allow_value.with_message takes i18n interp values

NEWS.md

@@ -1,5 +1,13 @@
 # HEAD
 
+## Features
+
+* Teach `with_message` qualifier on `allow_value` to accept a hash of i18n
+  interpolation values:
+  `allow_value('foo').for(:attr).with_message(:greater_than, values: { count: 20 })`.
+
+## Bug fixes
+
 * Fix `ComparisonMatcher` so that `validate_numericality_of` comparison matchers
   work with large numbers.
 

lib/shoulda/matchers/active_model/allow_value_matcher.rb

@@ -53,9 +53,12 @@ module Shoulda # :nodoc:
 
         def with_message(message, options={})
           self.options[:expected_message] = message
+          self.options[:expected_message_values] = options.fetch(:values, {})
+
           if options.key?(:against)
             self.attribute_to_check_message_against = options[:against]
           end
+
           self
         end
 
@@ -173,10 +176,18 @@ module Shoulda # :nodoc:
         def default_attribute_message
           default_error_message(
             options[:expected_message],
+            default_attribute_message_values
+          )
+        end
+
+        def default_attribute_message_values
+          defaults = {
             model_name: model_name,
             instance: instance,
-            attribute: attribute_to_set
-          )
+            attribute: attribute_to_set,
+          }
+
+          defaults.merge(options[:expected_message_values])
         end
 
         def model_name

spec/shoulda/matchers/active_model/allow_value_matcher_spec.rb

@@ -68,6 +68,24 @@ describe Shoulda::Matchers::ActiveModel::AllowValueMatcher do
       expect(validating_format(with: /abc/, message: 'bad value')).
         not_to allow_value('xyz').for(:attr).with_message(/bad/)
     end
+
+    it 'allows interpolation values for the message to be provided' do
+      options = {
+        attribute_name: :attr,
+        attribute_type: :string
+      }
+
+      record = record_with_custom_validation(options) do
+        if self.attr == 'xyz'
+          self.errors.add :attr, :greater_than, count: 2
+        end
+      end
+
+      expect(record).
+        not_to allow_value('xyz').
+        for(:attr).
+        with_message(:greater_than, values: { count: 2 })
+    end
   end
 
   context 'an attribute where the message occurs on another attribute' do

spec/support/activemodel_helpers.rb

@@ -1,11 +1,15 @@
 module ActiveModelHelpers
-  def custom_validation(&block)
-    define_model(:example, attr: :integer) do
+  def custom_validation(options = {}, &block)
+    attribute_name = options.fetch(:attribute_name, :attr)
+    attribute_type = options.fetch(:attribute_type, :integer)
+
+    define_model(:example, attribute_name => attribute_type) do
       validate :custom_validation
 
       define_method(:custom_validation, &block)
     end.new
   end
+  alias record_with_custom_validation custom_validation
 
   def validating_format(options)
     define_model :example, attr: :string do