feat: Added option library (#58)

Author: ellistarn

option/function.go

@@ -0,0 +1,13 @@
+package option
+
+type Function[T any] func(*T)
+
+func Resolve[T any](opts ...Function[T]) *T {
+	o := new(T)
+	for _, opt := range opts {
+		if opt != nil {
+			opt(o)
+		}
+	}
+	return o
+}

option/function_test.go

@@ -0,0 +1,50 @@
+package option_test
+
+import (
+	options "github.com/awslabs/operatorpkg/option"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+type Option struct {
+	Foo bool
+	Bar string
+	Baz int
+}
+
+func FooOptions(o *Option) {
+	o.Foo = true
+}
+func BarOptions(o *Option) {
+	o.Bar = "bar"
+}
+
+func BazOptions(baz int) options.Function[Option] {
+	return func(o *Option) {
+		o.Baz = baz
+	}
+}
+
+var _ = Describe("Function", func() {
+	It("should resolve options", func() {
+		Expect(options.Resolve(
+			FooOptions,
+			BarOptions,
+			BazOptions(5),
+		)).To(Equal(&Option{
+			Foo: true,
+			Bar: "bar",
+			Baz: 5,
+		}))
+
+		Expect(options.Resolve(
+			FooOptions,
+			BarOptions,
+		)).To(Equal(&Option{
+			Foo: true,
+			Bar: "bar",
+		}))
+
+		Expect(options.Resolve[Option]()).To(Equal(&Option{}))
+	})
+})

option/suite_test.go

@@ -0,0 +1,13 @@
+package option_test
+
+import (
+	"testing"
+
+	"github.com/onsi/ginkgo/v2"
+	"github.com/onsi/gomega"
+)
+
+func Test(t *testing.T) {
+	gomega.RegisterFailHandler(ginkgo.Fail)
+	ginkgo.RunSpecs(t, "Options")
+}