Detect enum fields as Selects rather than as Strings (#1655)

* Fixes thoughtbot/administrate#1629

* Define enum collection option as a proc

* make proc regexp better

Co-authored-by: Tadeusz Niemiec <tadeusz@applover.pl>

lib/administrate/field/select.rb

@@ -14,10 +14,12 @@ def selectable_options
       private
 
       def collection
-        maybe_proc = options.fetch(:collection, [])
-        return maybe_proc.call if maybe_proc.respond_to? :call
+        values = options.fetch(:collection, [])
+        if values.respond_to? :call
+          return values.arity.positive? ? values.call(self) : values.call
+        end
 
-        @collection ||= maybe_proc
+        @collection ||= values
       end
     end
   end

lib/generators/administrate/dashboard/dashboard_generator.rb

@@ -7,7 +7,7 @@ class DashboardGenerator < Rails::Generators::NamedBase
         boolean: "Field::Boolean",
         date: "Field::Date",
         datetime: "Field::DateTime",
-        enum: "Field::String",
+        enum: "Field::Select",
         float: "Field::Number",
         integer: "Field::Number",
         time: "Field::Time",
@@ -16,7 +16,9 @@ class DashboardGenerator < Rails::Generators::NamedBase
       }
 
       ATTRIBUTE_OPTIONS_MAPPING = {
-        enum: { searchable: false },
+        # procs must be defined in one line!
+        enum: {  searchable: false,
+                 collection: ->(field) { field.resource.class.send(field.attribute.to_s.pluralize).keys } },
         float: { decimals: 2 },
       }
 
@@ -136,7 +138,16 @@ def options_string(options)
       end
 
       def inspect_hash_as_ruby(hash)
-        hash.map { |key, value| "#{key}: #{value.inspect}" }.join(", ")
+        hash.map do |key, value|
+          v_str = value.respond_to?(:call) ? proc_string(value) : value.inspect
+          "#{key}: #{v_str}"
+        end.join(", ")
+      end
+
+      def proc_string(value)
+        source = value.source_location
+        proc_string = IO.readlines(source.first)[source.second - 1]
+        proc_string[/->[^}]*} | (lambda|proc).*end/x]
       end
     end
   end

spec/generators/dashboard_generator_spec.rb

@@ -130,28 +130,52 @@ class InventoryItem < ApplicationRecord
         end
       end
 
-      it "detects enum field as `String`" do
-        begin
-          ActiveRecord::Schema.define do
-            create_table :shipments do |t|
-              t.integer :status
-            end
+      it "detects enum field as `Select`" do
+        ActiveRecord::Schema.define do
+          create_table :shipments do |t|
+            t.integer :status
           end
+        end
 
-          class Shipment < ApplicationRecord
-            enum status: [:ready, :processing, :shipped]
-            reset_column_information
-          end
+        class Shipment < ApplicationRecord
+          enum status: %i[ready processing shipped]
+          reset_column_information
+        end
 
-          run_generator ["shipment"]
-          load file("app/dashboards/shipment_dashboard.rb")
-          attrs = ShipmentDashboard::ATTRIBUTE_TYPES
+        run_generator ["shipment"]
+        load file("app/dashboards/shipment_dashboard.rb")
+        attrs = ShipmentDashboard::ATTRIBUTE_TYPES
 
-          expect(attrs[:status]).
-            to eq(Administrate::Field::String.with_options(searchable: false))
-        ensure
-          remove_constants :Shipment, :ShipmentDashboard
+        expect(attrs[:status].deferred_class).to eq(Administrate::Field::Select)
+      ensure
+        remove_constants :Shipment, :ShipmentDashboard
+      end
+
+      it "handles collection procs option in the 'Select' field" do
+        ActiveRecord::Schema.define do
+          create_table :shipments do |t|
+            t.integer :status
+          end
         end
+
+        class Shipment < ApplicationRecord
+          enum status: %i[ready processing shipped]
+          reset_column_information
+        end
+
+        run_generator ["shipment"]
+        load file("app/dashboards/shipment_dashboard.rb")
+        attrs = ShipmentDashboard::ATTRIBUTE_TYPES
+        enum_collection_option = attrs[:status].options[:collection]
+        select_field = Administrate::Field::Select.new(:status,
+                                                       nil,
+                                                       attrs[:status].options,
+                                                       resource: Shipment.new)
+
+        expect(enum_collection_option.call(select_field)).
+          to eq(Shipment.statuses.keys)
+      ensure
+        remove_constants :Shipment, :ShipmentDashboard
       end
 
       it "detects boolean values" do