Use a single Scarpe::App instance as self nearly everywhere

examples/selfitude.rb

@@ -0,0 +1,18 @@
+def printish(msg)
+  #$stderr.puts msg
+  File.open("/tmp/shoesy_stuff.txt", "a") do |f|
+    f.write(msg + "\n")
+  end
+end
+
+Shoes.app do
+  printish "Self top: #{self.inspect}" # It's an instance of Shoes::App, yes
+  stack do
+    printish "Self in stack: #{self.inspect}" # Yup, here too
+  end
+  button("Clickity") do
+    alert("You clicked me!")
+    printish "Self in button handler: #{self.inspect}" # And here too
+  end
+end
+

lib/scarpe/app.rb

@@ -20,22 +20,24 @@ def initialize(
       debug: ENV["SCARPE_DEBUG"] ? true : false,
       &app_code_body
     )
-      log_init("Scarpe::App")
-
       if Scarpe::App.instance
         @log.error("Trying to create a second Scarpe::App in the same process! Fail!")
         raise "Cannot create multiple Scarpe::App objects!"
       else
         Scarpe::App.instance = self
       end
 
+      log_init("Scarpe::App")
+
       @do_shutdown = false
 
       super
 
       # This creates the DocumentRoot, including its corresponding display widget
       @document_root = Scarpe::DocumentRoot.new
 
+      @slots = []
+
       # Now create the App display widget
       create_display_widget
 
@@ -68,7 +70,31 @@ def init
       send_shoes_event(event_name: "init")
       return if @do_shutdown
 
-      @document_root.instance_eval(&@app_code_body)
+      ::Scarpe::App.instance.with_slot(@document_root, &@app_code_body)
+    end
+
+    # "Container" widgets like flows, stacks, masks and the document root
+    # are considered "slots" in Scarpe parlance. When a new slot is created,
+    # we push it here in order to track what widgets are found in that slot.
+    def push_slot(slot)
+      @slots.push(slot)
+    end
+
+    def pop_slot
+      @slots.pop
+    end
+
+    def current_slot
+      @slots[-1]
+    end
+
+    def with_slot(slot_item, &block)
+      return unless block_given?
+
+      push_slot(slot_item)
+      Scarpe::App.instance.instance_eval(&block)
+    ensure
+      pop_slot
     end
 
     # This isn't supposed to return. The display service should take control
@@ -85,5 +111,63 @@ def destroy(send_event: true)
       @do_shutdown = true
       send_shoes_event(event_name: "destroy") if send_event
     end
+
+    def all_widgets
+      out = []
+
+      to_add = @document_root.children
+      until to_add.empty?
+        out.concat(to_add)
+        to_add = to_add.flat_map(&:children).compact
+      end
+
+      out
+    end
+
+    # We can add various ways to find widgets here.
+    # These are sort of like Shoes selectors, used for testing.
+    def find_widgets_by(*specs)
+      widgets = all_widgets
+      specs.each do |spec|
+        if spec.is_a?(Class)
+          widgets.select! { |w| spec === w }
+        elsif spec.is_a?(Symbol)
+          s = spec.to_s
+          case s[0]
+          when "$"
+            begin
+              # I'm not finding a global_variable_get or similar...
+              global_value = eval s
+              widgets &= [global_value]
+            rescue
+              raise "Error getting global variable: #{spec.inspect}"
+            end
+          when "@"
+            if app.instance_variables.include?(spec)
+              widgets &= [self.instance_variable_get(spec)]
+            else
+              raise "Can't find top-level instance variable: #{spec.inspect}!"
+            end
+          else
+          end
+        else
+          raise("Don't know how to find widgets by #{spec.inspect}!")
+        end
+      end
+      widgets
+    end
+  end
+end
+
+# DSL methods
+class Scarpe::App
+  def background(...)
+    current_slot.background(...)
   end
+
+  def border(...)
+    current_slot.border(...)
+  end
+
+  alias_method :info, :puts
 end

lib/scarpe/cats_cradle.rb

@@ -166,9 +166,9 @@ def on_event(event, &block)
     # Also, wait, what's up with span? What *is* that?
     WIDGET_FINDERS.each do |finder_name, scarpe_class|
       define_method(finder_name) do |*args|
-        root = Scarpe::App.instance.document_root
+        app = Scarpe::App.instance
 
-        widgets = root.find_widgets_by(scarpe_class, *args)
+        widgets = app.find_widgets_by(scarpe_class, *args)
         raise "Found more than one #{finder_name} matching #{args.inspect}!" if widgets.size > 1
         raise "Found no #{finder_name} matching #{args.inspect}!" if widgets.empty?
 

