WIP: add Niente, a 'do nothing' display service

lacci/lib/scarpe/niente.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+# Niente -- Italian for "nothing" -- is a null display service
+# that doesn't display anything. It does very little, while
+# keeping a certain amount of "mental model" or schema of
+# how a real display service should act.
+module Niente; end
+
+require_relative "niente/logger"
+Shoes::Log.instance = Niente::LogImpl.new
+
+require_relative "niente/drawable"
+require_relative "niente/app"
+require_relative "niente/display_service"
+
+if ENV["SHOES_SPEC_TEST"]
+  require_relative "niente/shoes_spec"
+  Shoes::Spec.instance = Niente::Test
+end
+
+Shoes::DisplayService.set_display_service_class(Niente::DisplayService)
+

lacci/lib/scarpe/niente/app.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Niente
+  class App < Drawable
+    def initialize(properties)
+      super
+
+      bind_shoes_event(event_name: "init") { init }
+      bind_shoes_event(event_name: "run") { run }
+      bind_shoes_event(event_name: "destroy") { destroy }
+    end
+
+    def init
+    end
+
+    def run
+      send_shoes_event("wait", event_name: "custom_event_loop")
+    end
+
+    def destroy
+    end
+  end
+end

lacci/lib/scarpe/niente/display_service.rb

@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+module Niente
+  # This is a "null" DisplayService, doing as little as it
+  # can get away with.
+  class DisplayService < Shoes::DisplayService
+    include Shoes::Log
+
+    class << self
+      attr_accessor :instance
+    end
+
+    def initialize
+      if Niente::DisplayService.instance
+        raise Scarpe::SingletonError, "ERROR! This is meant to be a singleton!"
+      end
+
+      Niente::DisplayService.instance = self
+
+      log_init("Niente::DisplayService")
+      super()
+    end
+
+    # Create a fake display drawable for a specific Shoes drawable, and pair it with
+    # the linkable ID for this Shoes drawable.
+    #
+    # @param drawable_class_name [String] The class name of the Shoes drawable, e.g. Shoes::Button
+    # @param drawable_id [String] the linkable ID for drawable events
+    # @param properties [Hash] a JSON-serialisable Hash with the drawable's Shoes styles
+    # @param is_widget [Boolean] whether the class is a user-defined Shoes::Widget subclass
+    # @return [Webview::Drawable] the newly-created Webview drawable
+    def create_display_drawable_for(drawable_class_name, drawable_id, properties, is_widget:)
+      existing = query_display_drawable_for(drawable_id, nil_ok: true)
+      if existing
+        @log.warn("There is already a display drawable for #{drawable_id.inspect}! Returning #{existing.class.name}.")
+        return existing
+      end
+
+      if drawable_class_name == "App"
+        @app = Niente::App.new(properties)
+        set_drawable_pairing(drawable_id, @app)
+
+        return @app
+      end
+
+      display_drawable = Niente::Drawable.new(properties)
+      set_drawable_pairing(drawable_id, display_drawable)
+
+      return display_drawable
+    end
+
+    # Destroy the display service and the app. Quit the process (eventually.)
+    #
+    # @return [void]
+    def destroy
+      @app.destroy
+      DisplayService.instance = nil
+    end
+  end
+end
+

lacci/lib/scarpe/niente/drawable.rb

@@ -0,0 +1,55 @@
+module Niente
+  class Drawable < Shoes::Linkable
+    attr_reader :shoes_linkable_id
+    attr_reader :parent
+    attr_reader :children
+
+    def initialize(props)
+      @shoes_linkable_id = props.delete("shoes_linkable_id") || props.delete(:shoes_linkable_id)
+      @data = props
+
+      super(linkable_id: @shoes_linkable_id)
+
+      bind_shoes_event(event_name: "parent", target: shoes_linkable_id) do |new_parent_id|
+        display_parent = DisplayService.instance.query_display_drawable_for(new_parent_id)
+        if @parent != display_parent
+          set_parent(display_parent)
+        end
+      end
+
+      # When Shoes drawables change properties, we get a change notification here
+      bind_shoes_event(event_name: "prop_change", target: shoes_linkable_id) do |prop_changes|
+        prop_changes.each do |k, v|
+          instance_variable_set("@" + k, v)
+        end
+        properties_changed(prop_changes) if respond_to?(:properties_changed)
+      end
+
+      bind_shoes_event(event_name: "destroy", target: shoes_linkable_id) do
+      end
+    end
+
+    def set_parent(new_parent)
+      @parent&.remove_child(self)
+      new_parent&.add_child(self)
+      @parent = new_parent
+    end
+
+    # Do not call directly, use set_parent
+    def remove_child(child)
+      @children ||= []
+      unless @children.include?(child)
+        STDERR.puts("remove_child: no such child(#{child.inspect}) for"\
+          " parent(#{parent.inspect})!")
+      end
+      @children.delete(child)
+    end
+
+    # Do not call directly, use set_parent
+    def add_child(child)
+      @children ||= []
+      @children << child
+    end
+  end
+end
+

