refactor: cache resolved shared data and config in controller classes

Shared data is now frozen to prevent

Also, match the method names for instance variables.

Updated a test that used to call `inertia_share` inside a `before_action`
as that seems like something a user should never do.

Author: ElMassimo

lib/inertia_rails/configuration.rb

@@ -32,10 +32,20 @@ def bind_controller(controller)
       Configuration.new(**@options, controller: controller)
     end
 
+    def freeze
+      @options.freeze
+      super
+    end
+
     def to_h
       @options.to_h
     end
 
+    def merge!(config)
+      @options.merge!(config.options)
+      self
+    end
+
     def merge(config)
       Configuration.new(**@options.merge(config.options))
     end

lib/inertia_rails/controller.rb

@@ -15,18 +15,18 @@ module Controller
 
     module ClassMethods
       def inertia_share(**attrs, &block)
-        @inertia_shared_data ||= []
-        @inertia_shared_data << attrs unless attrs.empty?
-        @inertia_shared_data << block if block
+        @inertia_share ||= []
+        @inertia_share << attrs.freeze unless attrs.empty?
+        @inertia_share << block if block
       end
 
       def inertia_config(**attrs)
         config = InertiaRails::Configuration.new(**attrs)
 
-        if @inertia_configuration
-          @inertia_configuration.merge!(config)
+        if @inertia_config
+          @inertia_config.merge!(config)
         else
-          @inertia_configuration = config
+          @inertia_config = config
         end
       end
 
@@ -38,12 +38,14 @@ def use_inertia_instance_props
       end
 
       def _inertia_configuration
-        config = superclass.try(:_inertia_configuration) || ::InertiaRails.configuration
-        @inertia_configuration ? config.merge(@inertia_configuration) : config
+        @_inertia_configuration ||= begin
+          config = superclass.try(:_inertia_configuration) || ::InertiaRails.configuration
+          @inertia_config ? config.merge(@inertia_config).freeze : config
+        end
       end
 
       def _inertia_shared_data
-        [*superclass.try(:_inertia_shared_data), *@inertia_shared_data]
+        @_inertia_shared_data ||= [*superclass.try(:_inertia_shared_data), *@inertia_share].freeze
       end
     end
 

spec/dummy/app/controllers/inertia_conditional_sharing_controller.rb

@@ -1,7 +1,10 @@
 class InertiaConditionalSharingController < ApplicationController
-  before_action :conditionally_share_props, only: [:show]
   inertia_share normal_shared_prop: 1
 
+  inertia_share do
+    {conditionally_shared_show_prop: 1} if action_name == "show"
+  end
+
   def index
     render inertia: 'EmptyTestComponent', props: {
       index_only_prop: 1,
@@ -13,10 +16,4 @@ def show
       show_only_prop: 1,
     }
   end
-
-  protected
-
-  def conditionally_share_props
-    self.class.inertia_share conditionally_shared_show_prop: 1
-  end
 end

spec/dummy/app/controllers/inertia_config_test_controller.rb

@@ -7,6 +7,11 @@ class InertiaConfigTestController < ApplicationController
     version: "2.0",
   )
 
+  # Test that modules included in the same class can also call it.
+  inertia_config(
+    version: "2.0",
+  )
+
   def configuration
     render json: inertia_configuration.to_h
   end

spec/inertia/conditional_sharing_spec.rb

@@ -1,6 +1,6 @@
 RSpec.describe "conditionally shared data in a controller", type: :request do
-  context "when there is a before_action inside a inertia_share" do
-    it "does leak data between requests" do
+  context "when there is conditional data inside inertia_share" do
+    it "does not leak data between requests" do
       get conditional_share_index_path, headers: {'X-Inertia' => true}
       expect(JSON.parse(response.body)['props'].deep_symbolize_keys).to eq({
                                                                              index_only_prop: 1,
@@ -22,7 +22,6 @@
       expect(JSON.parse(response.body)['props'].deep_symbolize_keys).to eq({
                                                                              index_only_prop: 1,
                                                                              normal_shared_prop: 1,
-                                                                             conditionally_shared_show_prop: 1,
                                                                            })
     end
   end

spec/inertia/configuration_spec.rb

@@ -1,6 +1,23 @@
 RSpec.describe 'Inertia configuration', type: :request do
   after { reset_config! }
 
+  describe "InertiaRails::Configuration" do
+    it "does not allow to modify options after frozen" do
+      config = InertiaRails::Configuration.default
+      config.ssr_enabled = true
+      expect(config.ssr_enabled).to eq true
+
+      config.freeze
+      expect { config.ssr_enabled = false }.to raise_error(FrozenError)
+      expect { config.merge!(InertiaRails::Configuration.default) }.to raise_error(FrozenError)
+
+      expect {
+        merged_config = config.merge(InertiaRails::Configuration.default)
+        expect(merged_config.ssr_enabled).to eq false
+      }.not_to raise_error
+    end
+  end
+
   describe 'inertia_config' do
     it 'overrides the global values' do
       get configuration_path