CWG-45: Implement git tag based version extraction

{{cookiecutter.project_slug}}/CMakeLists.txt

 cmake_minimum_required(VERSION 3.16)
 
-project({{cookiecutter.project_slug}} VERSION 0.1)
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 
 include(CheckCXXCompilerFlag)
+include(GitVersion)
+
+get_version_info({{cookiecutter.project_slug}} "${CMAKE_CURRENT_SOURCE_DIR}")
+set(project_slug {{cookiecutter.project_slug}})
+
+project({{cookiecutter.project_slug}} VERSION ${${project_slug}_VERSION})
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED YES)
 set(CMAKE_CXX_EXTENSIONS OFF)
 
-set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake")
-
 option(BUILD_TESTING "Build the test suite" OFF)
 option(BUILD_DOCUMENTATION "Build the documentation" OFF)
 

{{cookiecutter.project_slug}}/README.md

@@ -36,6 +36,15 @@ For instance:
 - Install the project globally: ``ninja -C ./build/ install``
 - Clean caches: `ninja -C ./build/ clean`
 
+## Versioning
+
+This project uses git tags or branch names to determine the current version of the
+software. The version information is automatically made available in CMake and can be
+made available in C/C++ by dynamically adding a generated header.
+
+See for details:
+- https://github.com/jahnf/CMake-GitVersion/blob/develop/cmake/GitVersion.cmake
+
 ## Contributing
 
 To contribute, please create a feature branch and a "Draft" merge request. Upon

{{cookiecutter.project_slug}}/cmake/ArchiveExportInfo.cmake

+# Fallback for version generation from pure git archive exports
+
+set(GIT_EXPORT_VERSION_SHORTHASH "$Format:%h$")
+set(GIT_EXPORT_VERSION_FULLHASH "$Format:%H$")
+set(GIT_EXPORT_VERSION_BRANCH "$Format:%D$") # needs parsing in cmake...
+set(HAS_GIT_EXPORT_INFO 1)

{{cookiecutter.project_slug}}/cmake/ArchiveVersionInfo.cmake.in

+# Auto generated archive version information
+# Included in created source archives
+
+set(@PREFIX@_VERSION "@VERSION@")
+set(@PREFIX@_VERSION_MAJOR "@VERSION_MAJOR@")
+set(@PREFIX@_VERSION_MINOR "@VERSION_MINOR@")
+set(@PREFIX@_VERSION_PATCH "@VERSION_PATCH@")
+set(@PREFIX@_VERSION_FLAG "@VERSION_FLAG@")
+set(@PREFIX@_VERSION_DISTANCE "@VERSION_DISTANCE@")
+set(@PREFIX@_VERSION_SHORTHASH "@VERSION_SHORTHASH@")
+set(@PREFIX@_VERSION_FULLHASH "@VERSION_FULLHASH@")
+set(@PREFIX@_VERSION_STRING "@VERSION_STRING@")
+set(@PREFIX@_VERSION_ISDIRTY "@VERSION_ISDIRTY@")
+set(@PREFIX@_VERSION_BRANCH "@VERSION_BRANCH@")
+set(@PREFIX@_VERSION_SUCCESS 1)

{{cookiecutter.project_slug}}/cmake/GitVersion.cc.in

+#include "@PREFIX@-GitVersion.h"
+
+namespace @PREFIX@ {
+  const char* version() { return "@VERSION@"; }
+  const char* version_string() { return "@VERSION_STRING@"; }
+  unsigned int version_major() { return @VERSION_MAJOR@; }
+  unsigned int version_minor() { return @VERSION_MINOR@; }
+  unsigned int version_patch() { return @VERSION_PATCH@; }
+  const char* version_flag() { return "@VERSION_FLAG@"; }
+  unsigned int version_distance() { return @VERSION_DISTANCE@; }
+  const char* version_shorthash() { return "@VERSION_SHORTHASH@"; }
+  const char* version_fullhash() { return "@VERSION_FULLHASH@"; }
+  bool version_isdirty() { return @VERSION_ISDIRTY@; }
+  const char* version_branch() { return "@VERSION_BRANCH@"; }
+}

{{cookiecutter.project_slug}}/cmake/GitVersion.h.in

+#ifndef @PREFIX@_GITVERSION_H
+#define @PREFIX@_GITVERSION_H
+
+namespace @PREFIX@ {
+  const char* version();
+  const char* version_string();
+  unsigned int version_major();
+  unsigned int version_minor();
+  unsigned int version_patch();
+  const char* version_flag();
+  unsigned int version_distance();
+  const char* version_shorthash();
+  const char* version_fullhash();
+  bool version_isdirty();
+  const char* version_branch();
+}
+
+#endif

{{cookiecutter.project_slug}}/src/CMakeLists.txt

@@ -4,5 +4,6 @@
 add_subdirectory(lib)
 
 add_executable(cpp main.cpp)
+add_version_info(TARGET cpp)
 
 target_link_libraries(cpp PRIVATE hello)

{{cookiecutter.project_slug}}/src/main.cpp

 // Copyright (C) ASTRON (Netherlands Institute for Radio Astronomy)
 // SPDX-License-Identifier: Apache-2.0
 
+#include <iostream>
+
 #include "hello.hpp"
+#include "cpp-GitVersion.h"
+
+int main(int, const char **) {
+    lib::Hello();
 
-int main(int, const char **) { lib::Hello(); }
+    std::cout << "CMake-GitVersion example"<< std::endl;
+    std::cout << "- version: " << cpp::version() << std::endl;
+    std::cout << "- version_string: " << cpp::version_string() << std::endl;
+    std::cout << "- version_branch: " << cpp::version_branch() << std::endl;
+    std::cout << "- version_fullhash: " << cpp::version_fullhash() << std::endl;
+    std::cout << "- version_shorthash: " << cpp::version_shorthash() << std::endl;
+    std::cout << "- version_isdirty: " << cpp::version_isdirty() << std::endl;
+    std::cout << "- version_distance: " << cpp::version_distance() << std::endl;
+    std::cout << "- version_flag: " << cpp::version_flag() << std::endl;
+}