adding test cases for ActiveModel::Errors

Signed-off-by: José Valim <jose.valim@gmail.com>

activemodel/test/cases/errors_test.rb

@@ -0,0 +1,65 @@
+require "cases/helper"
+
+class ErrorsTest < ActiveModel::TestCase
+  class Person
+    extend ActiveModel::Naming
+    def initialize
+      @errors = ActiveModel::Errors.new(self)
+    end
+
+    attr_accessor :name
+    attr_reader   :errors
+
+    def validate!
+      errors.add(:name, "can not be nil") if name == nil
+    end
+
+    def read_attribute_for_validation(attr)
+      send(attr)
+    end
+
+    def self.human_attribute_name(attr, options = {})
+      attr
+    end
+
+    def self.lookup_ancestors
+      [self]
+    end
+
+  end
+
+  test "method validate! should work" do
+    person = Person.new
+    person.validate!
+    assert_equal ["name can not be nil"], person.errors.full_messages
+    assert_equal ["can not be nil"], person.errors[:name]
+
+  end
+
+  test 'should be able to assign error' do
+    person = Person.new
+    person.errors[:name] = 'should not be nil'
+    assert_equal ["should not be nil"], person.errors[:name]
+  end
+
+  test 'should be able to add an error on an attribute' do
+    person = Person.new
+    person.errors.add(:name, "can not be blank")
+    assert_equal ["can not be blank"], person.errors[:name]
+  end
+
+  test 'should respond to size' do
+    person = Person.new
+    person.errors.add(:name, "can not be blank")
+    assert_equal 1, person.errors.size
+  end
+
+  test 'to_a should return an array' do
+    person = Person.new
+    person.errors.add(:name, "can not be blank")
+    person.errors.add(:name, "can not be nil")
+    assert_equal ["name can not be blank", "name can not be nil"], person.errors.to_a
+
+  end
+
+end