Configurable polymorphic class name resolution (#79)

CHANGELOG.MD

@@ -1,3 +1,16 @@
+# Changelog
+
+## Subroutine 4.2.0
+
+If you are using polymorphic association fields, you can now customize how Subroutine
+resolves those class names to a ruby class by setting a global callable/lambda/proc:
+
+```ruby
+::Subroutine.constantize_polymorphic_class_name = ->(class_name) do
+  class_name.classify.constantize
+end
+```
+
 ## Subroutine 4.1.4
 
 Fields using the time/timestamp/datetime caster will now default back to the old behavior, and use a `precision:` option to opt-in to the new behavior introduced in `v4.1.1`.
@@ -16,7 +29,7 @@ to string and re-parsing to a Time object. This fixes issues with losing usec pr
 
 ## Subroutine 4.1.0
 
-A field can no opt out of the natural assignment behavior of ActiveSupport::HashWithIndifferentAccess. Top level param groups are still accessible via indifferent access but if a field sets the `bypass_indifferent_assignment` option to `true` the HashWithIndifferentAccess assignment behavior will be bypassed in favor of direct Hash-like assignment.
+A field can now opt out of the natural assignment behavior of ActiveSupport::HashWithIndifferentAccess. Top level param groups are still accessible via indifferent access but if a field sets the `bypass_indifferent_assignment` option to `true` the HashWithIndifferentAccess assignment behavior will be bypassed in favor of direct Hash-like assignment.
 
 ```ruby
 class MyOp < Subroutine::Op
@@ -37,6 +50,9 @@ The `Subroutine::Fields` module now contains a class_attribute that allows the a
 
 Removed all usage of `ungrouped` params and refactored the storage of grouped params. Params are now stored in either the provided group or the defaults group and accessed via provided_params, params, default_params, and params_with_defaults. Grouped params are accessed the same way but with the group name prefixed eg. `my_private_default_params`.
 
+Polymorphic association fields now resolve class names via `klass.camelize.constantize`,
+previously was `klass.classify.constantize`.
+
 ## Subroutine 3.0
 
 Add support for Rails 6.1. Drop support for Rails 6.0 and lower.

gemfiles/rails_6.1.gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: ..
   specs:
-    subroutine (4.1.5)
+    subroutine (4.2.0)
       activemodel (>= 6.1)
       activesupport (>= 6.1)
 

gemfiles/rails_7.0.gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: ..
   specs:
-    subroutine (4.1.5)
+    subroutine (4.2.0)
       activemodel (>= 6.1)
       activesupport (>= 6.1)
 

gemfiles/rails_7.1.gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: ..
   specs:
-    subroutine (4.1.5)
+    subroutine (4.2.0)
       activemodel (>= 6.1)
       activesupport (>= 6.1)
 

gemfiles/rails_7.2.gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: ..
   specs:
-    subroutine (4.1.5)
+    subroutine (4.2.0)
       activemodel (>= 6.1)
       activesupport (>= 6.1)
 

lib/subroutine.rb

@@ -16,6 +16,18 @@
 
 module Subroutine
 
+  # Used by polymorphic association fields to resolve the class name to a ruby class
+  def self.constantize_polymorphic_class_name(class_name)
+    return @constantize_polymorphic_class_name.call(class_name) if defined?(@constantize_polymorphic_class_name)
+
+    class_name.camelize.constantize
+  end
+
+  # When you need to customize how a polymorphic class name is resolved, you can set this callable/lambda/proc
+  def self.constantize_polymorphic_class_name=(callable)
+    @constantize_polymorphic_class_name = callable
+  end
+
   def self.include_defaults_in_params=(bool)
     @include_defaults_in_params = !!bool
   end

lib/subroutine/association_fields.rb

@@ -177,7 +177,7 @@ def fetch_association_instance(config)
           get_field(config.foreign_type_method)
         end
 
-      klass = klass.camelize.constantize if klass.is_a?(String)
+      klass = Subroutine.constantize_polymorphic_class_name(klass) if klass.is_a?(String)
       return nil unless klass
 
       foreign_key = config.foreign_key_method

lib/subroutine/version.rb

@@ -3,8 +3,8 @@
 module Subroutine
 
   MAJOR = 4
-  MINOR = 1
-  PATCH = 5
+  MINOR = 2
+  PATCH = 0
   PRE   = nil
 
   VERSION = [MAJOR, MINOR, PATCH, PRE].compact.join(".")