nb::Error objects now working

CMakeLists.txt

@@ -48,13 +48,12 @@ if(NB_BUILD_TESTS)
     include(FetchContent)
     FetchContent_Declare(
         gtest
-        URL https://github.com/google/googletest/archive/refs/tags/release-1.12.1.zip
+        URL https://github.com/google/googletest/archive/refs/heads/main.zip
     )
     if (WIN32)
         set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
         FetchContent_MakeAvailable(gtest)
     endif()
-    include(GoogleTest)
     set(GTEST_COLOR ON)
     set(GLFW_BUILD_TESTS ON CACHE BOOL "" FORCE)
 endif()

engine/NBCore/ANSITerm.hpp

@@ -2,16 +2,10 @@
 #ifndef _NB_ANSI_TERM
 #define _NB_ANSI_TERM
 
-#include <array>
-#include <cmath>
-#include <iomanip>
 #include <iostream>
 #include <string>
-#include <tuple>
 #include <type_traits>
 
-#include "TypeTraits.hpp"
-
 /*
 ----------- TECH DEBT ------------
 Idk wtf to do here. This was originally to allow me to print 

engine/NBCore/CMakeLists.txt

@@ -1,9 +1,8 @@
-include_directories(./.)
-
 toAbsolutePath(NB_CORE_SOURCE 
     ./src/Errors.cpp
+#    ./src/Logger.cpp
     ./src/Processes.cpp
-    ./src/Logger.cpp
+    ./src/Utils.cpp
 )
 
 toAbsolutePath(NB_CORE_INCLUDE
@@ -15,6 +14,7 @@ toAbsolutePath(NB_CORE_INCLUDE
     ./ThreadsafeQueue.hpp
     ./Types.hpp
     ./TypeTraits.hpp
+    ./Utils.hpp
 )
 
 set(NB_CORE_SOURCE ${NB_CORE_SOURCE} PARENT_SCOPE)
@@ -22,6 +22,8 @@ set(NB_CORE_INCLUDE ${NB_CORE_INCLUDE} PARENT_SCOPE)
 
 add_library(NBCore ${NB_CORE_SOURCE})
 
+target_include_directories(NBCore PUBLIC ./.)
+
 if (NB_BUILD_TESTS)
     add_subdirectory(./tests)
 endif()

engine/NBCore/Errors.hpp

@@ -5,10 +5,13 @@
 #include <exception>
 #include <memory>
 #include <string>
+#include <string_view>
 #include <type_traits>
+#include "TypeTraits.hpp"
 #include <unordered_map>
+#include "Utils.hpp"
 
-#ifndef THROW_WITH_INFO
+/* #ifndef THROW_WITH_INFO
     #ifdef CODE_ERROR_LOCATIONS
         #define THROW_WITH_INFO(type, ...) throw type(__VA_ARGS__, __LINE__, __FILE__)
     #else
@@ -22,118 +25,234 @@
     #else
         #define THROW(...) THROW_WITH_INFO(__VA_ARGS__)
     #endif // LOGGING
-#endif // THROW
+#endif // THROW */
 
 namespace nb {
 
 typedef std::unordered_map<unsigned int, const char*> ErrorCodeMap;
 
-template<class ErrorType>
-class ErrorBase : public std::exception {
-public:
-    ErrorBase(
-        const unsigned int code,
-        unsigned int line=0,
-        std::string filename=""
-    ) noexcept : ErrorBase(
-        code, 
-        ErrorBase<ErrorType>::lookup(code),
-        line,
-        filename
-    ) {}
-    ErrorBase(
-        const unsigned int code,
-        const std::exception& trace,
-        unsigned int line=0,
-        std::string filename=""
-    ) noexcept : ErrorBase(
-        code, 
-        ErrorBase<ErrorType>::lookup(code),
-        trace,
-        line,
-        filename
-    ) {}
+template <typename T>
+using has_type = decltype(T::type);
 
