Fix variant test for libstdc++ version 9 (#1515)

By using non-trivially copyable types, we force libstdc++-9's variant to
properly enter the valueless-by-exception state for our stringification
test.

Related to #1511
This commit is contained in:
Robin Moussu 2019-01-26 18:32:17 +01:00 committed by Martin Hořeňovský
parent 6f9cdd6583
commit a2baabbf71

View File

@ -6,6 +6,18 @@
#include <string>
#include <variant>
// We need 2 types with non-trivial copies/moves
struct MyType1 {
MyType1() = default;
MyType1(MyType1 const&) { throw 1; }
MyType1& operator=(MyType1 const&) { throw 3; }
};
struct MyType2 {
MyType2() = default;
MyType2(MyType2 const&) { throw 2; }
MyType2& operator=(MyType2 const&) { throw 4; }
};
TEST_CASE( "variant<std::monostate>", "[toString][variant][approvals]")
{
using type = std::variant<std::monostate>;
@ -26,18 +38,17 @@ TEST_CASE( "variant<float, int>", "[toString][variant][approvals]")
using type = std::variant<float, int>;
CHECK( "0.5f" == ::Catch::Detail::stringify(type{0.5f}) );
CHECK( "0" == ::Catch::Detail::stringify(type{0}) );
}
SECTION("valueless by exception") {
struct sample {
operator int() const { throw 42; }
};
TEST_CASE( "variant -- valueless-by-exception", "[toString][variant][approvals]" ) {
using type = std::variant<MyType1, MyType2>;
type value{1.5f};
REQUIRE_THROWS_AS( value.emplace<int>(sample{}), int );
type value;
REQUIRE_THROWS_AS(value.emplace<MyType2>(MyType2{}), int);
REQUIRE(value.valueless_by_exception());
CHECK("{valueless variant}" == ::Catch::Detail::stringify(value));
}
}
TEST_CASE( "variant<string, int>", "[toString][variant][approvals]")
{
@ -48,7 +59,7 @@ TEST_CASE( "variant<string, int>", "[toString][variant][approvals]")
TEST_CASE( "variant<variant<float, int>, string>", "[toString][variant][approvals]")
{
using inner = std::variant<float, int>;
using inner = std::variant<MyType1, float, int>;
using type = std::variant<inner, std::string>;
CHECK( "0.5f" == ::Catch::Detail::stringify(type{0.5f}) );
CHECK( "0" == ::Catch::Detail::stringify(type{0}) );
@ -63,7 +74,7 @@ TEST_CASE( "variant<variant<float, int>, string>", "[toString][variant][approval
REQUIRE( std::holds_alternative<inner>(value) );
REQUIRE( std::holds_alternative<float>(std::get<inner>(value)) );
REQUIRE_THROWS_AS( std::get<0>(value).emplace<int>(sample{}), int );
REQUIRE_THROWS_AS( std::get<0>(value).emplace<MyType1>(MyType1{}), int );
// outer variant is still valid and contains inner
REQUIRE( std::holds_alternative<inner>(value) );