catch2/include/internal/catch_enum_values_registry.cpp

/*
 *  Created by Phil on 4/4/2019.
 *  Copyright 2019 Two Blue Cubes Ltd. All rights reserved.
 *
 *  Distributed under the Boost Software License, Version 1.0. (See accompanying
 *  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 */
#include "catch_enum_values_registry.h"
#include "catch_string_manip.h"
#include "catch_stream.h"

#include <map>
#include <cassert>

namespace Catch {

    IMutableEnumValuesRegistry::~IMutableEnumValuesRegistry() {}

    namespace Detail {

        namespace {
            // Extracts the actual name part of an enum instance
            // In other words, it returns the Blue part of Bikeshed::Colour::Blue
            StringRef extractInstanceName(StringRef enumInstance) {
                // Find last occurrence of ":"
                size_t name_start = enumInstance.size();
                while (name_start > 0 && enumInstance[name_start - 1] != ':') {
                    --name_start;
                }
                return enumInstance.substr(name_start, enumInstance.size() - name_start);
            }
        }

        std::vector<StringRef> parseEnums( StringRef enums ) {
            auto enumValues = splitStringRef( enums, ',' );
            std::vector<StringRef> parsed;
            parsed.reserve( enumValues.size() );
            for( auto const& enumValue : enumValues ) {
                parsed.push_back(trim(extractInstanceName(enumValue)));
            }
            return parsed;
        }

        EnumInfo::~EnumInfo() {}

        StringRef EnumInfo::lookup( int value ) const {
            for( auto const& valueToName : m_values ) {
                if( valueToName.first == value )
                    return valueToName.second;
            }
            return "{** unexpected enum value **}"_sr;
        }

        std::unique_ptr<EnumInfo> makeEnumInfo( StringRef enumName, StringRef allValueNames, std::vector<int> const& values ) {
            std::unique_ptr<EnumInfo> enumInfo( new EnumInfo );
            enumInfo->m_name = enumName;
            enumInfo->m_values.reserve( values.size() );

            const auto valueNames = Catch::Detail::parseEnums( allValueNames );
            assert( valueNames.size() == values.size() );
            std::size_t i = 0;
            for( auto value : values )
                enumInfo->m_values.emplace_back(value, valueNames[i++]);

            return enumInfo;
        }

        EnumInfo const& EnumValuesRegistry::registerEnum( StringRef enumName, StringRef allValueNames, std::vector<int> const& values ) {
            m_enumInfos.push_back(makeEnumInfo(enumName, allValueNames, values));
            return *m_enumInfos.back();
        }

    } // Detail
} // Catch