      @project_path_trie ||= Containers::Trie.new.tap do |trie|
+        projects.map { |project| trie[project.path] = project }
+      end
+    end
+
+    def projects
+      @projects ||= @env.plugins.each_with_object(Set.new) do |plugin, s|
+        s.merge(plugin.projects(@env))
+      end
+    end
+
     def tsort_each_node
-      @projects.each { |p| yield p }
+      projects.each { |p| yield p }
     end
 
     def tsort_each_child(project)
       project_path_trie.get(project.path).parents.each { |p| yield p }
     end
-
-    def project_path_trie
-      @project_path_trie ||= Containers::Trie.new.tap do |trie|
-        @projects.map { |project| trie[project.path] = project }
-      end
-    end
   end
 end

lib/shanty/logger.rb

@@ -0,0 +1,15 @@
+module Shanty
+  # Small mixin that gives the receiver class a logger method. This method simply wraps the Ruby Logger class with a
+  # nice consistent logging format.
+  module Logger
+    module_function
+
+    def logger
+      @logger ||= ::Logger.new($stdout).tap do |logger|
+        logger.formatter = proc do |_, datetime, _, msg|
+          "#{datetime}: #{msg}\n"
+        end
+      end
+    end
+  end
+end