mariadb-columnstore-engine/tests/patterns_test.cpp

#include <mpark/patterns.hpp>

#include <string>
#include <utility>
#include <vector>

#include <gtest/gtest.h>

struct Aggregate
{
  double d;
  std::string s;
  std::vector<int> v;
};

TEST(Aggregate, LRef)
{
  Aggregate aggregate{4.2, "hello", {101, 202}};

  using namespace mpark::patterns;
  double& result = match(aggregate)(
      pattern(ds(arg, "world", _)) = [](double& d) -> double& { return d; },
      pattern(ds(arg, "hello", _)) = [](double& d) -> double& { return d; });

  EXPECT_EQ(aggregate.d, result);
  EXPECT_EQ(&aggregate.d, &result);
}

TEST(Aggregate, ConstLRef)
{
  const Aggregate aggregate{4.2, "hello", {101, 202}};

  using namespace mpark::patterns;
  const double& result = match(aggregate)(
      pattern(ds(arg, "world", _)) = [](const double& d) -> const double& { return d; },
      pattern(ds(arg, "hello", _)) = [](const double& d) -> const double& { return d; });

  EXPECT_EQ(aggregate.d, result);
  EXPECT_EQ(&aggregate.d, &result);
}

TEST(Aggregate, RRef)
{
  auto aggregate = [] { return Aggregate{4.2, "hello", {101, 202}}; };

  using namespace mpark::patterns;
  double result = match(aggregate())(
      pattern(ds(arg, "world", _)) = [](double&& d) -> double { return std::move(d); },
      pattern(ds(arg, "hello", _)) = [](double&& d) -> double { return std::move(d); });

  EXPECT_EQ(4.2, result);
}

TEST(Aggregate, Empty)
{
  struct
  {
  } empty;

  using namespace mpark::patterns;
  match(empty)(pattern(ds()) = [] {});
}

TEST(Aggregate, OneChar)
{
  struct
  {
    char x;
  } one{'x'};

  using namespace mpark::patterns;
  int result = match(one)(
      pattern(ds('a')) = [] { return false; }, pattern(ds('x')) = [] { return true; });

  EXPECT_TRUE(result);
}

TEST(Aggregate, OneInt)
{
  struct
  {
    int x;
  } one{101};

  using namespace mpark::patterns;
  int result = match(one)(
      pattern(ds(101)) = [] { return true; }, pattern(ds(1)) = [] { return false; });

  EXPECT_TRUE(result);
}

TEST(Aggregate, TwoChars)
{
  struct
  {
    char x;
    char y;
  } two{'x', 'y'};

  using namespace mpark::patterns;
  bool result = match(two)(
      pattern(ds('a', 'b')) = [] { return false; }, pattern(ds('x', 'y')) = [] { return true; });

  EXPECT_TRUE(result);
}

TEST(Aggregate, TwoInts)
{
  struct
  {
    int x;
    int y;
  } two{101, 202};

  using namespace mpark::patterns;
  bool result = match(two)(
      pattern(ds(1, 2)) = [] { return false; }, pattern(ds(101, 202)) = [] { return true; });

  EXPECT_TRUE(result);
}

TEST(Aggregate, ThreeChars)
{
  struct
  {
    char x;
    char y;
    char z;
  } three{'x', 'y', 'z'};

  using namespace mpark::patterns;
  bool result = match(three)(
      pattern(ds('x', 'y', 'z')) = [] { return true; }, pattern(ds('a', 'b', 'c')) = [] { return false; });

  EXPECT_TRUE(result);
}

TEST(Aggregate, FourChars)
{
  struct
  {
    char a;
    char b;
    char c;
    char d;
  } four{'a', 'b', 'c', 'd'};

  using namespace mpark::patterns;
  bool result = match(four)(
      pattern(ds('p', 'q', 'r', 's')) = [] { return false; },
      pattern(ds('a', 'b', 'c', 'd')) = [] { return true; });

  EXPECT_TRUE(result);
}