cpp-json/test/json_binder_polymorphic.t.h

//
//  json_binder_polymorphic.t.h
//  json
//
//  Created by Sam Jaffe on 11/14/18.
//  Copyright © 2018 Sam Jaffe. All rights reserved.
//

#pragma once

#include <cxxtest/TestSuite.h>
#include "json/json_binder.hpp"

struct Base {
  virtual ~Base() = default;
  virtual void run() const = 0;
};

struct Left : public Base {
  int a;
  void run() const override {}
};

struct Right : public Base {
  std::string a;
  void run() const override {}
};

bool operator==(Left const & lhs, Left const & rhs) {
  return lhs.a == rhs.a;
}

bool operator==(Right const & lhs, Right const & rhs) {
  return lhs.a == rhs.a;
}

using namespace json;
using namespace json::binder;
object_binder<Left> GetLeftBinder() {
  return object_binder<Left>()
  ("a", &Left::a);
}

object_binder<Right> GetRightBinder() {
  return object_binder<Right>()
  ("a", &Right::a);
}

using pBase = std::unique_ptr<Base>;

polymorphic_binder<pBase> GetBinder() {
  return polymorphic_binder<pBase>()
  ("Left", GetLeftBinder())
  ("Right", GetRightBinder());
}

polymorphic_binder<pBase> & Get() {
  static polymorphic_binder<pBase> _ = GetBinder();
  return _;
}

using namespace json::parser;
class json_binder_polymorphic_TestSuite : public CxxTest::TestSuite {
  public:
  void testCanHitLeftPolymorph() {
    char data[] = "{\"@id\":\"Left\", \"@value\":{\"a\":1}}";
    pBase out;
    Left expected; expected.a = 1;
    TS_ASSERT_THROWS_NOTHING(parse(json::binder::bind(out, Get()), data));
    TS_ASSERT_DIFFERS(&*out, nullptr);
    TS_ASSERT(dynamic_cast<Left*>(&*out));
    TS_ASSERT_EQUALS(dynamic_cast<Left&>(*out), expected);
  }

  void testCanHitRightPolymorph() {
    char data[] = "{\"@id\":\"Right\", \"@value\":{\"a\":\"hello\"}}";
    pBase out;
    Right expected; expected.a = "hello";
    TS_ASSERT_THROWS_NOTHING(parse(json::binder::bind(out, Get()), data));
    TS_ASSERT_DIFFERS(&*out, nullptr);
    TS_ASSERT(dynamic_cast<Right*>(&*out));
    TS_ASSERT_EQUALS(dynamic_cast<Right&>(*out), expected);
  }
};