ZOMG

* we actually should check both variants, with SymbolizeMetadataKeys as
  in the mappers we provide and when transformation is used standalone
  — in case someone composes mappers as they wish

At this point I don't understand why ostruct would always have symbols,
while active_support_time_with_zone would differentiate.

WELP.

Author: mostlyobvious

ruby_event_store/lib/ruby_event_store/mappers/transformation/preserve_types.rb

@@ -143,7 +143,7 @@ def restore_type(argument, type)
           case type
           when Hash
             argument.reduce({}) do |hash, (key, value)|
-              key_type, value_type = type.fetch(key.to_sym)
+              key_type, value_type = type.fetch(key.to_sym) { type.fetch(key.to_s) }
               hash.merge(restore_type(key, key_type) => restore_type(value, value_type))
             end
           when Array

ruby_event_store/spec/mappers/transformation/preserve_types_spec.rb

@@ -113,6 +113,10 @@ module Transformation
             )
         end
 
+        let(:transformation_with_symbolized_metadata) do
+          Pipeline.new(transformation, SymbolizeMetadataKeys.new, to_domain_event: NULL)
+        end
+
         specify "#dump" do
           result = transformation.dump(record)
           expect(result).to eq(dump_of_record)
@@ -338,16 +342,23 @@ module Transformation
               event_id: uuid,
               metadata: {
               },
-              data: active_support_time_with_zone,
+              data: {
+                active_support_time_with_zone: active_support_time_with_zone,
+              },
               event_type: "TestEvent",
               timestamp: nil,
               valid_at: nil,
             )
 
           expect(transformation.dump(record).metadata[:types]).to eq(
-            { data: "ActiveSupport::TimeWithZone", metadata: {} },
+            { data: { "active_support_time_with_zone" => %w[Symbol ActiveSupport::TimeWithZone] }, metadata: {} },
           )
-          expect(transformation.load(transformation.dump(record))).to eq(record)
+          expect(transformation_with_symbolized_metadata.dump(record).metadata[:types]).to eq(
+            { data: { active_support_time_with_zone: %w[Symbol ActiveSupport::TimeWithZone] }, metadata: {} },
+          )
+          [transformation, transformation_with_symbolized_metadata].each do |t|
+            expect(t.load(t.dump(record))).to eq(record)
+          end
         ensure
           Time.zone = current_tz
         end
@@ -365,14 +376,23 @@ module Transformation
               event_id: uuid,
               metadata: {
               },
-              data: ostruct,
+              data: {
+                ostruct: ostruct,
+              },
               event_type: "TestEvent",
               timestamp: nil,
               valid_at: nil,
             )
 
-          expect(transformation.dump(record).metadata[:types]).to eq({ data: "OpenStruct", metadata: {} })
-          expect(transformation.load(transformation.dump(record))).to eq(record)
+          expect(transformation.dump(record).metadata[:types]).to eq(
+            { data: { ostruct: %w[Symbol OpenStruct] }, metadata: {} },
+          )
+          expect(transformation_with_symbolized_metadata.dump(record).metadata[:types]).to eq(
+            { data: { ostruct: %w[Symbol OpenStruct] }, metadata: {} },
+          )
+          [transformation, transformation_with_symbolized_metadata].each do |t|
+            expect(t.load(t.dump(record))).to eq(record)
+          end
         end
 
         specify "handle classes with overloaded name like ActiveSupport::TimeWithZone < 7.1" do