V2 base class

Signed-off-by: Jordan Hollinger <[email protected]>

lib/blueprinter.rb

@@ -5,4 +5,5 @@ module Blueprinter
   autoload :BlueprinterError, 'blueprinter/blueprinter_error'
   autoload :Errors, 'blueprinter/errors'
   autoload :Extension, 'blueprinter/extension'
+  autoload :V2, 'blueprinter/v2'
 end

lib/blueprinter/errors.rb

@@ -3,5 +3,6 @@
 module Blueprinter
   module Errors
     autoload :InvalidBlueprint, 'blueprinter/errors/invalid_blueprint'
+    autoload :UnknownView, 'blueprinter/errors/unknown_view'
   end
 end

lib/blueprinter/errors/unknown_view.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+module Blueprinter
+  module Errors
+    class UnknownView < Blueprinter::BlueprinterError; end
+  end
+end

lib/blueprinter/v2.rb

@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+module Blueprinter
+  class V2
+    class << self
+      attr_accessor :views, :fields, :extensions, :blueprint_name
+    end
+
+    self.views = {}
+    self.fields = {}
+    self.extensions = []
+    self.blueprint_name = []
+
+    # Initialize subclass
+    def self.inherited(subclass)
+      subclass.views = {}
+      subclass.fields = fields.dup
+      subclass.extensions = extensions.dup
+      subclass.blueprint_name = subclass.name ? [subclass.name] : blueprint_name.dup
+    end
+
+    # A descriptive name for the Blueprint view, e.g. "WidgetBlueprint:extended"
+    def self.inspect
+      to_s
+    end
+
+    # A descriptive name for the Blueprint view, e.g. "WidgetBlueprint:extended"
+    def self.to_s
+      blueprint_name.join ':'
+    end
+
+    # Access a child view
+    def self.[](view)
+      views.fetch(view)
+    rescue KeyError
+      raise Blueprinter::Errors::UnknownView, "View '#{view}' could not be found in Blueprint '#{self}'"
+    end
+
+    # Define a new child view, which is a subclass of self
+    def self.view(name, &definition)
+      views[name] = Class.new(self)
+      views[name].blueprint_name << name
+      views[name].class_eval(&definition) if definition
+      views[name]
+    end
+
+    # Define a field
+    # rubocop:todo Lint/UnusedMethodArgument
+    def self.field(name, options = {})
+      fields[name] = 'TODO'
+    end
+
+    # Define an association
+    def self.association(name, blueprint, options = {})
+      fields[name] = 'TODO'
+    end
+
+    def self.render(obj, options = {})
+      new.render(obj, options)
+    end
+
+    def render(obj, options = {})
+      # TODO: call an external Render module/class, passing in self, obj, and options.
+      #
+      # I propose this new renderer (possibly shared with 1.x) would have an "outer" and
+      # "inner" API. The "inner" API would be used when rendering nested Blueprints. The
+      # "outer" API would only be called here.
+      #
+      # This design would allow for some render hooks to only be called ONCE per render (baring
+      # a field/association block calling "render" again), and others to be called on every
+      # nested Blueprint. This would fix some persistent issues with blueprinter-activerecord.
+    end
+  end
+end

spec/v2/name_spec.rb

@@ -0,0 +1,91 @@
+# frozen_string_literal: true
+
+describe "Blueprinter::V2 Names" do
+  context 'const named Blueprints' do
+    class NamedBlueprint < Blueprinter::V2
+      view :extended
+    end
+
+    it 'should have a base name' do
+      expect(NamedBlueprint.to_s).to eq "NamedBlueprint"
+      expect(NamedBlueprint.inspect).to eq "NamedBlueprint"
+    end
+
+    it 'should find a view by name' do
+      expect(NamedBlueprint[:extended].to_s).to eq "NamedBlueprint:extended"
+      expect(NamedBlueprint[:extended].inspect).to eq "NamedBlueprint:extended"
+    end
+
+    it 'should raise for an invalid view name' do
+      expect { NamedBlueprint[:wrong_name] }.to raise_error(
+        Blueprinter::Errors::UnknownView,
+        "View 'wrong_name' could not be found in Blueprint 'NamedBlueprint'"
+      )
+    end
+  end
+
+  context 'manually named Blueprints' do
+    let(:blueprint) do
+      Class.new(Blueprinter::V2) do
+        blueprint_name << "MyBlueprint"
+        view :extended
+      end
+    end
+
+    it 'should have no base name' do
+      expect(blueprint.to_s).to eq "MyBlueprint"
+      expect(blueprint.inspect).to eq "MyBlueprint"
+    end
+
+    it 'should find a view by name' do
+      expect(blueprint[:extended].to_s).to eq "MyBlueprint:extended"
+      expect(blueprint[:extended].inspect).to eq "MyBlueprint:extended"
+    end
+  end
+
+  context 'anonymous Blueprints' do
+    let(:blueprint) do
+      Class.new(Blueprinter::V2) do
+        view :extended
+      end
+    end
+
+    it 'should have no base name' do
+      expect(blueprint.to_s).to eq ""
+      expect(blueprint.inspect).to eq ""
+    end
+
+    it 'should find a view by name' do
+      expect(blueprint[:extended].to_s).to eq "extended"
+      expect(blueprint[:extended].inspect).to eq "extended"
+    end
+  end
+
+  context 'deeply nested Blueprints' do
+    let(:blueprint) do
+      Class.new(Blueprinter::V2) do
+        blueprint_name << "MyBlueprint"
+
+        view :foo do
+          view :bar do
+            view :zorp
+          end
+        end
+      end
+    end
+
+    it 'should find deeply nested names' do
+      expect(blueprint.to_s).to eq "MyBlueprint"
+      expect(blueprint.inspect).to eq "MyBlueprint"
+
+      expect(blueprint[:foo].to_s).to eq "MyBlueprint:foo"
+      expect(blueprint[:foo].inspect).to eq "MyBlueprint:foo"
+
+      expect(blueprint[:foo][:bar].to_s).to eq "MyBlueprint:foo:bar"
+      expect(blueprint[:foo][:bar].inspect).to eq "MyBlueprint:foo:bar"
+
+      expect(blueprint[:foo][:bar][:zorp].to_s).to eq "MyBlueprint:foo:bar:zorp"
+      expect(blueprint[:foo][:bar][:zorp].inspect).to eq "MyBlueprint:foo:bar:zorp"
+    end
+  end
+end