Catch2/projects/SelfTest/EnumToString.cpp

#include "catch.hpp"


// Enum without user-provided stream operator
enum Enum1 { Enum1Value0, Enum1Value1 };

TEST_CASE( "toString(enum)", "[toString][enum]" ) {
    Enum1 e0 = Enum1Value0;
    CHECK( ::Catch::Detail::stringify(e0) == "0" );
    Enum1 e1 = Enum1Value1;
    CHECK( ::Catch::Detail::stringify(e1) == "1" );
}

// Enum with user-provided stream operator
enum Enum2 { Enum2Value0, Enum2Value1 };

std::ostream& operator<<( std::ostream& os, Enum2 v ) {
    return os << "E2{" << static_cast<int>(v) << "}";
}

TEST_CASE( "toString(enum w/operator<<)", "[toString][enum]" ) {
    Enum2 e0 = Enum2Value0;
    CHECK( ::Catch::Detail::stringify(e0) == "E2{0}" );
    Enum2 e1 = Enum2Value1;
    CHECK( ::Catch::Detail::stringify(e1) == "E2{1}" );
}

// Enum class without user-provided stream operator
enum class EnumClass1 { EnumClass1Value0, EnumClass1Value1 };

// This fails, but has been hidden for a while - not sure if it's a regression or if it never worked
// - need to investigate
TEST_CASE( "toString(enum class)", "[toString][enum][enumClass][.]" ) {
    EnumClass1 e0 = EnumClass1::EnumClass1Value0;
    CHECK( ::Catch::Detail::stringify(e0) == "0" );
    EnumClass1 e1 = EnumClass1::EnumClass1Value1;
    CHECK( ::Catch::Detail::stringify(e1) == "1" );
}

// Enum class with user-provided stream operator
enum class EnumClass2 : short { EnumClass2Value0, EnumClass2Value1 };

std::ostream& operator<<( std::ostream& os, EnumClass2 e2 ) {
    switch( static_cast<int>( e2 ) ) {
        case static_cast<int>( EnumClass2::EnumClass2Value0 ):
            return os << "E2/V0";
        case static_cast<int>( EnumClass2::EnumClass2Value1 ):
            return os << "E2/V1";
        default:
            return os << "Unknown enum value " << static_cast<int>( e2 );
    }
}

TEST_CASE( "toString(enum class w/operator<<)", "[toString][enum][enumClass]" ) {
    EnumClass2 e0 = EnumClass2::EnumClass2Value0;
    CHECK( ::Catch::Detail::stringify(e0) == "E2/V0" );
    EnumClass2 e1 = EnumClass2::EnumClass2Value1;
    CHECK( ::Catch::Detail::stringify(e1) == "E2/V1" );

    EnumClass2 e3 = static_cast<EnumClass2>(10);
    CHECK( ::Catch::Detail::stringify(e3) == "Unknown enum value 10" );
}