Go: checkJSONRoundtrip

jsonroundtrip_test.go

package main_test

import (
    "encoding/json"
    "reflect"
)

func checkJSONRoundtrip(t *testing.T, value interface{}, expectedJSON json.RawMessage) bool {
	b, err := json.Marshal(value)
	if err != nil {
		t.Errorf("%v marshal JSON: %v", value, err)
		return false
	}
	if !bytes.Equal(b, []byte(expectedJSON)) {
		var i1, i2 interface{}
		e1 := json.Unmarshal(b, &i1)
		e2 := json.Unmarshal(expectedJSON, &i2)
		if e1 != nil {
			t.Fatal(e1)
		}
		if e2 != nil {
			t.Fatal(e2)
		}
		if !reflect.DeepEqual(i1, i2) {
			t.Errorf("%v marshal JSON: mismatch (got %s, expecting %s)", value, b, []byte(expectedJSON))
			return false
		}
	}

	target := reflect.New(reflect.TypeOf(value))
	err = json.Unmarshal(b, target.Interface())
	if !reflect.DeepEqual(target.Elem().Interface(), value) {
		t.Errorf("%v unmarshal JSON: got %v", value, target.Elem().Interface())
		return false
	}
	return true
}