lib/scarpe/document_root.rb

@@ -1,66 +1,16 @@
 # frozen_string_literal: true
 
 class Scarpe
-  class DocumentRoot < Scarpe::Widget
-    include Scarpe::Background
-
+  class DocumentRoot < Scarpe::Slot
     def initialize
       super
 
       create_display_widget
     end
 
-    # This can be absolutely huge in console output, and it's frequently printed.
+    # The default inspect string can be absolutely huge in console output, and it's frequently printed.
     def inspect
       "<Scarpe::DocumentRoot>"
     end
-
-    alias_method :info, :puts
-
-    def all_widgets
-      out = []
-
-      to_add = self.children
-      until to_add.empty?
-        out.concat(to_add)
-        to_add = to_add.flat_map(&:children).compact
-      end
-
-      out
-    end
-
-    # We can add various ways to find widgets here.
-    # These are sort of like Shoes selectors, used for testing.
-    def find_widgets_by(*specs)
-      widgets = all_widgets
-      app = Scarpe::App.instance
-      specs.each do |spec|
-        if spec.is_a?(Class)
-          widgets.select! { |w| spec === w }
-        elsif spec.is_a?(Symbol)
-          s = spec.to_s
-          case s[0]
-          when "$"
-            begin
-              # I'm not finding a global_variable_get or similar...
-              global_value = eval s
-              widgets = [global_value]
-            rescue
-              raise "Error getting global variable: #{spec.inspect}"
-            end
-          when "@"
-            if app.instance_variables.include?(spec)
-              widgets = [app.instance_variable_get(spec)]
-            else
-              raise "Can't find top-level instance variable: #{spec.inspect}!"
-            end
-          else
-          end
-        else
-          raise("Don't know how to find widgets by #{spec.inspect}!")
-        end
-      end
-      widgets
-    end
   end
 end

lib/scarpe/download.rb

@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require "net/http"
+require "openssl"
+require "nokogiri"
+
+class Scarpe::Widget
+  def download(url)
+    Thread.new do
+      begin
+        uri = URI(url)
+        http = Net::HTTP.new(uri.host, uri.port)
+        http.use_ssl = true
+        http.verify_mode = OpenSSL::SSL::VERIFY_NONE
+
+        request = Net::HTTP::Get.new(uri.request_uri)
+
+        http.request(request) do |response|
+          case response
+          when Net::HTTPSuccess
+            # content = response.body
+
+            # headers = response.header
+
+            html_get_title(content)
+          else
+            Scarpe.error("Failed to download content. Response code: #{response.code}")
+          end
+        end
+      rescue StandardError => e
+        Scarpe.error("Error occurred while downloading: #{e.message}")
+      end
+    end
+  end
+
+  private
+
+  def html_get_title(content)
+    doc = Nokogiri::HTML(content)
+
+    title = doc.at_css("title")&.text&.strip || ""
+
+    # headings = doc.css("h1").map(&:text)
+
+    title
+  end
+end

lib/scarpe/flow.rb

@@ -1,10 +1,7 @@
 # frozen_string_literal: true
 
 class Scarpe
-  class Flow < Scarpe::Widget
-    include Scarpe::Background
-    include Scarpe::Border
-
+  class Flow < Scarpe::Slot
     display_properties :width, :height, :margin, :padding
 
     def initialize(width: nil, height: "100%", margin: nil, padding: nil, &block)
@@ -13,7 +10,7 @@ def initialize(width: nil, height: "100%", margin: nil, padding: nil, &block)
       # Create the display-side widget *before* instance_eval, which will add child widgets with their display widgets
       create_display_widget
 
-      instance_eval(&block)
+      Scarpe::App.instance.with_slot(self, &block) if block_given?
     end
   end
 end

lib/scarpe/shape.rb

@@ -13,6 +13,7 @@ def initialize(left: nil, top: nil, path_commands: nil, &block)
 
       super()
       create_display_widget
+
       instance_eval(&block) if block_given?
     end
   end

lib/scarpe/slot.rb

@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+class Scarpe::Slot < Scarpe::Widget
+  include Scarpe::Background
+  include Scarpe::Border
+end

lib/scarpe/stack.rb

@@ -1,13 +1,7 @@
 # frozen_string_literal: true
 
-require "net/http"
-require "openssl"
-require "nokogiri"
-
 class Scarpe
-  class Stack < Scarpe::Widget
-    include Scarpe::Background
-    include Scarpe::Border
+  class Stack < Scarpe::Slot
     include Scarpe::Spacing
 
     display_properties :width, :height, :margin, :padding, :scroll, :margin_top, :margin_left, :margin_right, :margin_bottom, :options
@@ -21,50 +15,8 @@ def initialize(width: nil, height: "100%", margin: nil, padding: nil, scroll: fa
       super
 
       create_display_widget
-      # Create the display-side widget *before* instance_eval, which will add child widgets with their display widgets
-      instance_eval(&block) if block_given?
-    end
-  end
-
-  class Widget
-    def download(url)
-      Thread.new do
-        begin
-          uri = URI(url)
-          http = Net::HTTP.new(uri.host, uri.port)
-          http.use_ssl = true
-          http.verify_mode = OpenSSL::SSL::VERIFY_NONE
-
-          request = Net::HTTP::Get.new(uri.request_uri)
-
-          http.request(request) do |response|
-            case response
-            when Net::HTTPSuccess
-              # content = response.body
-
-              # headers = response.header
-
-              get_title(content)
-            else
-              Scarpe.error("Failed to download content. Response code: #{response.code}")
-            end
-          end
-        rescue StandardError => e
-          Scarpe.error("Error occurred while downloading: #{e.message}")
-        end
-      end
-    end
-
-    private
-
-    def get_title(content)
-      doc = Nokogiri::HTML(content)
-
-      title = doc.at_css("title")&.text&.strip || ""
-
-      # headings = doc.css("h1").map(&:text)
-
-      title
+      # Create the display-side widget *before* running the block, which will add child widgets with their display widgets
+      Scarpe::App.instance.with_slot(self, &block) if block_given?
     end
   end
 end