-    static std::string lookup(unsigned int);
-    unsigned int code() const noexcept {
-        return static_cast<const ErrorType*>(this)->_code;
-    };
-    virtual const char* what() const noexcept override final { return _msg.c_str(); };
+template<class ErrorType = NoneType>
+class ErrorBase;
+
+template<>
+class ErrorBase<NoneType> : public std::exception {
+public:
+    const unsigned int code;
+    const std::string msg;
+    const std::shared_ptr<const std::exception> trace;
+    const bool traceIsNBError;
+
+    virtual inline std::string str() const noexcept = 0;
+
+    virtual const char* what() const noexcept override final {
+        const std::string& ret = str();
+        return ret.c_str();
+    }
 
 protected:
-    ErrorBase() = default;
+    template <
+        typename TraceType = std::exception,
+        std::enable_if_t<std::is_base_of_v<std::exception, TraceType>, bool> = true
+    >
     ErrorBase(
-        const unsigned int code,
-        std::string msg,
-        unsigned int line=0,
-        std::string filename=""
-    ) noexcept : _code{code}, _msg{""} {
+        const unsigned int& code_,
+        const std::string& msg_,
+        const std::shared_ptr<TraceType> trace_,
+        const unsigned int& line_,
+        std::string filename_
+    ) noexcept :
+        code(code_),
+        msg(msg_),
+        trace{std::dynamic_pointer_cast<std::exception>(trace_)},
+        traceIsNBError( trace_ ? is_detected<has_type, TraceType>::value : false)
+    {
+        static_assert(std::is_base_of<std::exception, TraceType>::value,
+            "`trace_` must be a pointer to a child object of std::exception."
+        );
+    }
+};
+
+template <class ErrorType>
+class ErrorBase : public ErrorBase<NoneType> {
+    using Base = ErrorBase<NoneType>;
+public:
+    ErrorBase(const ErrorBase&) = default;
+    ErrorBase& operator=(const ErrorBase&) = delete;
+
+    virtual inline std::string str() const noexcept override {
+        std::string ret = msg;
+        if (trace) {
+            const std::string replace = nb::NEWLINE+"  ";
+            std::string trace_msg;
+            if (traceIsNBError) { 
+                trace_msg = std::static_pointer_cast<const ErrorBase>(trace)->str();
+                trace_msg = std::string(std::string_view(trace_msg).substr(
+                    0, trace_msg.length()-nb::NEWLINE.length()
+                ));
+            } else {
+                trace_msg = std::string(trace->what());
+            }
+            ret += replace + "Trace: " + find_and_replace<std::string>(
+                trace_msg,
+                nb::NEWLINE,
+                replace
+            );
+        }
+        return ret + nb::NEWLINE;
+    }
+
+    static const std::string type;
+    static const ErrorCodeMap ErrorMessages; 
+
+    using Base::code;
+    using Base::msg;
+    using Base::trace;
+    using Base::traceIsNBError;
+
+protected:
+    using Base::Base;
+
+    template <
+        typename TraceType = std::exception,
+        std::enable_if_t<std::is_base_of_v<std::exception, TraceType>, bool> = true
+    >
+    ErrorBase(
+        const unsigned int code_,
+        std::string msg_,
+        const TraceType* trace_=nullptr,
+        unsigned int line_=0,
+        std::string filename_=""
+    ) : Base(
+        code_,
+        msg_, 
+        trace_ ? std::make_shared<TraceType>(*trace_) : nullptr, 
+        line_, 
+        filename_
+    ) {
         static_assert(std::is_same<const std::unordered_map<unsigned int, const char*>, decltype(ErrorType::ErrorMessages)>::value,
             "const std::unordered_map<unsigned int, const char*> ErrorMessages must be "
             "a class member."
         );
-        static_assert(std::is_enum_v<typename ErrorType::ErrorCodes>, "enum ErrorCodes must be a class member.");
-        static_assert(std::is_same<std::underlying_type_t<typename ErrorType::ErrorCodes>, unsigned int>::value,
-            "enum ErrorCodes must be of underlying type unsigned int."
+        static_assert(std::is_enum_v<typename ErrorType::Codes>, "enum Codes must be a class member.");
+        static_assert(std::is_same<std::underlying_type_t<typename ErrorType::Codes>, unsigned int>::value,
+            "enum Codes must be of underlying type unsigned int."
         );
         static_assert(std::is_same<const std::string, decltype(ErrorType::type)>::value,
             "const std::string type must be a class member."
         );
-
-        _msg += std::string(ErrorType::type);
-        _msg += "[" + std::to_string(_code) + "]";
-        if (line && filename.size()) {
-            _msg += " in \'" + filename + "\':" + std::to_string(line);
-        }
-        _msg += "\n    " + msg;
     }
+
+    template <
+        typename TraceType,
+        std::enable_if_t<std::is_base_of_v<std::exception, TraceType>, bool> = true
+    >
     ErrorBase(
-        const unsigned int code,
-        std::string msg,
-        const std::exception& trace,
-        unsigned int line=0,
-        std::string filename=""
-    ) noexcept : ErrorBase(code, msg, line, filename) {
-        std::string what_msg(trace.what());
-        std::string::size_type newline_pos=-1;
-        while((newline_pos=what_msg.find("\n", newline_pos+1))!= std::string::npos) {
-            what_msg.replace(newline_pos, 1, "\n  ");
-        }
-        _msg += "\n    Trace - " + what_msg;
-    }
+        const unsigned int& code_,
+        const TraceType& trace_,
+        unsigned int line_=0,
+        std::string filename_=""
+    ) noexcept : ErrorBase(
+        code_, 
+        ErrorType::ErrorMessages.at(code_),
+        &trace_,
+        line_,
+        filename_
+    ) {}
 
