Move Attribute and AttributeSet to ActiveModel

Use these to back the attributes API.  Stop automatically including
ActiveModel::Dirty in ActiveModel::Attributes, and make it optional.

1 files changed, 255 insertions, 0 deletions

diff --git a/activemodel/test/cases/attribute_set_test.rb b/activemodel/test/cases/attribute_set_test.rb
new file mode 100644
index 0000000000..d50e6cfa7a
--- /dev/null
+++ b/activemodel/test/cases/attribute_set_test.rb
@@ -0,0 +1,255 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveModel
+  class AttributeSetTest < ActiveModel::TestCase
+    test "building a new set from raw attributes" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
+      attributes = builder.build_from_database(foo: "1.1", bar: "2.2")
+
+      assert_equal 1, attributes[:foo].value
+      assert_equal 2.2, attributes[:bar].value
+      assert_equal :foo, attributes[:foo].name
+      assert_equal :bar, attributes[:bar].name
+    end
+
+    test "building with custom types" do
+      builder = AttributeSet::Builder.new(foo: Type::Float.new)
+      attributes = builder.build_from_database({ foo: "3.3", bar: "4.4" }, { bar: Type::Integer.new })
+
+      assert_equal 3.3, attributes[:foo].value
+      assert_equal 4, attributes[:bar].value
+    end
+
+    test "[] returns a null object" do
+      builder = AttributeSet::Builder.new(foo: Type::Float.new)
+      attributes = builder.build_from_database(foo: "3.3")
+
+      assert_equal "3.3", attributes[:foo].value_before_type_cast
+      assert_nil attributes[:bar].value_before_type_cast
+      assert_equal :bar, attributes[:bar].name
+    end
+
+    test "duping creates a new hash, but does not dup the attributes" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::String.new)
+      attributes = builder.build_from_database(foo: 1, bar: "foo")
+
+      # Ensure the type cast value is cached
+      attributes[:foo].value
+      attributes[:bar].value
+
+      duped = attributes.dup
+      duped.write_from_database(:foo, 2)
+      duped[:bar].value << "bar"
+
+      assert_equal 1, attributes[:foo].value
+      assert_equal 2, duped[:foo].value
+      assert_equal "foobar", attributes[:bar].value
+      assert_equal "foobar", duped[:bar].value
+    end
+
+    test "deep_duping creates a new hash and dups each attribute" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::String.new)
+      attributes = builder.build_from_database(foo: 1, bar: "foo")
+
+      # Ensure the type cast value is cached
+      attributes[:foo].value
+      attributes[:bar].value
+
+      duped = attributes.deep_dup
+      duped.write_from_database(:foo, 2)
+      duped[:bar].value << "bar"
+
+      assert_equal 1, attributes[:foo].value
+      assert_equal 2, duped[:foo].value
+      assert_equal "foo", attributes[:bar].value
+      assert_equal "foobar", duped[:bar].value
+    end
+
+    test "freezing cloned set does not freeze original" do
+      attributes = AttributeSet.new({})
+      clone = attributes.clone
+
+      clone.freeze
+
+      assert clone.frozen?
+      assert_not attributes.frozen?
+    end
+
+    test "to_hash returns a hash of the type cast values" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
+      attributes = builder.build_from_database(foo: "1.1", bar: "2.2")
+
+      assert_equal({ foo: 1, bar: 2.2 }, attributes.to_hash)
+      assert_equal({ foo: 1, bar: 2.2 }, attributes.to_h)
+    end
+
+    test "to_hash maintains order" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
+      attributes = builder.build_from_database(foo: "2.2", bar: "3.3")
+
+      attributes[:bar]
+      hash = attributes.to_h
+
+      assert_equal [[:foo, 2], [:bar, 3.3]], hash.to_a
+    end
+
+    test "values_before_type_cast" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Integer.new)
+      attributes = builder.build_from_database(foo: "1.1", bar: "2.2")
+
+      assert_equal({ foo: "1.1", bar: "2.2" }, attributes.values_before_type_cast)
+    end
+
+    test "known columns are built with uninitialized attributes" do
+      attributes = attributes_with_uninitialized_key
+      assert attributes[:foo].initialized?
+      assert_not attributes[:bar].initialized?
+    end
+
+    test "uninitialized attributes are not included in the attributes hash" do
+      attributes = attributes_with_uninitialized_key
+      assert_equal({ foo: 1 }, attributes.to_hash)
+    end
+
+    test "uninitialized attributes are not included in keys" do
+      attributes = attributes_with_uninitialized_key
+      assert_equal [:foo], attributes.keys
+    end
+
+    test "uninitialized attributes return false for key?" do
