[~] fix copilot review comment & enable cache globally for test env

Author: skcc321

lib/mongoid/fields.rb

@@ -686,8 +686,8 @@ def create_accessors(name, meth, options = {})
       def create_field_getter(name, meth, field)
         generated_methods.module_eval do
           re_define_method(meth) do
+            # Handle lazy defaults first (before reading raw value)
             raw = read_raw_attribute(name)
-            # Handle lazy defaults outside of cache to avoid recursive locking
             if lazy_settable?(field, raw)
               write_attribute(name, field.eval_default(self))
             # Don't cache localized fields as they depend on I18n.locale
@@ -698,9 +698,10 @@ def create_field_getter(name, meth, field)
               # Atomically fetch or compute the cached value
               # Cache stores [raw_value, demongoized_value] to detect stale cache
               value = @__demongoized_cache.compute_if_absent(name) do
-                # Cache miss - compute and store
-                demongoized = process_raw_attribute(name.to_s, raw, field)
-                [raw, demongoized]
+                # Cache miss - re-read raw inside block to avoid race conditions
+                current_raw = read_raw_attribute(name)
+                demongoized = process_raw_attribute(name.to_s, current_raw, field)
+                [current_raw, demongoized]
               end
 
               # Check if cached raw value matches current raw value

spec/spec_helper.rb

@@ -126,6 +126,8 @@ def test_model(name: 'TestModel', &block)
 # Set the database that the spec suite connects to.
 Mongoid.configure do |config|
   config.load_configuration(CONFIG)
+  # Enable cache for all tests
+  config.cache_attribute_values = true
 end
 
 # Autoload every model for the test suite that sits in spec/support/models.