reflection.h File

C++ header file with declarations for the µTest++ reflection utilities. More...

Included Headers

#include <string_view> #include <version> #include "inlines/reflection-inlines.h"

Namespaces Index

namespace	micro_os_plus
	The primary namespace for the µOS++ framework. More...
namespace	micro_test_plus
	Primary namespace for the µTest++ testing framework. More...
namespace	reflection
	Reflection utilities for the µTest++ testing framework. More...

Classes Index

class	source_location
	Local implementation of source location information for diagnostics. More...

Functions Index

template <class T>
constexpr std::string_view	type_name (void)
	Extracts the type name from the __PRETTY_FUNCTION__ identifier. More...

Description

C++ header file with declarations for the µTest++ reflection utilities.

This header provides the declarations for the reflection utilities used within the µTest++ framework. It defines interfaces for obtaining source location information and extracting type names at compile time, for the reports of the checks.

The reflection utilities include a local implementation of source_location for standard libraries that do not yet provide std::source_location, and a function to extract concise type names using the compiler-specific __PRETTY_FUNCTION__ identifier. These facilities enable precise identification of code locations and types in test reports.

All definitions reside within the micro_os_plus::micro_test_plus::reflection namespace.

This file is included by micro-os-plus/micro-test-plus.h, which is the header that the applications include.

Functions

type_name()

template <class T>

std::string_view micro_os_plus::micro_test_plus::reflection::type_name (void)

nodiscard constexpr

Extracts the type name from the __PRETTY_FUNCTION__ identifier.

This function template parses the compiler-specific __PRETTY_FUNCTION__ identifier to extract a concise type name for the template parameter T.

Rather than relying on fixed character offsets (which are fragile across compiler versions and namespace changes), the implementation searches for the marker that introduces the template argument in the function signature string:

• Clang formats the signature as "... [T = <typename>]", so the type name lies between the first "[T = " and the last ']'. The marker is searched for as a whole, since the type name may itself contain brackets (e.g. int[3]).
• GCC formats the signature as "... [with T = <typename>]" or, on some versions, "... [with T = <typename>; ...]", so the type name starts after the first "[with T = " and ends at the following ';' or, if there is none, at the last ']'.

If the marker is not found, or the compiler is not supported (e.g. MSVC, which uses __FUNCSIG__ instead of __PRETTY_FUNCTION__), the function returns "unknown" rather than failing to compile, since the name is used only to improve the test output.

The expected layouts are verified at compile time by the static_assert checks that follow the definition.

The name is spelled as the compiler prints it, and is used to identify the expected exception type in the throws<E> failure messages. Only clang and GCC are supported; with other compilers the function returns "unknown".

Template Parameters

T	The type whose name is to be extracted.

Parameters

None.

Returns

A std::string_view containing the extracted type name, or "unknown" if it cannot be determined.

Definition at line 149 of file reflection-inlines.h.

149 type_name (void) -> std::string_view

150 {

151#if defined(__clang__)

152 // Clang: "... [T = <typename>]"

153 const std::string_view sv = __PRETTY_FUNCTION__;

154 constexpr std::string_view marker{ "[T = " };

155 const auto pos = sv.find (marker);

156 const auto end = sv.rfind (']');

157#elif defined(__GNUC__)

158 // GCC: "... [with T = <typename>]" or, on some versions,

159 // "... [with T = <typename>; std::string_view = ...]"

160 const std::string_view sv = __PRETTY_FUNCTION__;

161 constexpr std::string_view marker{ "[with T = " };

162 const auto pos = sv.find (marker);

163 const auto semi = sv.find (';', pos);

164 const auto end

165 = (semi != std::string_view::npos) ? semi : sv.rfind (']');

166#else

167 // Unsupported compiler; no portable signature string is available.

168 const std::string_view sv{};

169 constexpr std::string_view marker{};

170 const auto pos = std::string_view::npos;

171 const auto end = std::string_view::npos;

172#endif // defined(__clang__) || defined(__GNUC__)

173 if (pos == std::string_view::npos || end == std::string_view::npos

174 || end < pos + marker.size ())

175 {

176 return "unknown";

177 }

178 const auto start = pos + marker.size ();

179 return sv.substr (start, end - start);

180 }

Reference micro_os_plus::micro_test_plus::reflection::type_name.

Referenced by micro_os_plus::micro_test_plus::detail::expression_formatter::operator<< and micro_os_plus::micro_test_plus::reflection::type_name.

