Allow multiparameter assigned attributes to be used with `text_field`

Between 4.2 and 5.0 the behavior of how multiparameter attributes
interact with `_before_type_cast` changed. In 4.2 it returns the
post-type-cast value. After 5.0, it returns the hash that gets sent to
the type. This behavior is correct, but will cause an issue if you then
tried to render that value in an input like `text_field` or
`hidden_field`.

In this case, we want those fields to use the post-type-cast form,
instead of the `_before_type_cast` (the main reason it uses
`_before_type_cast` at all is to avoid losing data when casting a
non-numeric string to integer).

I've opted to modify `came_from_user?` rather than introduce a new
method for this as I want to avoid complicating that contract further,
and technically the multiparameter hash didn't come from assignment, it
was constructed internally by AR.

Close #27888.

2 files changed, 8 insertions, 0 deletions

diff --git a/activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb b/activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb
index e2a8271142..ad891f841e 100644
--- a/activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb
+++ b/activemodel/lib/active_model/type/helpers/accepts_multiparameter_time.rb
@@ -21,6 +21,10 @@ module ActiveModel
             end
           end
 
+          define_method(:value_constructed_by_mass_assignment?) do |value|
+            value.is_a?(Hash)
+          end
+
           define_method(:value_from_multiparameter_assignment) do |values_hash|
             defaults.each do |k, v|
               values_hash[k] ||= v
diff --git a/activemodel/lib/active_model/type/value.rb b/activemodel/lib/active_model/type/value.rb
index a484d9958e..a8ea6a2c22 100644
--- a/activemodel/lib/active_model/type/value.rb
+++ b/activemodel/lib/active_model/type/value.rb
@@ -86,6 +86,10 @@ module ActiveModel
         false
       end
 
+      def value_constructed_by_mass_assignment?(_value) # :nodoc:
+        false
+      end
+
       def map(value) # :nodoc:
         yield value
       end