blob: 42917e0ffc4e411973a6a3ed2eb1333342f14154 [file] [log] [blame]
// Copyright 2017 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/base/template-utils.h"
#include "test/unittests/test-utils.h"
namespace v8 {
namespace base {
namespace template_utils_unittest {
////////////////////////////
// Test make_array.
////////////////////////////
namespace {
template <typename T, size_t Size>
void CheckArrayEquals(const std::array<T, Size>& arr1,
const std::array<T, Size>& arr2) {
for (size_t i = 0; i < Size; ++i) {
CHECK_EQ(arr1[i], arr2[i]);
}
}
} // namespace
TEST(TemplateUtilsTest, MakeArraySimple) {
auto computed_array = base::make_array<3>([](int i) { return 1 + (i * 3); });
std::array<int, 3> expected{{1, 4, 7}};
CheckArrayEquals(computed_array, expected);
}
namespace {
constexpr int doubleIntValue(int i) { return i * 2; }
}; // namespace
TEST(TemplateUtilsTest, MakeArrayConstexpr) {
constexpr auto computed_array = base::make_array<3>(doubleIntValue);
constexpr std::array<int, 3> expected{{0, 2, 4}};
CheckArrayEquals(computed_array, expected);
}
////////////////////////////
// Test pass_value_or_ref.
////////////////////////////
// Wrap into this helper struct, such that the type is printed on errors.
template <typename T1, typename T2>
struct CheckIsSame {
static_assert(std::is_same<T1, T2>::value, "test failure");
};
#define TEST_PASS_VALUE_OR_REF0(remove_extend, expected, given) \
static_assert( \
sizeof(CheckIsSame<expected, \
pass_value_or_ref<given, remove_extend>::type>) > 0, \
"check")
#define TEST_PASS_VALUE_OR_REF(expected, given) \
static_assert( \
sizeof(CheckIsSame<expected, pass_value_or_ref<given>::type>) > 0, \
"check")
TEST_PASS_VALUE_OR_REF(int, int&);
TEST_PASS_VALUE_OR_REF(int, int&&);
TEST_PASS_VALUE_OR_REF(const char*, const char[14]);
TEST_PASS_VALUE_OR_REF(const char*, const char*&&);
TEST_PASS_VALUE_OR_REF(const char*, const char (&)[14]);
TEST_PASS_VALUE_OR_REF(const std::string&, std::string);
TEST_PASS_VALUE_OR_REF(const std::string&, std::string&);
TEST_PASS_VALUE_OR_REF(const std::string&, const std::string&);
TEST_PASS_VALUE_OR_REF(int, const int);
TEST_PASS_VALUE_OR_REF(int, const int&);
TEST_PASS_VALUE_OR_REF(const int*, const int*);
TEST_PASS_VALUE_OR_REF(const int*, const int* const);
TEST_PASS_VALUE_OR_REF0(false, const char[14], const char[14]);
TEST_PASS_VALUE_OR_REF0(false, const char[14], const char (&)[14]);
TEST_PASS_VALUE_OR_REF0(false, const std::string&, std::string);
TEST_PASS_VALUE_OR_REF0(false, const std::string&, std::string&);
TEST_PASS_VALUE_OR_REF0(false, const std::string&, const std::string&);
TEST_PASS_VALUE_OR_REF0(false, int, const int);
TEST_PASS_VALUE_OR_REF0(false, int, const int&);
//////////////////////////////
// Test has_output_operator.
//////////////////////////////
// Intrinsic types:
static_assert(has_output_operator<int>::value, "int can be output");
static_assert(has_output_operator<void*>::value, "void* can be output");
static_assert(has_output_operator<uint64_t>::value, "int can be output");
// Classes:
class TestClass1 {};
class TestClass2 {};
extern std::ostream& operator<<(std::ostream& str, const TestClass2&);
class TestClass3 {};
extern std::ostream& operator<<(std::ostream& str, TestClass3);
static_assert(!has_output_operator<TestClass1>::value,
"TestClass1 can not be output");
static_assert(has_output_operator<TestClass2>::value,
"non-const TestClass2 can be output");
static_assert(has_output_operator<const TestClass2>::value,
"const TestClass2 can be output");
static_assert(has_output_operator<TestClass3>::value,
"non-const TestClass3 can be output");
static_assert(has_output_operator<const TestClass3>::value,
"const TestClass3 can be output");
//////////////////////////////
// Test fold.
//////////////////////////////
struct FoldAllSameType {
constexpr uint32_t operator()(uint32_t a, uint32_t b) const { return a | b; }
};
static_assert(base::fold(FoldAllSameType{}, 3, 6) == 7, "check fold");
// Test that it works if implicit conversion is needed for one of the
// parameters.
static_assert(base::fold(FoldAllSameType{}, uint8_t{1}, 256) == 257,
"check correct type inference");
// Test a single parameter.
static_assert(base::fold(FoldAllSameType{}, 25) == 25,
"check folding a single argument");
TEST(TemplateUtilsTest, FoldDifferentType) {
auto fn = [](std::string str, char c) {
str.push_back(c);
return str;
};
CHECK_EQ(base::fold(fn, std::string("foo"), 'b', 'a', 'r'), "foobar");
}
TEST(TemplateUtilsTest, FoldMoveOnlyType) {
auto fn = [](std::unique_ptr<std::string> str, char c) {
str->push_back(c);
return str;
};
std::unique_ptr<std::string> str = base::make_unique<std::string>("foo");
std::unique_ptr<std::string> folded =
base::fold(fn, std::move(str), 'b', 'a', 'r');
CHECK_NULL(str);
CHECK_NOT_NULL(folded);
CHECK_EQ(*folded, "foobar");
}
struct TemplatizedFoldFunctor {
template <typename T, typename... Tup>
std::tuple<Tup..., typename std::decay<T>::type> operator()(
std::tuple<Tup...> tup, T&& val) {
return std::tuple_cat(std::move(tup),
std::make_tuple(std::forward<T>(val)));
}
};
TEST(TemplateUtilsTest, FoldToTuple) {
auto input = std::make_tuple(char{'x'}, int{4}, double{3.2},
std::unique_ptr<uint8_t>{}, std::string{"foo"});
auto result =
base::fold(TemplatizedFoldFunctor{}, std::make_tuple(),
std::get<0>(input), std::get<1>(input), std::get<2>(input),
std::unique_ptr<uint8_t>{}, std::get<4>(input));
static_assert(std::is_same<decltype(result), decltype(input)>::value,
"the resulting tuple should have the same type as the input");
DCHECK_EQ(input, result);
}
} // namespace template_utils_unittest
} // namespace base
} // namespace v8