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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
// UNSUPPORTED: no-exceptions
// <flat_set>
// template<class Key, class Compare, class KeyContainer, class Predicate>
// typename flat_set<Key, Compare, KeyContainer>::size_type
// erase_if(flat_set<Key, Compare, KeyContainer>& c, Predicate pred);
// If any member function in [flat.set.defn] exits via an exception, the invariant is restored.
// (This is not a member function, but let's respect the invariant anyway.)
#include <algorithm>
#include <cassert>
#include <deque>
#include <flat_set>
#include <functional>
#include <utility>
#include <vector>
#include "../helpers.h"
#include "test_macros.h"
struct Counter {
int c1, c2, throws;
void tick() {
c1 -= 1;
if (c1 == 0) {
c1 = c2;
throws += 1;
throw 42;
}
}
};
Counter g_counter = {0, 0, 0};
struct ThrowingAssignment {
ThrowingAssignment(int i) : i_(i) {}
ThrowingAssignment(const ThrowingAssignment&) = default;
ThrowingAssignment& operator=(const ThrowingAssignment& rhs) {
g_counter.tick();
i_ = rhs.i_;
g_counter.tick();
return *this;
}
operator int() const { return i_; }
int i_;
};
struct ThrowingComparator {
bool operator()(const ThrowingAssignment& a, const ThrowingAssignment& b) const {
g_counter.tick();
return a.i_ < b.i_;
}
};
struct ErasurePredicate {
bool operator()(const auto& x) const { return (3 <= x && x <= 5); }
};
void test() {
const int expected[] = {1, 2, 3, 4, 5, 6, 7, 8};
{
using M = std::flat_set<ThrowingAssignment, ThrowingComparator>;
for (int first_throw = 1; first_throw < 99; ++first_throw) {
for (int second_throw = 1; second_throw < 99; ++second_throw) {
g_counter = {0, 0, 0};
M m = M({1, 2, 3, 4, 5, 6, 7, 8});
try {
g_counter = {first_throw, second_throw, 0};
auto n = std::erase_if(m, ErasurePredicate());
assert(n == 3);
// If it didn't throw at all, we're done.
g_counter = {0, 0, 0};
assert((m == M{1, 2, 6, 7, 8}));
first_throw = 99; // "done"
break;
} catch (int ex) {
assert(ex == 42);
check_invariant(m);
LIBCPP_ASSERT(m.empty() || std::equal(m.begin(), m.end(), expected, expected + 8));
if (g_counter.throws == 1) {
// We reached the first throw but not the second throw.
break;
}
}
}
}
}
{
using M = std::flat_set<ThrowingAssignment, ThrowingComparator, std::deque<ThrowingAssignment>>;
for (int first_throw = 1; first_throw < 99; ++first_throw) {
for (int second_throw = 1; second_throw < 99; ++second_throw) {
g_counter = {0, 0, 0};
std::deque<ThrowingAssignment> container = {5, 6, 7, 8};
container.insert(container.begin(), {1, 2, 3, 4});
M m = M(std::move(container));
try {
g_counter = {first_throw, second_throw, 0};
auto n = std::erase_if(m, ErasurePredicate());
assert(n == 3);
// If it didn't throw at all, we're done.
g_counter = {0, 0, 0};
assert((m == M{1, 2, 6, 7, 8}));
first_throw = 99; // "done"
break;
} catch (int ex) {
assert(ex == 42);
check_invariant(m);
LIBCPP_ASSERT(m.empty() || std::equal(m.begin(), m.end(), expected, expected + 8));
if (g_counter.throws == 1) {
// We reached the first throw but not the second throw.
break;
}
}
}
}
}
}
int main(int, char**) {
test();
return 0;
}
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