json_test.go

package goption

import (
	"encoding/json"
	"testing"
)

type Bar struct {
	Baz string
}

type Foo struct {
	Stuff  Option[Bar]
	Things []int
}

func TestJSONMarshal(t *testing.T) {
	foo := Foo{
		Things: []int{1, 2, 3},
	}
	encoded, err := json.Marshal(foo)
	if err != nil {
		t.Fatalf("Failed marshalling json: %s", err)
	}

	if string(encoded) != `{"Stuff":null,"Things":[1,2,3]}` {
		t.Errorf("Unexpected encoded data: %s", string(encoded))
	}

	foo.Stuff = Some(Bar{Baz: "hey!"})
	encoded, err = json.Marshal(foo)
	if err != nil {
		t.Fatalf("Failed marshalling json: %s", err)
	}

	if string(encoded) != `{"Stuff":{"Baz":"hey!"},"Things":[1,2,3]}` {
		t.Errorf("Unexpected encoded data: %s", string(encoded))
	}
}

func TestJSONUnmarshal(t *testing.T) {
	var foo Foo
	if err := json.Unmarshal([]byte(`{"Stuff":null,"Things":[1,2,3]}`), &foo); err != nil {
		t.Errorf("Failed unmarshalling into foo: %s", err)
	} else if len(foo.Things) != 3 || foo.Things[0] != 1 || foo.Things[1] != 2 || foo.Things[2] != 3 {
		t.Errorf("Failed unmarshalling foo.Things: %v", foo.Things)
	} else if foo.Stuff.Ok() {
		t.Errorf("Expected optional value to be empty.")
	}

	if err := json.Unmarshal([]byte(`{"Stuff":{"Baz":"hey!"},"Things":[1,2,3]}`), &foo); err != nil {
		t.Errorf("Failed unmarshalling into foo: %s", err)
	} else if len(foo.Things) != 3 || foo.Things[0] != 1 || foo.Things[1] != 2 || foo.Things[2] != 3 {
		t.Errorf("Failed unmarshalling foo.Things: %v", foo.Things)
	} else if !foo.Stuff.Ok() || foo.Stuff.Unwrap().Baz != "hey!" {
		t.Errorf("Expected optional value to be present.")
	}
}