scope-guard/test/UniqueResourceTest.cpp

/*
 * Scope Guard
 * Copyright (C) 2017-2018  offa
 *
 * This file is part of Scope Guard.
 *
 * Scope Guard is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Scope Guard is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Scope Guard.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "unique_resource.h"
#include "CallMocks.h"
#include <catch.hpp>
#include <trompeloeil.hpp>

using namespace mock;
using namespace trompeloeil;

namespace
{
    CallMock m;

    void deleter(Handle h)
    {
        m.deleter(h);
    }
}

TEST_CASE("construction with move", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    [[maybe_unused]] auto guard = sr::unique_resource{Handle{3}, deleter};
}

TEST_CASE("construction with copy", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    const Handle h{3};
    const auto d = [](auto v) { m.deleter(v); };
    [[maybe_unused]] auto guard = sr::unique_resource{h, d};
}

TEST_CASE("construction with copy calls deleter and rethrows on failed copy", "[UniqueResource]")
{
    REQUIRE_THROWS([] {
        const ThrowOnCopyMock noMove;
        const auto d = [](const auto&) { m.deleter(3); };
        REQUIRE_CALL(m, deleter(3));

        [[maybe_unused]] sr::unique_resource guard{noMove, d};
    }());
}

TEST_CASE("move-construction with move", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    auto movedFrom = sr::unique_resource{Handle{3}, deleter};
    auto guard = std::move(movedFrom);
    CHECK(guard.get() == 3);
}

TEST_CASE("move-construction with copy", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(7));
    auto d = [](auto) { deleter(7); };

    const CopyMock copyMock;
    sr::unique_resource movedFrom{copyMock, d};
    [[maybe_unused]] auto guard = std::move(movedFrom);
}

TEST_CASE("move assignment calls deleter", "[UniqueResource]")
{
    auto moveFrom = sr::unique_resource{Handle{3}, deleter};
    REQUIRE_CALL(m, deleter(4));

    {
        REQUIRE_CALL(m, deleter(3));
        auto guard = sr::unique_resource{Handle{4}, deleter};
        guard = std::move(moveFrom);
    }
}

TEST_CASE("deleter called on destruction", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    [[maybe_unused]] auto guard = sr::unique_resource{Handle{3}, deleter};
}

TEST_CASE("reset calls deleter", "[UniqueResource]")
{
    auto guard = sr::unique_resource{Handle{3}, deleter};

    {
        REQUIRE_CALL(m, deleter(3));
        guard.reset();
    }
}

TEST_CASE("reset does not call deleter if released", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3)).TIMES(0);
    auto guard = sr::unique_resource{Handle{3}, deleter};
    guard.release();
    guard.reset();
}

TEST_CASE("reset sets new rvalue and calls deleter on previous", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    REQUIRE_CALL(m, deleter(7));
    auto guard = sr::unique_resource{Handle{3}, deleter};
    guard.reset(Handle{7});
}

TEST_CASE("reset sets new lvalue and calls deleter on previous", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    REQUIRE_CALL(m, deleter(7));
    auto d = [](const auto& v) { deleter(v.m_value); };
    auto guard = sr::unique_resource{NotNothrowAssignable{3}, d};
    const NotNothrowAssignable h{7};
    guard.reset(h);
}

TEST_CASE("reset handles exception on assignment", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    REQUIRE_CALL(m, deleter(7));
    auto d = [](const auto& v) { deleter(v.m_handle); };
    auto guard = sr::unique_resource{ConditialThrowOnCopyMock{3, false}, d};
    guard.reset(ConditialThrowOnCopyMock{7, true});
}

TEST_CASE("release disables deleter", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3)).TIMES(0);
    auto guard = sr::unique_resource{Handle{3}, deleter};
    guard.release();
}

TEST_CASE("get returns resource", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    auto guard = sr::unique_resource{Handle{3}, deleter};
    CHECK(guard.get() == 3);
}

TEST_CASE("pointer access returns resource" "[UniqueResource]")
{
    const auto p = std::make_pair(3, 4);
    auto guard = sr::unique_resource{&p, [](auto*) { }};
    REQUIRE(guard->first == 3);
    REQUIRE(guard->second == 4);
}

TEST_CASE("pointer dereference returns resource" "[UniqueResource]")
{
    Handle h{5};
    auto guard = sr::unique_resource{PtrHandle{&h}, [](auto*) { }};
    REQUIRE(*guard == 5);
}

TEST_CASE("deleter access", "[UniqueResource]")
{
    auto guard = sr::unique_resource{Handle{3}, deleter};
    guard.release();

    {
        REQUIRE_CALL(m, deleter(8));
        guard.get_deleter()(8);
    }
}

TEST_CASE("make unique resource", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(7));
    [[maybe_unused]] auto guard = sr::unique_resource{Handle{7}, deleter};
}

TEST_CASE("make unique resource with reference wrapper", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(3));
    Handle h{3};
    [[maybe_unused]] auto guard = sr::unique_resource{std::ref(h), deleter};
}

TEST_CASE("make unique resource checked", "[UniqueResource]")
{
    REQUIRE_CALL(m, deleter(4));
    [[maybe_unused]] auto guard = sr::make_unique_resource_checked(Handle{4}, Handle{-1}, deleter);
}

TEST_CASE("make unique resource checked releases if invalid", "[UniqueResource]")
{
    [[maybe_unused]] auto guard = sr::make_unique_resource_checked(Handle{-1}, Handle{-1}, deleter);
}