-    unsigned int _code;
-    std::string _msg;
+    template <
+        typename TraceType,
+        std::enable_if_t<std::is_base_of_v<std::exception, TraceType>, bool> = true
+    >
+    ErrorBase(
+        const std::string& msg_,
+        const TraceType& trace_,
+        unsigned int line_=0,
+        std::string filename_=""
+    ) noexcept : ErrorBase(
+        0, 
+        msg_,
+        &trace_,
+        line_,
+        filename_
+    ) {}
+
+    ErrorBase(
+        const unsigned int& code_,
+        unsigned int line_=0,
+        std::string filename_=""
+    ) noexcept : ErrorBase(
+        code_, 
+        ErrorType::ErrorMessages.at(code_),
+        static_cast<std::exception*>(nullptr),
+        line_,
+        filename_
+    ) {}
+
+    ErrorBase(
+        const std::string& msg_,
+        unsigned int line_=0,
+        std::string filename_=""
+    ) noexcept : ErrorBase(
+        0, 
+        msg_,
+        nullptr,
+        line_,
+        filename_
+    ) {}
+};
+template <typename ErrorType>
+const std::string ErrorBase<ErrorType>::type = ErrorType::type;
+template <typename ErrorType>
+const ErrorCodeMap ErrorBase<ErrorType>::ErrorMessages = ErrorType::ErrorMessages;
+
+template <class ErrorType = NoneType>
+class Error;
+
+template<>
+class Error<NoneType>;
+
+template <class ErrorType>
+class Error : public ErrorBase<ErrorType> {
+    using Base = ErrorBase<ErrorType>;
+public:    
+    template <typename... Args>
+    Error(Args... T) : Base(T...) {}
+
+    using Base::str;
+    using Base::what;
+    using Base::code;
+    using Base::msg;
+    using Base::trace;
+    using Base::type;
+    using Base::ErrorMessages;
+
+    friend ErrorBase<Error>;
 };
 
-class Error : public ErrorBase<Error> {
+template<>
+class Error<NoneType> : public ErrorBase<Error<NoneType>> {
+    using Base = ErrorBase<Error<NoneType>>;
 public:
-    enum ErrorCodes : unsigned int {
+    using Base::Base;
+    Error() : Base(0) {}
+
+    enum Codes : unsigned int {
         GENERAL, UNDEFINED, BADERRORCODE
     };
 
