4 files changed, 75 insertions, 1 deletions
diff --git a/activemodel/test/cases/conversion_test.rb b/activemodel/test/cases/conversion_test.rb
index d679ad41aa..a037666cbc 100644
--- a/activemodel/test/cases/conversion_test.rb
+++ b/activemodel/test/cases/conversion_test.rb
@@ -29,4 +29,8 @@ class ConversionTest < ActiveModel::TestCase
     assert_equal "helicopters/helicopter", Helicopter.new.to_partial_path,
       "ActiveModel::Conversion#to_partial_path caching should be class-specific"
   end
+
+  test "to_partial_path handles namespaced models" do
+    assert_equal "helicopter/comanches/comanche", Helicopter::Comanche.new.to_partial_path
+  end
 end
diff --git a/activemodel/test/cases/dirty_test.rb b/activemodel/test/cases/dirty_test.rb
index 0b9f9537e2..ba45089cca 100644
--- a/activemodel/test/cases/dirty_test.rb
+++ b/activemodel/test/cases/dirty_test.rb
@@ -46,7 +46,7 @@ class DirtyTest < ActiveModel::TestCase
     assert @model.name_changed?
   end
 
-  test "list of changed attributes" do
+  test "list of changed attribute keys" do
     assert_equal [], @model.changed
     @model.name = "Paul"
     assert_equal ['name'], @model.changed
@@ -106,6 +106,17 @@ class DirtyTest < ActiveModel::TestCase
     assert_equal [nil, "Jericho Cane"], @model.previous_changes['name']
   end
 
+  test "previous value is preserved when changed after save" do
+    assert_equal({}, @model.changed_attributes)
+    @model.name = "Paul"
+    assert_equal({ "name" => nil }, @model.changed_attributes)
+
+    @model.save
+
+    @model.name = "John"
+    assert_equal({ "name" => "Paul" }, @model.changed_attributes)
+  end
+
   test "changing the same attribute multiple times retains the correct original value" do
     @model.name = "Otto"
     @model.save
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index 1ffce1ae47..cc0c3f16d2 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -54,6 +54,59 @@ class ErrorsTest < ActiveModel::TestCase
     assert errors.has_key?(:foo), 'errors should have key :foo'
   end
 
+  test "should be able to clear the errors" do
+    person = Person.new
+    person.validate!
+
+    assert_equal 1, person.errors.count
+    person.errors.clear
+    assert person.errors.empty?
+  end
+
+  test "get returns the error by the provided key" do
+    errors = ActiveModel::Errors.new(self)
+    errors[:foo] = "omg"
+
+    assert_equal ["omg"], errors.get(:foo)
+  end
+
+  test "sets the error with the provided key" do
+    errors = ActiveModel::Errors.new(self)
+    errors.set(:foo, "omg")
+
+    assert_equal({ foo: "omg" }, errors.messages)
+  end
+
+  test "values returns an array of messages" do
+    errors = ActiveModel::Errors.new(self)
+    errors.set(:foo, "omg")
+    errors.set(:baz, "zomg")
+
+    assert_equal ["omg", "zomg"], errors.values
+  end
+
+  test "keys returns the error keys" do
+    errors = ActiveModel::Errors.new(self)
+    errors.set(:foo, "omg")
+    errors.set(:baz, "zomg")
+
+    assert_equal [:foo, :baz], errors.keys
+  end
+
+  test "as_json returns a json formatted representation of the errors hash" do
+    person = Person.new
+    person.validate!
+
+    assert_equal({ name: ["can not be nil"] }, person.errors.as_json)
+  end
+
+  test "as_json with :full_messages option" do
+    person = Person.new
+    person.validate!
+
+    assert_equal({ name: ["name can not be nil"] }, person.errors.as_json(full_messages: true))
+  end
+
   test "should return true if no errors" do
     person = Person.new
     person.errors[:foo]
diff --git a/activemodel/test/cases/model_test.rb b/activemodel/test/cases/model_test.rb
index d93fd96b88..588d8e661e 100644
--- a/activemodel/test/cases/model_test.rb
+++ b/activemodel/test/cases/model_test.rb
@@ -20,7 +20,13 @@ class ModelTest < ActiveModel::TestCase
   def test_initialize_with_nil_or_empty_hash_params_does_not_explode
     assert_nothing_raised do
       BasicModel.new()
+      BasicModel.new nil
       BasicModel.new({})
     end
   end
+
+  def test_persisted_is_always_false
+    object = BasicModel.new(:attr => "value")
+    assert object.persisted? == false
+  end
 end