Hack around dubious error usage

config/locales/de.yml

@@ -1700,6 +1700,6 @@ de:
         invalid_user_assigned_to_work_package:
           "Der gewählte Nutzer darf dem Arbeitspaket nicht als '%{property}' zugewiesen werden."
         estimated_hours: "Der geschätzte Aufwand kann für Eltern-Arbeitspakete nicht gesetzt werden."
-        done_ratio: "Der Fortschritt von Eltern-Arbeitspaketen kann nicht gesetzt werden."
+        done_ratio: "Der Fortschritt kann nicht gesetzt werden falls es sich um ein Eltern-Arbeitspaket handelt, er durch den Status definiert wird oder wenn er komplett deaktiviert wurde."
     resources:
       schema: 'Schema'

config/locales/en.yml

@@ -1690,8 +1690,6 @@ en:
         invalid_user_assigned_to_work_package:
           "The chosen user is not allowed to be '%{property}' for this work package."
         estimated_hours: "Estimated hours cannot be set on parent work packages."
-        done_ratio_readonly_parent: "Done ratio cannot be set on parent work packages."
-        done_ratio_readonly_status: "Done ratio cannot be set when it is inferred by status."
-        done_ratio_disabled: "Done ratio cannot be set when it is disabled."
+        done_ratio: "Done ratio cannot be set on parent work packages, when it is inferred by status or when it is disabled."
     resources:
       schema: 'Schema'

lib/api/errors/error_base.rb

@@ -43,7 +43,7 @@ module API
             when :error_conflict
               return ::API::Errors::Conflict
             when :error_readonly
-              return ::API::Errors::UnwritableProperty.new(errors[key])
+              return ::API::Errors::UnwritableProperty.new(errors[key].flatten)
             end
           end
         end

lib/api/errors/unwritable_property.rb

@@ -36,7 +36,14 @@ module API
         fail ArgumentError, 'UnwritableProperty error must contain at least one invalid attribute!' if attributes.empty?
 
         if attributes.length == 1
-          message = I18n.t('api_v3.errors.writing_read_only_attributes')
+          message = case attributes.first
+                    when 'estimated_hours'
+                      I18n.t('api_v3.errors.validation.estimated_hours')
+                    when 'done_ratio'
+                      I18n.t('api_v3.errors.validation.done_ratio')
+                    else
+                      I18n.t('api_v3.errors.writing_read_only_attributes')
+                    end
         else
           message = I18n.t('api_v3.errors.multiple_errors')
         end
@@ -48,8 +55,8 @@ module API
 
       def evaluate_attributes(attributes, invalid_attributes)
         if attributes.length > 1
-          invalid_attributes.each do |error|
-            @errors << UnwritableProperty.new(error)
+          invalid_attributes.each do |attribute|
+            @errors << UnwritableProperty.new(attribute)
           end
         else
           @details = { attribute: attributes[0].to_s.camelize(:lower) }

lib/api/v3/work_packages/work_package_contract.rb

@@ -102,9 +102,7 @@ module API
         def readonly_attributes_unchanged
           changed_attributes = model.changed - self.class.writable_attributes
 
-          changed_attributes.each do |attribute|
-            errors.add attribute.to_sym, I18n.t('api_v3.errors.writing_read_only_attributes')
-          end unless changed_attributes.empty?
+          errors.add :error_readonly, changed_attributes unless changed_attributes.empty?
         end
 
         def assignee_visible
@@ -117,20 +115,19 @@ module API
 
         def estimated_hours_valid
           if !model.leaf? && model.changed.include?('estimated_hours')
-            errors.add :estimated_time, I18n.t('api_v3.errors.validation.estimated_hours')
+            errors.add :error_readonly, 'estimated_hours'
           end
         end
 
         def done_ratio_valid
           if model.changed.include?('done_ratio')
+            # TODO Allow multiple errors as soon as they have separate messages
             if !model.leaf?
-              errors.add :done_ratio, I18n.t('api_v3.errors.validation.done_ratio_readonly_parent')
-            end
-            if Setting.work_package_done_ratio == 'status'
-              errors.add :done_ratio, I18n.t('api_v3.errors.validation.done_ratio_readonly_status')
-            end
-            if Setting.work_package_done_ratio == 'disabled'
-              errors.add :done_ratio, I18n.t('api_v3.errors.validation.done_ratio_disabled')
+              errors.add :error_readonly, 'done_ratio'
+            elsif Setting.work_package_done_ratio == 'status'
+              errors.add :error_readonly, 'done_ratio'
+            elsif Setting.work_package_done_ratio == 'disabled'
+              errors.add :error_readonly, 'done_ratio'
             end
           end
         end

spec/requests/api/v3/work_package_resource_spec.rb

@@ -763,7 +763,7 @@ h4. things we like
 
           it_behaves_like 'multiple errors', 422
 
-          it_behaves_like 'multiple errors of the same type', 2, 'PropertyIsReadOnly'
+          it_behaves_like 'multiple errors of the same type', 2, 'PropertyConstraintViolation'
 
           it_behaves_like 'multiple errors of the same type with messages' do
             let(:message) { ['Subject can\'t be blank.', 'Parent does not exist.'] }
@@ -811,7 +811,7 @@ h4. things we like
 
           it_behaves_like 'multiple errors', 422, 'Multiple fields violated their constraints.'
 
-          it_behaves_like 'multiple errors of the same type', 2, 'PropertyIsReadOnly'
+          it_behaves_like 'multiple errors of the same type', 2, 'PropertyConstraintViolation'
 
           it_behaves_like 'multiple errors of the same type with messages' do
             let(:message) {