-    using ErrorBase<Error>::ErrorBase;
+    using Base::str;
+    using Base::what;
+    using Base::code;
+    using Base::msg;
+    using Base::trace;
 
-    friend ErrorBase<Error>;
-
-protected:
     static const std::string type;
     static const ErrorCodeMap ErrorMessages;
-
 };
 
-template<class ErrorType>
-std::string ErrorBase<ErrorType>::lookup(unsigned int code) {
-    for (auto kv : ErrorType::ErrorMessages) {
-        if (kv.first==code) {
-            return std::string(kv.second);
-        }        
-    }
-
-    throw Error(Error::ErrorCodes::BADERRORCODE);
-}
-
 } // namespace nb
 
-
 #endif // _NB_ERROR

engine/NBCore/TypeTraits.hpp

@@ -6,7 +6,38 @@
 
 namespace nb {
 
-template<std::size_t N=0, typename Func, typename... Pack>
+namespace detail {
+    template <
+        class Default,
+        class AlwaysVoid,
+        template <class...> class Op,
+        class... Args
+    >
+    struct detector {
+        using value = std::false_type;
+        using type = Default;
+    };
+
+    template <
+        class Default, 
+        template <class...> class Op,
+        class... Args
+    >
+    struct detector<Default, std::void_t<Op<Args...>>, Op, Args...> {
+        using value = std::true_type;
+        using type = Op<Args...>;
+    };
+} // namespace detail
+
+struct NoneType{};
+
+template <
+    template <class...> class Op,
+    class... Args
+>
+using is_detected = typename detail::detector<NoneType, void, Op, Args...>::value;
+
+/*template<std::size_t N=0, typename Func, typename... Pack>
 inline typename std::enable_if<N==sizeof...(Pack), void>::type
 ForEach(std::tuple<Pack...>&, Func) {}
 
@@ -68,7 +99,7 @@ struct PackIsSameType<T, PackType> {
 template <typename T, typename FirstPack, typename... Pack>
 struct PackIsSameType<T, FirstPack, Pack...> {
     const bool value = std::is_base_of<T, FirstPack>::value && PackIsSameType<T, Pack...>::value;
-};
+};*/
 
 } // namespace nb
 

engine/NBCore/Types.hpp

@@ -1,25 +0,0 @@
-#pragma once
-#ifndef _NB_CORE_TYPES
-#define _NB_CORE_TYPES
-
-#include <vector>
-
-namespace nb {
-
-template<typename T>
-T swapEndian(const T& val) {
-    T ret;
-    const int size = sizeof(T);
-    auto retLoc = static_cast<void*>(&ret);
-    auto valLoc = static_cast<const void*>(&val);
-
-    for (int i = 0; i < size; ++i) {
-        memcpy(retLoc+i, valLoc+(size-i-1), 1);
-    }
-    return ret;
-}
-
-using ByteVector = std::vector<uint8_t>;
-
-} // namespace nb
-#endif // _NB_CORE_TYPES

