Issue #48. Add tests about apply_to_nil

lib/tramway/base_form.rb

@@ -62,16 +62,22 @@ def respond_to_missing?(method_name, include_private = false)
     private
 
     def __submit(params)
-      values = params
+      __apply_properties __apply_normalizations params
+    end
 
-      self.class.normalizations.each do |attribute, normalization|
-        if params.key?(attribute) || normalization[:apply_to_nil]
-          values[attribute] = instance_exec(params[attribute], &normalization[:proc])
+    def __apply_normalizations(params)
+      self.class.normalizations.reduce(params) do |hash, (attribute, normalization)|
+        if hash.key?(attribute) || normalization[:apply_to_nil]
+          hash.merge(attribute => instance_exec(hash[attribute], &normalization[:proc]))
+        else
+          hash
         end
       end
+    end
 
+    def __apply_properties(params)
       self.class.properties.each do |attribute|
-        public_send("#{attribute}=", values[attribute]) if values.key?(attribute)
+        public_send("#{attribute}=", params[attribute]) if params.key?(attribute)
       end
     end
 

lib/tramway/forms/normalizations.rb

@@ -5,6 +5,7 @@ module Forms
     # This is the same `normalizes` feature like in Rails
     # https://api.rubyonrails.org/v7.1/classes/ActiveRecord/Normalization/ClassMethods.html#method-i-normalizes
     module Normalizations
+      # :reek:BooleanParameter { enabled: false }
       def normalizes(*attributes, with:, apply_to_nil: false)
         attributes.each do |attribute|
           @normalizations.merge!(attribute => { proc: with, apply_to_nil: })

spec/dummy/app/forms/admin_form.rb

@@ -5,5 +5,5 @@ class AdminForm < UserForm
   properties :permissions, :first_name, :last_name
 
   normalizes :permissions, with: ->(value) { value.is_a?(Array) ? value : value.split(',') }
-  normalizes :first_name, :last_name, with: ->(value) { value.strip }
+  normalizes :first_name, :last_name, with: ->(value) { value&.strip }
 end

spec/dummy/app/forms/user_form.rb

@@ -4,5 +4,5 @@
 class UserForm < Tramway::BaseForm
   properties :email, :role
 
-  normalizes :email, with: ->(value) { value.strip.downcase }
+  normalizes :email, with: ->(value) { value&.strip&.downcase }
 end

spec/dummy/db/migrate/20230627061428_create_users.rb

@@ -3,10 +3,10 @@
 class CreateUsers < ActiveRecord::Migration[7.0]
   def change
     create_table :users do |t|
-      t.string :email,              null: false, default: ''
-      t.string :first_name,         null: false, default: ''
-      t.string :last_name,          null: false, default: ''
-      t.string :encrypted_password, null: false, default: ''
+      t.string :email
+      t.string :first_name
+      t.string :last_name
+      t.string :encrypted_password
 
       t.string   :reset_password_token
       t.datetime :reset_password_sent_at

spec/dummy/db/schema.rb

@@ -22,10 +22,10 @@
   end
 
   create_table 'users', force: :cascade do |t|
-    t.string 'email', default: '', null: false
-    t.string 'first_name', default: '', null: false
-    t.string 'last_name', default: '', null: false
-    t.string 'encrypted_password', default: '', null: false
+    t.string 'email'
+    t.string 'first_name'
+    t.string 'last_name'
+    t.string 'encrypted_password'
     t.string 'reset_password_token'
     t.datetime 'reset_password_sent_at'
     t.datetime 'remember_created_at'

spec/forms/normalizes_form_spec.rb

@@ -18,6 +18,23 @@
         expect(user.last_name).to eq 'Selezneva'
       end
     end
+
+    context 'when normalizing attributes with apply_on_nil: true' do
+      it 'applies normalization to nil values' do
+        AdminForm.new(user).submit(first_name: nil, last_name: nil)
+
+        expect(user.first_name).to be_nil
+        expect(user.last_name).to be_nil
+      end
+    end
+
+    context 'when normalizing attributes without apply_on_nil' do
+      it 'does not apply normalization to nil values' do
+        UserForm.new(user).submit(email: nil)
+
+        expect(user.email).to eq nil
+      end
+    end
   end
 
   context 'inheritance and extension' do