cpp-json/test/json_binder_value_double_test.cxx

//
//  json_binder_value_double.t.h
//  json
//
//  Created by Sam Jaffe on 2/25/17.
//

#include "json/json_binder.hpp"
#include <gmock/gmock.h>

using namespace json::binder;
using namespace json::parser;
using namespace ::testing;

TEST(JsonBinderDoubleTest, ParsesDouble) {
  char data[] = "0.5";
  double out = 0.0;
  value_binder<double> binder{};
  parse(bind(out, binder), data, allow_all);
  EXPECT_THAT(out, 0.5);
}

TEST(JsonBinderDoubleTest, ParsesScientific) {
  char data[] = "2e4";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_NO_THROW(parse(bind(out, binder), data, allow_all));
}

TEST(JsonBinderDoubleTest, ThrowsOnEOB) {
  char data[] = "";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_THROW(parse(bind(out, binder), data, allow_all),
               json::json_numeric_exception);
}

TEST(JsonBinderDoubleTest, ThrowsOnNaN) {
  char data[] = "one half";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_THROW(parse(bind(out, binder), data, allow_all),
               json::json_numeric_exception);
}

TEST(JsonBinderDoubleTest, ThrowsOnTokenConcat) {
  char data[] = "5.0boo";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_THROW(parse(bind(out, binder), data, disable_concatenated_json_bodies),
               json::malformed_json_exception);
  EXPECT_THAT(out, 5.0);
}

TEST(JsonBinderDoubleTest, OutputIsEssentiallyEqualDblMax) {
  char data[] = "1.79769e+308";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_NO_THROW(parse(bind(out, binder), data, allow_all));
  EXPECT_THAT(out, DoubleNear(std::numeric_limits<double>::max(), 1E303));
}

TEST(JsonBinderDoubleTest, ThrowsOnOOBMax) {
  char data[] = "1.8e+308";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_THROW(parse(bind(out, binder), data, allow_all),
               json::json_numeric_width_exception);
}

TEST(JsonBinderDoubleTest, OutputIsEssentiallyEqualDblLowest) {
  char data[] = "-1.79769e+308";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_NO_THROW(parse(bind(out, binder), data, allow_all));
  EXPECT_THAT(out, DoubleNear(std::numeric_limits<double>::lowest(), 1E303));
}

TEST(JsonBinderDoubleTest, ThrowsOnOOBLowest) {
  char data[] = "-1.8e+308";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_THROW(parse(bind(out, binder), data, allow_all),
               json::json_numeric_width_exception);
}

TEST(JsonBinderDoubleTest, OutputIsEssentiallyEqualDblMin) {
  char data[] = "2.22508e-308"; // 2.22507e-308 is min according to cppreference
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_NO_THROW(parse(bind(out, binder), data, allow_all));
  EXPECT_THAT(out, DoubleNear(std::numeric_limits<double>::min(), 1E-303));
}

TEST(JsonBinderDoubleTest, ThrowsOnOOBMin) {
  char data[] = "2e-308";
  double out = 0.0;
  value_binder<double> binder{};
  EXPECT_THROW(parse(bind(out, binder), data, allow_all),
               json::json_numeric_width_exception);
}

TEST(JsonBinderDoubleTest, ParseNoLossWithExactRep) {
  std::stringstream ss;
  double in = 500., out = 0;
  value_binder<double> binder{};
  write(bind(in, binder), ss);
  parse(bind(out, binder), ss.str().c_str(), allow_all);
  EXPECT_THAT(out, in);
}

TEST(JsonBinderDoubleTest, ParseNoLossWithInexactRep) {
  std::stringstream ss;
  double in = 0.3, out = 0;
  value_binder<double> binder{};
  write(bind(in, binder), ss);
  parse(bind(out, binder), ss.str().c_str(), allow_all);
  EXPECT_THAT(out, in);
}

TEST(JsonBinderDoubleTest, ParseNoLossWithLargeNumberSci) {
  std::stringstream ss;
  double in = 1.34e300, out = 0.0;
  value_binder<double> binder{};
  write(bind(in, binder), ss);
  parse(bind(out, binder), ss.str().c_str(), allow_all);
  EXPECT_THAT(out, in);
}

TEST(JsonBinderDoubleTest, ParseNoLossWithLargeNegativeNumberSci) {
  std::stringstream ss;
  double in = 1.34e-300, out = 0.0;
  value_binder<double> binder{};
  write(bind(in, binder), ss);
  parse(bind(out, binder), ss.str().c_str(), allow_all);
  EXPECT_THAT(out, DoubleNear(in, 1e-299));
}

TEST(JsonBinderDoubleTest, ParseNoLossWithLargeNumber) {
  std::stringstream ss;
  double in = 52450012.25, out = 0.0;
  value_binder<double> binder{};
  write(bind(in, binder), ss);
  parse(bind(out, binder), ss.str().c_str(), allow_all);
  EXPECT_THAT(out, in);
}

TEST(JsonBinderDoubleTest, ParseEssentiallyEqualAtSeveralDecimalPlaces) {
  std::stringstream ss;
  double in = 0.0002517867, out = 0.0;
  value_binder<double> binder{};
  write(bind(in, binder), ss);
  EXPECT_NO_THROW(parse(bind(out, binder), ss.str().c_str(), allow_all));
  EXPECT_THAT(out, DoubleNear(in, 0.000001));
}