Add some tests

Author: kieraneglin

spec/dummy/app/controllers/inertia_prop_transformer_controller.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+class InertiaPropTransformerController < ApplicationController
+  inertia_config(
+    prop_transformer: lambda do |props:|
+      props.deep_transform_keys { |key| key.to_s.upcase }
+    end
+  )
+
+  def just_props
+    render inertia: 'TestComponent', props: {
+      lower_prop: 'lower_value',
+      parent_hash: {
+        lower_child_prop: 'lower_child_value',
+      },
+    }
+  end
+
+  def props_and_meta
+    render inertia: 'TestComponent',
+           props: {
+             lower_prop: 'lower_value',
+           },
+           meta: [
+             { name: 'description', content: "Don't transform me!" }
+           ]
+  end
+
+  def no_props
+    render inertia: 'TestComponent'
+  end
+end

spec/dummy/config/routes.rb

@@ -42,6 +42,9 @@
   get 'instance_props_test' => 'inertia_rails_mimic#instance_props_test'
   get 'default_render_test' => 'inertia_rails_mimic#default_render_test'
   get 'transformed_default_render_test' => 'transformed_inertia_rails_mimic#render_test'
+  get 'prop_transformer_test' => 'inertia_prop_transformer#just_props'
+  get 'prop_transformer_with_meta_test' => 'inertia_prop_transformer#props_and_meta'
+  get 'prop_transformer_no_props_test' => 'inertia_prop_transformer#no_props'
   get 'default_component_test' => 'inertia_rails_mimic#default_component_test'
   get 'default_component_with_props_test' => 'inertia_rails_mimic#default_component_with_props_test'
   get 'default_component_with_duplicated_props_test' => 'inertia_rails_mimic#default_component_with_duplicated_props_test'

spec/inertia/prop_transformer_spec.rb

@@ -0,0 +1,60 @@
+# frozen_string_literal: true
+
+require_relative '../../lib/inertia_rails/rspec'
+RSpec.describe 'props can be transformed', type: :request, inertia: true do
+  let(:headers) do
+    {
+      'X-Inertia' => true,
+      'X-Inertia-Partial-Component' => 'TestComponent',
+    }
+  end
+
+  context 'props are provided' do
+    it 'transforms the props' do
+      get prop_transformer_test_path, headers: headers
+
+      expect_inertia.to render_component('TestComponent')
+        .and have_exact_props({
+          'LOWER_PROP' => 'lower_value',
+          'PARENT_HASH' => {
+            'LOWER_CHILD_PROP' => 'lower_child_value',
+          },
+        })
+    end
+  end
+
+  context 'props and meta are provided' do
+    it 'transforms the props' do
+      get prop_transformer_with_meta_test_path, headers: headers
+
+      expect_inertia.to render_component('TestComponent')
+        .and include_props({
+          'LOWER_PROP' => 'lower_value',
+        })
+    end
+
+    it 'does not transform the meta' do
+      get prop_transformer_with_meta_test_path, headers: headers
+
+      expect(response.parsed_body['props']['_inertia_meta']).to eq(
+        [
+          {
+            'tagName' => 'meta',
+            'name' => 'description',
+            'content' => "Don't transform me!",
+            'headKey' => 'meta-name-description',
+          }
+        ]
+      )
+    end
+  end
+
+  context 'no props are provided' do
+    it 'does not error' do
+      get prop_transformer_no_props_test_path, headers: headers
+
+      expect_inertia.to render_component('TestComponent')
+        .and have_exact_props({})
+    end
+  end
+end