factory

func ChainableModifier ¶

func ChainableModifier[T any](initFactory func() T) func(modifiers ...func(T)) T

ChainableModifier creates a factory that produces an initial value from initFactory, then lets you change modifiers to modify that value. You're then returned the value once all modifiers have ran over it. This can be particularly useful when building mock data in tests.

func example() {
	chain := ChainableModifier(func() *pb.MyRequest {
		return &pb.MyRequest{Foo: true, Bar: false}
	})

	firstRequest := chain() // returns &pb.MyRequest{Foo: true, Bar: false}

	secondRequestWithBarTrue := chain(func(v *pb.MyRequest) {
		v.Bar = true
	}) // returns &pb.MyRequest{Foo: true, Bar: true}

	thirdRequestWithValuesSwapped := chain(func(v *pb.MyRequest) {
		v.Foo = false
	}, func(v *pb.MyRequest) {
		v.Bar = true
	}) // returns &pb.MyRequest{Foo: false, Bar: true}
}