check for valid options in validate method

This change prevents a certain class of user error which results when
mistakenly using the `validate` class method instead of the `validates`
class method.

Only apply when all arguments are symbols, because some validations use
the `validate` method and pass in additional options, namely the
`LenghValidator` via the `ActiveMode::Validations::validates_with`
method.

1 files changed, 6 insertions, 0 deletions

diff --git a/activemodel/test/cases/validations_test.rb b/activemodel/test/cases/validations_test.rb
index 4fee704ef5..948efd0f0a 100644
--- a/activemodel/test/cases/validations_test.rb
+++ b/activemodel/test/cases/validations_test.rb
@@ -167,6 +167,12 @@ class ValidationsTest < ActiveModel::TestCase
     end
   end
 
+  def test_invalid_options_to_validate
+    assert_raises(ArgumentError) do
+      Topic.validate :title, presence: true
+    end
+  end
+
   def test_errors_conversions
     Topic.validates_presence_of %w(title content)
     t = Topic.new