engine/NBCore/Utils.hpp

@@ -0,0 +1,96 @@
+#pragma once
+#ifndef _NB_CORE_TYPES
+#define _NB_CORE_TYPES
+
+#include <iostream>
+#include <string>
+#include <type_traits>
+
+namespace nb {
+
+#ifdef _NB_TARGET_WINDOWS
+    const std::string NEWLINE = "\n";
+    const std::wstring WNEWLINE = L"\n";
+#endif // _NB_TARGET_WINDOWS
+#ifdef _NB_TARGET_LINUX
+    const std::string NEWLINE = "\n";
+    const std::wstring WNEWLINE = L"\n";
+#endif // _NB_TARGET_LINUX
+
+template<typename T>
+std::enable_if_t<std::is_convertible_v<T, std::string>, std::wstring> str_to_wstr(T in) {
+    std::string str(in);
+    std::wstring ret(str.begin(), str.end());
+    return ret;
+}
+
+template<typename T>
+std::enable_if_t<std::is_convertible_v<T, std::wstring>, std::string> wstr_to_str(T in) {
+    std::wstring wstr(in);
+    std::size_t wstrlen = wstr.length();
+    char* c_str= new char[wstrlen];
+    std::wcstombs(c_str, wstr.c_str(), wstrlen);
+    std::string ret(c_str, wstrlen);
+    delete[] c_str;
+    return ret;
+}
+
+template <typename Stream, typename... Args>
+void stream(Stream& s, Args&&... args);
+
+template <typename Stream, typename... Args>
+void stream(Stream& s, Args&&... args) {
+    (s << ... << args);
+}
+
+template<typename... Args>
+void term(Args&&... args) { stream(std::cout, args..., nb::NEWLINE); }
+
+template<typename... Args>
+void wterm(Args&&... args) { stream(std::wcout, args..., nb::WNEWLINE); }
+
+template <typename T = std::string, typename A, typename B, typename C>
+T find_and_replace(
+    A original,
+    B find,
+    C replace
+) {
+    const T& original_t = T(original);
+    const T& find_t = T(find);
+    const T& replace_t = T(replace); 
+
+    T ret = original_t;
+
+    std::size_t find_len = find_t.length();
+    std::size_t replace_len = replace_t.length();
+    std::size_t currpos = 0;
+    while(true) {
+        currpos = ret.find(find_t, currpos);
+        if (currpos == T::npos) {
+            break;
+        }
+        ret = ret.erase(currpos, find_len);
+        ret = ret.insert(currpos, replace_t);
+        currpos += replace_len;
+    }
+    return ret;
+}
+
+/* template<typename T>
+T swap_endian(const T& val) {
+    T ret;
+    const int size = sizeof(T);
+    auto retLoc = static_cast<void*>(&ret);
+    auto valLoc = static_cast<const void*>(&val);
+
+    for (int i = 0; i < size; ++i) {
+        memcpy(retLoc+i, valLoc+(size-i-1), 1);
+    }
+    return ret;
+} */
+
+
+// using ByteVector = std::vector<uint8_t>;
+
+} // namespace nb
+#endif // _NB_CORE_TYPES

engine/NBCore/src/Errors.cpp

@@ -1,12 +1,14 @@
 #include "Errors.hpp"
+#include "TypeTraits.hpp"
 
 namespace nb {
 
-const std::string Error::type =  "Error";
-const ErrorCodeMap Error::ErrorMessages = {
-    {ErrorCodes::GENERAL, "General std::exception."},
-    {ErrorCodes::UNDEFINED, "Undefined / general error."},
-    {ErrorCodes::BADERRORCODE, "Unrecognized error code."}
+const std::string Error<nb::NoneType>::type =  "nb::Error";
+
+const ErrorCodeMap Error<nb::NoneType>::ErrorMessages = {
+    {Error::Codes::GENERAL, "General std::exception."},
+    {Error::Codes::UNDEFINED, "Undefined / general error."},
+    {Error::Codes::BADERRORCODE, "Unrecognized error code."}
 };
 
 }

engine/NBCore/src/Processes.cpp

@@ -7,7 +7,6 @@
 #endif // _NB_TARGET_LINUX
 
 #include "Processes.hpp"
-#include "Types.hpp"
 
 namespace nb {
 

engine/NBCore/src/Utils.cpp

@@ -0,0 +1,8 @@
+#include <string>
+#include "Utils.hpp"
+
+template<>
+std::wstring nb::str_to_wstr(const std::string& in) {
+    std::wstring ret(in.begin(), in.end());
+    return ret;
+}

engine/NBCore/tests/CMakeLists.txt

@@ -4,8 +4,9 @@ if (NB_BUILD_TESTS)
     enable_testing()
     include(GoogleTest)
     add_executable(TestCore
-        testErrors.cpp
-        testProcesses.cpp
+        ./testErrors.cpp
+        #./testProcesses.cpp
+        ./testUtils.cpp
     )
     target_link_libraries(TestCore
         NBCore

engine/NBCore/tests/testErrors.cpp

@@ -1,38 +1,40 @@
 #define CODE_ERROR_LOCATIONS
 
-#include "Errors.hpp"
 #include <gtest/gtest.h>
-#include <iostream>
-#include <sstream>
-#include "Logger.hpp"
+
+#include "Errors.hpp"
+#include <string>
+#include "Utils.hpp"
 
 using namespace nb;
 
