# frozen_string_literal: true require "cases/helper" module ActiveModel class AttributeTest < ActiveSupport::TestCase setup do @type = Minitest::Mock.new end teardown do assert @type.verify end test "from_database + read type casts from database" do @type.expect(:deserialize, "type cast from database", ["a value"]) attribute = Attribute.from_database(nil, "a value", @type) type_cast_value = attribute.value assert_equal "type cast from database", type_cast_value end test "from_user + read type casts from user" do @type.expect(:cast, "type cast from user", ["a value"]) attribute = Attribute.from_user(nil, "a value", @type) type_cast_value = attribute.value assert_equal "type cast from user", type_cast_value end test "reading memoizes the value" do @type.expect(:deserialize, "from the database", ["whatever"]) attribute = Attribute.from_database(nil, "whatever", @type) type_cast_value = attribute.value second_read = attribute.value assert_equal "from the database", type_cast_value assert_same type_cast_value, second_read end test "reading memoizes falsy values" do @type.expect(:deserialize, false, ["whatever"]) attribute = Attribute.from_database(nil, "whatever", @type) attribute.value attribute.value end test "read_before_typecast returns the given value" do attribute = Attribute.from_database(nil, "raw value", @type) raw_value = attribute.value_before_type_cast assert_equal "raw value", raw_value end test "from_database + read_for_database type casts to and from database" do @type.expect(:deserialize, "read from database", ["whatever"]) @type.expect(:serialize, "ready for database", ["read from database"]) attribute = Attribute.from_database(nil, "whatever", @type) serialize = attribute.value_for_database assert_equal "ready for database", serialize end test "from_user + read_for_database type casts from the user to the database" do @type.expect(:cast, "read from user", ["whatever"]) @type.expect(:serialize, "ready for database", ["read from user"]) attribute = Attribute.from_user(nil, "whatever", @type) serialize = attribute.value_for_database assert_equal "ready for database", serialize end test "duping dups the value" do @type.expect(:deserialize, +"type cast", ["a value"]) attribute = Attribute.from_database(nil, "a value", @type) value_from_orig = attribute.value value_from_clone = attribute.dup.value value_from_orig << " foo" assert_equal "type cast foo", value_from_orig assert_equal "type cast", value_from_clone end test "duping does not dup the value if it is not dupable" do @type.expect(:deserialize, false, ["a value"]) attribute = Attribute.from_database(nil, "a value", @type) assert_same attribute.value, attribute.dup.value end test "duping does not eagerly type cast if we have not yet type cast" do attribute = Attribute.from_database(nil, "a value", @type) attribute.dup end class MyType def cast(value) value + " from user" end def deserialize(value) value + " from database" end def assert_valid_value(*) end end test "with_value_from_user returns a new attribute with the value from the user" do old = Attribute.from_database(nil, "old", MyType.new) new = old.with_value_from_user("new") assert_equal "old from database", old.value assert_equal "new from user", new.value end test "with_value_from_database returns a new attribute with the value from the database" do old = Attribute.from_user(nil, "old", MyType.new) new = old.with_value_from_database("new") assert_equal "old from user", old.value assert_equal "new from database", new.value end test "uninitialized attributes yield their name if a block is given to value" do block = proc { |name| name.to_s + "!" } foo = Attribute.uninitialized(:foo, nil) bar = Attribute.uninitialized(:bar, nil) assert_equal "foo!", foo.value(&block) assert_equal "bar!", bar.value(&block) end test "uninitialized attributes have no value" do assert_nil Attribute.uninitialized(:foo, nil).value end test "attributes equal other attributes with the same constructor arguments" do first = Attribute.from_database(:foo, 1, Type::Integer.new) second = Attribute.from_database(:foo, 1, Type::Integer.new) assert_equal first, second end test "attributes do not equal attributes with different names" do first = Attribute.from_database(:foo, 1, Type::Integer.new) second = Attribute.from_database(:bar, 1, Type::Integer.new) assert_not_equal first, second end test "attributes do not equal attributes with different types" do first = Attribute.from_database(:foo, 1, Type::Integer.new) second = Attribute.from_database(:foo, 1, Type::Float.new) assert_not_equal first, second end test "attributes do not equal attributes with different values" do first = Attribute.from_database(:foo, 1, Type::Integer.new) second = Attribute.from_database(:foo, 2, Type::Integer.new) assert_not_equal first, second end test "attributes do not equal attributes of other classes" do first = Attribute.from_database(:foo, 1, Type::Integer.new) second = Attribute.from_user(:foo, 1, Type::Integer.new) assert_not_equal first, second end test "an attribute has not been read by default" do attribute = Attribute.from_database(:foo, 1, Type::Value.new) assert_not_predicate attribute, :has_been_read? end test "an attribute has been read when its value is calculated" do attribute = Attribute.from_database(:foo, 1, Type::Value.new) attribute.value assert_predicate attribute, :has_been_read? end test "an attribute is not changed if it hasn't been assigned or mutated" do attribute = Attribute.from_database(:foo, 1, Type::Value.new) assert_not_predicate attribute, :changed? end test "an attribute is changed if it's been assigned a new value" do attribute = Attribute.from_database(:foo, 1, Type::Value.new) changed = attribute.with_value_from_user(2) assert_predicate changed, :changed? end test "an attribute is not changed if it's assigned the same value" do attribute = Attribute.from_database(:foo, 1, Type::Value.new) unchanged = attribute.with_value_from_user(1) assert_not_predicate unchanged, :changed? end test "an attribute cannot be mutated if it has not been read, and skips expensive calculations" do type_which_raises_from_all_methods = Object.new attribute = Attribute.from_database(:foo, "bar", type_which_raises_from_all_methods) assert_not_predicate attribute, :changed_in_place? end test "an attribute is changed if it has been mutated" do attribute = Attribute.from_database(:foo, "bar", Type::String.new) attribute.value << "!" assert_predicate attribute, :changed_in_place? assert_predicate attribute, :changed? end test "an attribute can forget its changes" do attribute = Attribute.from_database(:foo, "bar", Type::String.new) changed = attribute.with_value_from_user("foo") forgotten = changed.forgetting_assignment assert changed.changed? # sanity check assert_not_predicate forgotten, :changed? end test "with_value_from_user validates the value" do type = Type::Value.new type.define_singleton_method(:assert_valid_value) do |value| if value == 1 raise ArgumentError end end attribute = Attribute.from_database(:foo, 1, type) assert_equal 1, attribute.value assert_equal 2, attribute.with_value_from_user(2).value assert_raises ArgumentError do attribute.with_value_from_user(1) end end test "with_type preserves mutations" do attribute = Attribute.from_database(:foo, +"", Type::Value.new) attribute.value << "1" assert_equal 1, attribute.with_type(Type::Integer.new).value end end end