File Listing

The file content with the documentation metadata removed is:

1/*

2 * This file is part of the µOS++ project (https://micro-os-plus.github.io/).

3 * Copyright (c) 2021-2026 Liviu Ionescu. All rights reserved.

4 *

5 * Permission to use, copy, modify, and/or distribute this software for any

6 * purpose is hereby granted, under the terms of the MIT license.

7 *

8 * If a copy of the license was not distributed with this file, it can be

9 * obtained from https://opensource.org/licenses/mit.

10 *

11 * Major parts of the code are inspired from v1.1.8 of the Boost UT project,

12 * released under the terms of the Boost Version 1.0 Software License,

13 * which can be obtained from https://www.boost.org/LICENSE_1_0.txt.

14 */

15

16// ----------------------------------------------------------------------------

17

41

42#ifndef MICRO_OS_PLUS_MICRO_TEST_PLUS_REFLECTION_H_

43#define MICRO_OS_PLUS_MICRO_TEST_PLUS_REFLECTION_H_

44

45// ----------------------------------------------------------------------------

46

47#if defined(__cplusplus)

48

49// ----------------------------------------------------------------------------

50

51#if __has_include("micro-os-plus/project-config.h")

52#include "micro-os-plus/project-config.h"

53#endif // __has_include("micro-os-plus/project-config.h")

54

55#if __has_include("micro-os-plus/micro-test-plus-defines.h")

56#include "micro-os-plus/micro-test-plus-defines.h"

57#endif // __has_include("micro-os-plus/micro-test-plus-defines.h")

58

59#include <string_view>

60// Defines `__cpp_lib_source_location` regardless of the headers included

61// before this one, so that all translation units choose the same

62// `source_location` type.

63#include <version>

64

65#if defined(__cpp_lib_source_location)

66#include <source_location>

67#endif // defined(__cpp_lib_source_location)

68

69// ----------------------------------------------------------------------------

70

71#if defined(__GNUC__)

72#pragma GCC diagnostic push

73

74#pragma GCC diagnostic ignored "-Wpadded"

75#pragma GCC diagnostic ignored "-Waggregate-return"

76#if defined(__clang__)

77#pragma clang diagnostic ignored "-Wc++98-compat"

78#endif // defined(__clang__)

79#endif // defined(__GNUC__)

80

81// ============================================================================

82

83namespace micro_os_plus::micro_test_plus

84{

85 // --------------------------------------------------------------------------

86

101 namespace reflection

102 {

103 // ------------------------------------------------------------------------

104

105#if defined(__cpp_lib_source_location)

106

118 using source_location = std::source_location;

119

120#else

121

142 class source_location

143 {

144 public:

152 [[nodiscard]] static constexpr source_location

153 current (

154#if (__has_builtin(__builtin_FILE) and __has_builtin(__builtin_LINE))

155 const char* file = __builtin_FILE (),

156 unsigned int line = __builtin_LINE ()

157#else

158 const char* file = "unknown", unsigned int line = {}

159#endif // (__has_builtin(__builtin_FILE) and __has_builtin(__builtin_LINE))

160 ) noexcept;

161

169 [[nodiscard]] constexpr auto

170 file_name (void) const noexcept;

171

179 [[nodiscard]] constexpr auto

180 line (void) const noexcept;

181

182 private:

189 const char* file_{ "unknown" };

190

197 unsigned int line_{};

198 };

199

200#endif // defined(__cpp_lib_source_location)

201

218 template <class T>

219 [[nodiscard]] constexpr auto

220 type_name (void) -> std::string_view;

221

222 // ------------------------------------------------------------------------

223 } // namespace reflection

224

225 // --------------------------------------------------------------------------

226} // namespace micro_os_plus::micro_test_plus

227

228#if defined(__GNUC__)

229#pragma GCC diagnostic pop

230#endif // defined(__GNUC__)

231

232// ----------------------------------------------------------------------------

233

234#endif // defined(__cplusplus)

235

236// ============================================================================

237// Templates, inlines & constexpr implementations.

238

239#include "inlines/reflection-inlines.h"

240

241// ----------------------------------------------------------------------------

242

243#endif // MICRO_OS_PLUS_MICRO_TEST_PLUS_REFLECTION_H_

244

245// ----------------------------------------------------------------------------

---

Generated via doxygen2docusaurus 2.2.8 by Doxygen 1.18.0.