-class TestError : public ErrorBase<TestError> {
+class TestError : public Error<TestError> {
+    using Base = Error<TestError>;
 public:    
-    using ErrorBase<TestError>::ErrorBase;
+    using Base::Base;
+    using Base::what;
+    using Base::code;
+    using Base::msg;
+    using Base::trace;
 
-    enum ErrorCodes : unsigned int {
+    enum Codes : unsigned int {
         A, B, C, D
     };
+
     static const std::string type;
-    static const ErrorCodeMap ErrorMessages;
+    static const nb::ErrorCodeMap ErrorMessages;
 };
 
 const std::string TestError::type="TestError";
 const ErrorCodeMap TestError::ErrorMessages{
-    {TestError::ErrorCodes::A, "Hey!"},
-    {TestError::ErrorCodes::B, "How"},
-    {TestError::ErrorCodes::C, "You"},
-    {TestError::ErrorCodes::D, "Doin"}
+    {TestError::Codes::A, "Hey!"},
+    {TestError::Codes::B, "How"},
+    {TestError::Codes::C, "You"},
+    {TestError::Codes::D, "Doin"}
 };
 
 
 TEST(ErrorTest, Test) {
-    EXPECT_EQ(1, 1);
-
-    std::stringstream sstream;
-
-    ASSERT_TRUE(nb::logger.isRunning());
-    nb::logger.log("Hey!");
+    auto err = TestError(0, TestError(1, TestError(2, TestError(3, TestError(2)))));
+    ASSERT_STREQ(err.what(), "Hey!\n  Trace: How\n    Trace: You\n      Trace: Doin\n        Trace: You\n");
 }

engine/NBCore/tests/testProcesses.cpp

@@ -1,8 +1,6 @@
 #define CODE_ERROR_LOCATIONS
 
 #include <gtest/gtest.h>
-
-#include <iostream>
 #include "Processes.hpp"
 #include <Windows.h>
 

