Adds/Corrects use case for adding an error message

I believe this is a use case that was supposed to be supported, and it's
a small fix.

2 files changed, 7 insertions, 1 deletions

diff --git a/activemodel/lib/active_model/errors.rb b/activemodel/lib/active_model/errors.rb
index f843b279ce..287a2559d2 100644
--- a/activemodel/lib/active_model/errors.rb
+++ b/activemodel/lib/active_model/errors.rb
@@ -452,7 +452,6 @@ module ActiveModel
         defaults = []
       end
 
-      defaults << options.delete(:message)
       defaults << :"#{@base.class.i18n_scope}.errors.messages.#{type}" if @base.class.respond_to?(:i18n_scope)
       defaults << :"errors.attributes.#{attribute}.#{type}"
       defaults << :"errors.messages.#{type}"
@@ -461,6 +460,7 @@ module ActiveModel
       defaults.flatten!
 
       key = defaults.shift
+      defaults = options.delete(:message) if options[:message]
       value = (attribute != :base ? @base.send(:read_attribute_for_validation, attribute) : nil)
 
       options = {
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index f781a0017f..d10c20caad 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -149,6 +149,12 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal ["cannot be blank"], person.errors[:name]
   end
 
+  test "add an error message on a specific attribute with a defined type" do
+    person = Person.new
+    person.errors.add(:name, :blank, message: "cannot be blank")
+    assert_equal ["cannot be blank"], person.errors[:name]
+  end
+
   test "add an error with a symbol" do
     person = Person.new
     person.errors.add(:name, :blank)