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#include "function_ref.h"
#include <library/cpp/testing/unittest/registar.h>
Y_UNIT_TEST_SUITE(TestFunctionRef) {
template <typename Signature>
struct TTestFunction;
template <typename Ret, typename... Args, bool IsNoexcept>
struct TTestFunction<Ret(Args...) noexcept(IsNoexcept)> {
Ret operator()(Args...) const noexcept(IsNoexcept) {
return {};
}
};
Y_UNIT_TEST(NonDefaultConstructible) {
static_assert(!std::is_default_constructible_v<TFunctionRef<void()>>);
static_assert(!std::is_default_constructible_v<TFunctionRef<void() noexcept>>);
static_assert(!std::is_default_constructible_v<TFunctionRef<int(double, void********* megaptr, TTestFunction<void(int)>)>>);
}
int F1(bool x) {
if (x)
throw 19;
return 42;
}
int F2(bool x) noexcept {
return 42 + x;
}
static const TTestFunction<int(bool)> C1;
static const TTestFunction<int(bool) noexcept> C2;
Y_UNIT_TEST(Noexcept) {
static_assert(std::is_constructible_v<TFunctionRef<int(bool)>, decltype(F1)>);
static_assert(std::is_constructible_v<TFunctionRef<int(bool)>, decltype(F2)>);
static_assert(!std::is_constructible_v<TFunctionRef<int(bool) noexcept>, decltype(F1)>);
static_assert(std::is_constructible_v<TFunctionRef<int(bool) noexcept>, decltype(F2)>);
static_assert(std::is_constructible_v<TFunctionRef<int(bool)>, decltype(C1)>);
static_assert(std::is_constructible_v<TFunctionRef<int(bool)>, decltype(C2)>);
static_assert(!std::is_constructible_v<TFunctionRef<int(bool) noexcept>, decltype(C1)>);
static_assert(std::is_constructible_v<TFunctionRef<int(bool) noexcept>, decltype(C2)>);
}
Y_UNIT_TEST(Deduction) {
TFunctionRef ref1(F1);
TFunctionRef ref2(F2);
TFunctionRef ref3(C1);
TFunctionRef ref4(C2);
static_assert(!std::is_nothrow_invocable_r_v<int, decltype(ref1), bool>);
static_assert(std::is_nothrow_invocable_r_v<int, decltype(ref2), bool>);
static_assert(std::is_same_v<decltype(ref1)::TSignature, int(bool)>);
static_assert(std::is_same_v<decltype(ref2)::TSignature, int(bool) noexcept>);
}
void WithCallback(TFunctionRef<double(double, int) noexcept>);
void Iterate(int from, int to, TFunctionRef<void(int)> callback) {
while (from < to) {
callback(from++);
}
}
void IterateNoexcept(int from, int to, TFunctionRef<void(int) noexcept> callback) {
while (from < to) {
callback(from++);
}
}
Y_UNIT_TEST(AsArgument) {
int sum = 0;
Iterate(0, 10, [&](int x) { sum += x; });
UNIT_ASSERT_EQUAL(sum, 45);
Iterate(0, 10, [&](int x) noexcept { sum += x; });
UNIT_ASSERT_EQUAL(sum, 90);
IterateNoexcept(0, 10, [&](int x) noexcept { sum += x; });
UNIT_ASSERT_EQUAL(sum, 135);
auto summer = [&](int x) { sum += x; };
Iterate(0, 10, summer);
Iterate(0, 10, summer);
Iterate(0, 10, summer);
UNIT_ASSERT_EQUAL(sum, 270);
TFunctionRef ref = summer;
Iterate(0, 10, ref);
UNIT_ASSERT_EQUAL(sum, 315);
}
int GlobalSum = 0;
void AddToGlobalSum(int x) {
GlobalSum += x;
}
Y_UNIT_TEST(FunctionPointer) {
GlobalSum = 0;
Iterate(0, 10, AddToGlobalSum);
UNIT_ASSERT_EQUAL(GlobalSum, 45);
TFunctionRef ref1 = AddToGlobalSum;
Iterate(0, 10, ref1);
UNIT_ASSERT_EQUAL(GlobalSum, 90);
TFunctionRef ref2{AddToGlobalSum};
Iterate(0, 10, ref2);
UNIT_ASSERT_EQUAL(GlobalSum, 135);
}
Y_UNIT_TEST(Reassign) {
TFunctionRef kek = [](double) { return 42; };
kek = [](double) { return 19; };
kek = [](int) { return 22.8; };
}
const char* Greet() {
return "Hello, world!";
}
Y_UNIT_TEST(ImplicitCasts) {
TFunctionRef<void(int)> ref = [](int x) { return x; };
ref = [](double x) { return x; };
ref = [](char x) { return x; };
TFunctionRef<int()> ref1 = [] { return 0.5; };
ref1 = [] { return 'a'; };
ref1 = [] { return 124u; };
TFunctionRef<TStringBuf()> ref2{Greet};
}
Y_UNIT_TEST(StatelessLambdaLifetime) {
TFunctionRef<int(int, int)> ref{[](int a, int b) { return a + b; }};
UNIT_ASSERT_EQUAL(ref(5, 5), 10);
}
Y_UNIT_TEST(ForwardArguments) {
char x = 'x';
TFunctionRef<void(std::unique_ptr<int>, char&)> ref = [](std::unique_ptr<int> ptr, char& ch) {
UNIT_ASSERT_EQUAL(*ptr, 5);
ch = 'a';
};
ref(std::make_unique<int>(5), x);
UNIT_ASSERT_EQUAL(x, 'a');
}
}
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