Apply key transforms to keys referenced in values

test/adapter/json/transform_test.rb

@@ -0,0 +1,93 @@
+require 'test_helper'
+
+module ActiveModelSerializers
+  module Adapter
+    class Json
+      class KeyCaseTest < ActiveSupport::TestCase
+        def mock_request(key_transform = nil)
+          context = Minitest::Mock.new
+          context.expect(:request_url, URI)
+          context.expect(:query_parameters, {})
+          @options = {}
+          @options[:key_transform] = key_transform if key_transform
+          @options[:serialization_context] = context
+        end
+
+        Post = Class.new(::Model)
+        class PostSerializer < ActiveModel::Serializer
+          attributes :id, :title, :body, :publish_at
+        end
+
+        def setup
+          ActionController::Base.cache_store.clear
+          @blog = Blog.new(id: 1, name: 'My Blog!!', special_attribute: 'neat')
+          serializer = CustomBlogSerializer.new(@blog)
+          @adapter = ActiveModelSerializers::Adapter::Json.new(serializer)
+        end
+
+        def test_transform_default
+          mock_request
+          assert_equal({
+            blog: { id: 1, special_attribute: 'neat', articles: nil }
+          }, @adapter.serializable_hash(@options))
+        end
+
+        def test_transform_global_config
+          mock_request
+          result = with_config(key_transform: :camel_lower) do
+            @adapter.serializable_hash(@options)
+          end
+          assert_equal({
+            blog: { id: 1, specialAttribute: 'neat', articles: nil }
+          }, result)
+        end
+
+        def test_transform_serialization_ctx_overrides_global_config
+          mock_request(:camel)
+          result = with_config(key_transform: :camel_lower) do
+            @adapter.serializable_hash(@options)
+          end
+          assert_equal({
+            Blog: { Id: 1, SpecialAttribute: 'neat', Articles: nil }
+          }, result)
+        end
+
+        def test_transform_undefined
+          mock_request(:blam)
+          result = nil
+          assert_raises NoMethodError do
+            result = @adapter.serializable_hash(@options)
+          end
+        end
+
+        def test_transform_dash
+          mock_request(:dash)
+          assert_equal({
+            blog: { id: 1, :"special-attribute" => 'neat', articles: nil }
+          }, @adapter.serializable_hash(@options))
+        end
+
+        def test_transform_unaltered
+          mock_request(:unaltered)
+          assert_equal({
+            blog: { id: 1, special_attribute: 'neat', articles: nil }
+          }, @adapter.serializable_hash(@options))
+        end
+
+        def test_transform_camel
+          mock_request(:camel)
+          assert_equal({
+            Blog: { Id: 1, SpecialAttribute: 'neat', Articles: nil }
+          }, @adapter.serializable_hash(@options))
+        end
+
+        def test_transform_camel_lower
+          mock_request(:camel_lower)
+          assert_equal({
+            blog: { id: 1, specialAttribute: 'neat', articles: nil }
+          }, @adapter.serializable_hash(@options))
+        end
+      end
+    end
+  end
+end