lacci/lib/scarpe/niente/logger.rb

@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require "shoes/log"
+require "json"
+
+module Niente; end
+class Niente::LogImpl
+  include Shoes::Log # for constants
+
+  class PrintLogger
+    def initialize(_)
+    end
+
+    [:error, :warn, :debug, :info].each do |level|
+      define_method(level) do |msg|
+        puts "#{level}: #{msg}"
+      end
+    end
+  end
+
+  def logger_for_component(component)
+    PrintLogger.new(component.to_s)
+  end
+
+  def configure_logger(log_config)
+  end
+end
+
+#Shoes::Log.instance = Niente::LogImpl.new

lacci/lib/scarpe/niente/shoes_spec.rb

@@ -0,0 +1,92 @@
+# frozen_string_literal: true
+
+require "minitest"
+require "scarpe/components/string_helpers"
+
+module Niente; end
+
+class Niente::Test
+  def self.run_shoes_spec_test_code(code, class_name: nil, test_name: nil)
+    if @shoes_spec_init
+      raise MultipleShoesSpecRunsError, "Scarpe-Webview can only run a single Shoes spec per process!"
+    end
+    @shoes_spec_init = true
+
+    require "scarpe/components/minitest_export_reporter"
+    Minitest::Reporters::ShoesExportReporter.activate!
+
+    class_name ||= ENV["SHOES_MINITEST_CLASS_NAME"] || "TestShoesSpecCode"
+    test_name ||= ENV["SHOES_MINITEST_METHOD_NAME"] || "test_shoes_spec"
+
+    Shoes::DisplayService.subscribe_to_event("heartbeat", nil) do
+      unless @hb_init
+        Minitest.run []
+        Shoes::App.instance.destroy
+      end
+      @hb_init = true
+    end
+
+    test_class = Class.new(Niente::ShoesSpecTest)
+    Object.const_set(Scarpe::Components::StringHelpers.camelize(class_name), test_class)
+    test_name = "test_" + test_name unless test_name.start_with?("test_")
+    test_class.define_method(test_name) do
+      STDERR.puts "Started running #{class_name.inspect}::#{test_name.inspect}"
+      eval(code)
+    end
+  end
+end
+
+class Niente::ShoesSpecTest < Minitest::Test
+  Shoes::Drawable.drawable_classes.each do |drawable_class|
+    finder_name = drawable_class.dsl_name
+
+    define_method(finder_name) do |*args|
+      app = Shoes::App.instance
+
+      drawables = app.find_drawables_by(drawable_class, *args)
+      raise Scarpe::MultipleDrawablesFoundError, "Found more than one #{finder_name} matching #{args.inspect}!" if drawables.size > 1
+      raise Scarpe::NoDrawablesFoundError, "Found no #{finder_name} matching #{args.inspect}!" if drawables.empty?
+
+      Niente::ShoesSpecProxy.new(drawables[0])
+    end
+  end
+end
+
+class Niente::ShoesSpecProxy
+  attr_reader :obj
+  attr_reader :linkable_id
+  attr_reader :display
+
+  JS_EVENTS = [:click, :hover, :leave, :change]
+
+  def initialize(obj)
+    @obj = obj
+    @linkable_id = obj.linkable_id
+    @display = ::Shoes::DisplayService.display_service.query_display_drawable_for(obj.linkable_id)
+  end
+
+  def method_missing(method, ...)
+    if @obj.respond_to?(method)
+      self.singleton_class.define_method(method) do |*args, **kwargs, &block|
+        @obj.send(method, *args, **kwargs, &block)
+      end
+      send(method, ...)
+    else
+      super # raise an exception
+    end
+  end
+
+  def trigger(event_name, *args)
+    # TODO
+  end
+
+  JS_EVENTS.each do |ev|
+    define_method "trigger_#{ev}" do |*args|
+      trigger(ev, *args)
+    end
+  end
+
+  def respond_to_missing?(method_name, include_private = false)
+    @obj.respond_to_missing?(method_name, include_private)
+  end
+end

lacci/lib/shoes/app.rb

@@ -168,7 +168,9 @@ def run
       case @event_loop_type
       when "wait"
         # Display lib wants us to busy-wait instead of it.
-        sleep 0.1 until @do_shutdown
+        until @do_shutdown
+          Shoes::DisplayService.dispatch_event("heartbeat", nil)
+        end
       when "displaylib"
         # If run event returned, that means we're done.
         destroy