+      attributes = attributes_with_uninitialized_key
+      assert attributes.key?(:foo)
+      assert_not attributes.key?(:bar)
+    end
+
+    test "unknown attributes return false for key?" do
+      attributes = attributes_with_uninitialized_key
+      assert_not attributes.key?(:wibble)
+    end
+
+    test "fetch_value returns the value for the given initialized attribute" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
+      attributes = builder.build_from_database(foo: "1.1", bar: "2.2")
+
+      assert_equal 1, attributes.fetch_value(:foo)
+      assert_equal 2.2, attributes.fetch_value(:bar)
+    end
+
+    test "fetch_value returns nil for unknown attributes" do
+      attributes = attributes_with_uninitialized_key
+      assert_nil attributes.fetch_value(:wibble) { "hello" }
+    end
+
+    test "fetch_value returns nil for unknown attributes when types has a default" do
+      types = Hash.new(Type::Value.new)
+      builder = AttributeSet::Builder.new(types)
+      attributes = builder.build_from_database
+
+      assert_nil attributes.fetch_value(:wibble) { "hello" }
+    end
+
+    test "fetch_value uses the given block for uninitialized attributes" do
+      attributes = attributes_with_uninitialized_key
+      value = attributes.fetch_value(:bar) { |n| n.to_s + "!" }
+      assert_equal "bar!", value
+    end
+
+    test "fetch_value returns nil for uninitialized attributes if no block is given" do
+      attributes = attributes_with_uninitialized_key
+      assert_nil attributes.fetch_value(:bar)
+    end
+
+    test "the primary_key is always initialized" do
+      builder = AttributeSet::Builder.new({ foo: Type::Integer.new }, :foo)
+      attributes = builder.build_from_database
+
+      assert attributes.key?(:foo)
+      assert_equal [:foo], attributes.keys
+      assert attributes[:foo].initialized?
+    end
+
+    class MyType
+      def cast(value)
+        return if value.nil?
+        value + " from user"
+      end
+
+      def deserialize(value)
+        return if value.nil?
+        value + " from database"
+      end
+
+      def assert_valid_value(*)
+      end
+    end
+
+    test "write_from_database sets the attribute with database typecasting" do
+      builder = AttributeSet::Builder.new(foo: MyType.new)
+      attributes = builder.build_from_database
+
+      assert_nil attributes.fetch_value(:foo)
+
+      attributes.write_from_database(:foo, "value")
+
+      assert_equal "value from database", attributes.fetch_value(:foo)
+    end
+
+    test "write_from_user sets the attribute with user typecasting" do
+      builder = AttributeSet::Builder.new(foo: MyType.new)
+      attributes = builder.build_from_database
+
+      assert_nil attributes.fetch_value(:foo)
+
+      attributes.write_from_user(:foo, "value")
+
+      assert_equal "value from user", attributes.fetch_value(:foo)
+    end
+
+    def attributes_with_uninitialized_key
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Float.new)
+      builder.build_from_database(foo: "1.1")
+    end
+
+    test "freezing doesn't prevent the set from materializing" do
+      builder = AttributeSet::Builder.new(foo: Type::String.new)
+      attributes = builder.build_from_database(foo: "1")
+
+      attributes.freeze
+      assert_equal({ foo: "1" }, attributes.to_hash)
+    end
+
+    test "#accessed_attributes returns only attributes which have been read" do
+      builder = AttributeSet::Builder.new(foo: Type::Value.new, bar: Type::Value.new)
+      attributes = builder.build_from_database(foo: "1", bar: "2")
+
+      assert_equal [], attributes.accessed
+
+      attributes.fetch_value(:foo)
+
+      assert_equal [:foo], attributes.accessed
+    end
+
+    test "#map returns a new attribute set with the changes applied" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Integer.new)
+      attributes = builder.build_from_database(foo: "1", bar: "2")
+      new_attributes = attributes.map do |attr|
+        attr.with_cast_value(attr.value + 1)
+      end
+
+      assert_equal 2, new_attributes.fetch_value(:foo)
+      assert_equal 3, new_attributes.fetch_value(:bar)
+    end
+
+    test "comparison for equality is correctly implemented" do
+      builder = AttributeSet::Builder.new(foo: Type::Integer.new, bar: Type::Integer.new)
+      attributes = builder.build_from_database(foo: "1", bar: "2")
+      attributes2 = builder.build_from_database(foo: "1", bar: "2")
+      attributes3 = builder.build_from_database(foo: "2", bar: "2")
+
+      assert_equal attributes, attributes2
+      assert_not_equal attributes2, attributes3
+    end
+  end
+end