engine/NBCore/tests/testUtils.cpp

@@ -0,0 +1,148 @@
+#define CODE_ERROR_LOCATIONS
+
+#include <gtest/gtest.h>
+
+#include <string>
+#include "TypeTraits.hpp"
+#include "Utils.hpp"
+
+namespace nb {
+
+TEST(UtilsTest, TestFindAndReplace) {
+    ASSERT_STREQ(
+        find_and_replace("Jeff", "e", "efe").c_str(), 
+        "Jefeff"
+    );
+
+    std::string tmp = find_and_replace("Naif", "a", "afa");
+    ASSERT_STREQ(
+        find_and_replace(tmp, "i", "ifi").c_str(), 
+        "Nafaifif"
+    );
+
+    tmp = find_and_replace("aeiou", "a", "afa");
+    tmp = find_and_replace(tmp, "e", "efe");
+    tmp = find_and_replace(tmp, "i", "ifi");
+    tmp = find_and_replace(tmp, "o", "ofo");
+    tmp = find_and_replace(tmp, "u", "ufu");
+    ASSERT_STREQ(
+        tmp.c_str(), 
+        "afaefeifiofoufu"
+    );
+
+    tmp = find_and_replace(tmp, "afa", "a");
+    tmp = find_and_replace(tmp, "efe", "e");
+    tmp = find_and_replace(tmp, "ifi", "i");
+    tmp = find_and_replace(tmp, "ofo", "o");
+    tmp = find_and_replace(tmp, "ufu", "u");
+    ASSERT_STREQ(
+        tmp.c_str(), 
+        "aeiou"
+    );
+}
+
+TEST(UtilsTest, TestFindAndReplaceWstr) {
+    ASSERT_STREQ(
+        find_and_replace<std::wstring>(L"Jeff", L"e", L"efe").c_str(), 
+        L"Jefeff"
+    );
+
+    std::wstring tmp = find_and_replace<std::wstring>(L"Naif", L"a", L"afa");
+    ASSERT_STREQ(
+        find_and_replace<std::wstring>(tmp, L"i", L"ifi").c_str(), 
+        L"Nafaifif"
+    );
+
+    tmp = find_and_replace<std::wstring>(L"aeiou", L"a", L"afa");
+    tmp = find_and_replace<std::wstring>(tmp, L"e", L"efe");
+    tmp = find_and_replace<std::wstring>(tmp, L"i", L"ifi");
+    tmp = find_and_replace<std::wstring>(tmp, L"o", L"ofo");
+    tmp = find_and_replace<std::wstring>(tmp, L"u", L"ufu");
+    ASSERT_STREQ(
+        tmp.c_str(), 
+        L"afaefeifiofoufu"
+    );
+
+    tmp = find_and_replace<std::wstring>(tmp, L"afa", L"a");
+    tmp = find_and_replace<std::wstring>(tmp, L"efe", L"e");
+    tmp = find_and_replace<std::wstring>(tmp, L"ifi", L"i");
+    tmp = find_and_replace<std::wstring>(tmp, L"ofo", L"o");
+    tmp = find_and_replace<std::wstring>(tmp, L"ufu", L"u");
+    ASSERT_STREQ(
+        tmp.c_str(), 
+        L"aeiou"
+    );
+}
+
+TEST(UtilsTest, TestWstrToStr) {
+    ASSERT_STREQ(
+        nb::wstr_to_str(L"Hi!").c_str(), 
+        "Hi!"
+    );
+    ASSERT_STREQ(
+        nb::wstr_to_str(L"Naif").c_str(),
+        "Naif"
+    );
+    ASSERT_STREQ(
+        nb::wstr_to_str(L"\r\r\r\n").c_str(),
+        "\r\r\r\n"
+    );
+    ASSERT_STREQ(
+        nb::wstr_to_str(L"Naif\ttalks\r\ra\t\nlot").c_str(),
+        "Naif\ttalks\r\ra\t\nlot"
+    );
+}
+
+TEST(UtilsTest, TestStrToWstr) {
+    ASSERT_STREQ(
+        nb::str_to_wstr("Hi!").c_str(), 
+        L"Hi!"
+    );
+    ASSERT_STREQ(
+        nb::str_to_wstr("Naif").c_str(),
+        L"Naif"
+    );
+    ASSERT_STREQ(
+        nb::str_to_wstr("\r\r\r\n").c_str(),
+        L"\r\r\r\n"
+    );
+    ASSERT_STREQ(
+        nb::str_to_wstr("Naif\ttalks\r\ra\t\nlot").c_str(),
+        L"Naif\ttalks\r\ra\t\nlot"
+    );
+}
+
+struct A { bool x(); };
+struct B { bool y(); };
+struct C { bool x(); bool y; };
+struct D : C {};
+
+template <typename T>
+using has_x = decltype(T::x);
+
+template <typename T>
+using has_y = decltype(T::y);
+
+TEST(UtilsTest, TestIsDetected) {
+    auto ret = is_detected<has_x, A>::value;
+    ASSERT_TRUE(ret);
+    ret = is_detected<has_y, A>::value;
+    ASSERT_FALSE(ret);
+
+    ret = is_detected<has_y, B>::value;
+    ASSERT_TRUE(ret);
+    ret = is_detected<has_x, B>::value;
+    ASSERT_FALSE(ret);
+
+    ret = is_detected<has_x, C>::value;
+    ASSERT_TRUE(ret);
+    ret = is_detected<has_y, C>::value;
+    ASSERT_TRUE(ret);
+
+    ret = is_detected<has_x, D>::value;
+    ASSERT_TRUE(ret);
+    ret = is_detected<has_y, D>::value;
+    ASSERT_TRUE(ret);
+}
+
+} // namespace nb