1 files changed, 163 insertions, 4 deletions
diff --git a/activerecord/test/cases/enum_test.rb b/activerecord/test/cases/enum_test.rb
index 35e8a98156..1b95708cb3 100644
--- a/activerecord/test/cases/enum_test.rb
+++ b/activerecord/test/cases/enum_test.rb
@@ -16,7 +16,7 @@ class EnumTest < ActiveRecord::TestCase
     assert @book.unread?
   end
 
-  test "query state with symbol" do
+  test "query state with strings" do
     assert_equal "proposed", @book.status
     assert_equal "unread", @book.read_status
   end
@@ -51,6 +51,77 @@ class EnumTest < ActiveRecord::TestCase
     assert @book.written?
   end
 
+  test "enum changed attributes" do
+    old_status = @book.status
+    @book.status = :published
+    assert_equal old_status, @book.changed_attributes[:status]
+  end
+
+  test "enum changes" do
+    old_status = @book.status
+    @book.status = :published
+    assert_equal [old_status, 'published'], @book.changes[:status]
+  end
+
+  test "enum attribute was" do
+    old_status = @book.status
+    @book.status = :published
+    assert_equal old_status, @book.attribute_was(:status)
+  end
+
+  test "enum attribute changed" do
+    @book.status = :published
+    assert @book.attribute_changed?(:status)
+  end
+
+  test "enum attribute changed to" do
+    @book.status = :published
+    assert @book.attribute_changed?(:status, to: 'published')
+  end
+
+  test "enum attribute changed from" do
+    old_status = @book.status
+    @book.status = :published
+    assert @book.attribute_changed?(:status, from: old_status)
+  end
+
+  test "enum attribute changed from old status to new status" do
+    old_status = @book.status
+    @book.status = :published
+    assert @book.attribute_changed?(:status, from: old_status, to: 'published')
+  end
+
+  test "enum didn't change" do
+    old_status = @book.status
+    @book.status = old_status
+    assert_not @book.attribute_changed?(:status)
+  end
+
+  test "persist changes that are dirty" do
+    @book.status = :published
+    assert @book.attribute_changed?(:status)
+    @book.status = :written
+    assert @book.attribute_changed?(:status)
+  end
+
+  test "reverted changes that are not dirty" do
+    old_status = @book.status
+    @book.status = :published
+    assert @book.attribute_changed?(:status)
+    @book.status = old_status
+    assert_not @book.attribute_changed?(:status)
+  end
+
+  test "reverted changes are not dirty going from nil to value and back" do
+    book = Book.create!(nullable_status: nil)
+
+    book.nullable_status = :married
+    assert book.attribute_changed?(:nullable_status)
+
+    book.nullable_status = nil
+    assert_not book.attribute_changed?(:nullable_status)
+  end
+
   test "assign non existing value raises an error" do
     e = assert_raises(ArgumentError) do
       @book.status = :unknown
@@ -58,9 +129,97 @@ class EnumTest < ActiveRecord::TestCase
     assert_equal "'unknown' is not a valid status", e.message
   end
 
+  test "assign nil value" do
+    @book.status = nil
+    assert @book.status.nil?
+  end
+
+  test "assign empty string value" do
+    @book.status = ''
+    assert @book.status.nil?
+  end
+
+  test "assign long empty string value" do
+    @book.status = '   '
+    assert @book.status.nil?
+  end
+
   test "constant to access the mapping" do
-    assert_equal 0, Book::STATUS[:proposed]
-    assert_equal 1, Book::STATUS["written"]
-    assert_equal 2, Book::STATUS[:published]
+    assert_equal 0, Book.statuses[:proposed]
+    assert_equal 1, Book.statuses["written"]
+    assert_equal 2, Book.statuses[:published]
+  end
+
+  test "building new objects with enum scopes" do
+    assert Book.written.build.written?
+    assert Book.read.build.read?
+  end
+
+  test "creating new objects with enum scopes" do
+    assert Book.written.create.written?
+    assert Book.read.create.read?
+  end
+
+  test "_before_type_cast returns the enum label (required for form fields)" do
+    assert_equal "proposed", @book.status_before_type_cast
+  end
+
+  test "reserved enum names" do
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = "books"
+      enum status: [:proposed, :written, :published]
+    end
+
+    conflicts = [
+      :column,     # generates class method .columns, which conflicts with an AR method
+      :logger,     # generates #logger, which conflicts with an AR method
+      :attributes, # generates #attributes=, which conflicts with an AR method
+    ]
+
+    conflicts.each_with_index do |name, i|
+      assert_raises(ArgumentError, "enum name `#{name}` should not be allowed") do
+        klass.class_eval { enum name => ["value_#{i}"] }
+      end
+    end
+  end
+
+  test "reserved enum values" do
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = "books"
+      enum status: [:proposed, :written, :published]
+    end
+
+    conflicts = [
+      :new,      # generates a scope that conflicts with an AR class method
+      :valid,    # generates #valid?, which conflicts with an AR method
+      :save,     # generates #save!, which conflicts with an AR method
+      :proposed, # same value as an existing enum
+    ]
+
+    conflicts.each_with_index do |value, i|
+      assert_raises(ArgumentError, "enum value `#{value}` should not be allowed") do
+        klass.class_eval { enum "status_#{i}" => [value] }
+      end
+    end
+  end
+
+  test "overriding enum method should not raise" do
+    assert_nothing_raised do
+      Class.new(ActiveRecord::Base) do
+        self.table_name = "books"
+
+        def published!
+          super
+          "do publish work..."
+        end
+
+        enum status: [:proposed, :written, :published]
+
+        def written!
+          super
+          "do written work..."
+        end
+      end
+    end
   end
 end