CWG-10 Skeleton C++.

.clang-format

+BasedOnStyle: LLVM
+Standard: c++17

.clang-tidy

+Checks: '-*,clang-diagnostic-*,llvm-*,misc-*,-misc-const-correctness,-misc-unused-parameters,-misc-non-private-member-variables-in-classes,-misc-no-recursion,readability-identifier-naming'
+CheckOptions:
+  - key:             readability-identifier-naming.ClassCase
+    value:           CamelCase
+  - key:             readability-identifier-naming.EnumCase
+    value:           CamelCase
+  - key:             readability-identifier-naming.FunctionCase
+    value:           camelBack
+  - key:             readability-identifier-naming.MemberCase
+    value:           CamelCase
+  - key:             readability-identifier-naming.ParameterCase
+    value:           CamelCase
+  - key:             readability-identifier-naming.UnionCase
+    value:           CamelCase
+  - key:             readability-identifier-naming.VariableCase
+    value:           CamelCase

.gitignore

+build/

.gitlab-ci.common.yml

+# Copyright (C) ASTRON (Netherlands Institute for Radio Astronomy)
+# SPDX-License-Identifier: Apache-2.0
+
+workflow:
+  rules:
+    # Don't create a pipeline if it's a commit pipeline on a branch and that branch has open merge requests
+    - if: $CI_PIPELINE_SOURCE == "push" && $CI_COMMIT_BRANCH && $CI_OPEN_MERGE_REQUESTS
+      when: never
+    - when: always
+
+# Set to 1 to force a rebuild of the Docker image
+variables:
+  BUILD_DOCKER_IMAGE: "0"
+
+stages:
+  - versioning
+  - prepare
+  - linting
+  - build
+  - test
+  - pages
+
+# This step determines the SHA1 of the Docker file used. It's stored in
+# versions.env artifact. The environment variables are available for all steps
+# depending on this step.
+versioning:
+  stage: versioning
+  image: bitnami/git
+  script:
+    - echo BASE_IMAGE=${CI_REGISTRY_IMAGE}/base:$(git log -n 1 --pretty=format:%H -- ci/ubuntu_22_04-base) > versions.env
+    - cat versions.env
+  artifacts:
+    reports:
+      dotenv: versions.env
+
+# Builds the Docker image containing the dependencies of the application.
+# This image is cached, as long as the Dockerfile isn't modified new jobs reuse
+# this image.
+build-docker-ubuntu-22.04:
+  stage: prepare
+  needs: ["versioning"]
+  image: docker:latest
+  script:
+    - |
+      if ! docker manifest inspect $BASE_IMAGE > /dev/null || [ "$BUILD_DOCKER_IMAGE" = "1" ]; then
+        docker build --tag $BASE_IMAGE -f ci/ubuntu_22_04-base .
+        docker push $BASE_IMAGE
+      fi
+  before_script:
+    - echo $CI_REGISTRY_PASSWORD | docker login -u $CI_REGISTRY_USER --password-stdin $CI_REGISTRY
+
+

.gitlab-ci.yml

+# Copyright (C) ASTRON (Netherlands Institute for Radio Astronomy)
+# SPDX-License-Identifier: Apache-2.0
+
+include: .gitlab-ci.common.yml
+
+lint:
+  stage: linting
+  needs: ["versioning", "build-docker-ubuntu-22.04"]
+  image: $BASE_IMAGE
+  script:
+    - scripts/format-cpp.sh
+    - scripts/format-cmake.sh
+    - git diff > format.patch
+    # Fail when the patch is not empy (note ! can't be used directly.)
+    - (! grep -q '^--- a'  format.patch)
+    - mkdir build
+    - cd build
+    - cmake -DCMAKE_CXX_CLANG_TIDY=clang-tidy -G Ninja ..
+    - ninja
+  artifacts:
+    paths:
+      - format.patch
+
+test:
+  stage: test
+  needs: ["versioning", "build-docker-ubuntu-22.04"]
+  image: $BASE_IMAGE
+  script:
+    - mkdir build
+    - cd build
+    - cmake -DCMAKE_BUILD_TYPE=Debug -DBUILD_TESTINDBUILD_TESTSG=ON -DCMAKE_CXX_FLAGS="-coverage" -DCMAKE_EXE_LINKER_FLAGS="-coverage" -G Ninja ..
+    - ninja
+    - ctest --output-on-failure |& tee ctest.out
+    - mkdir coverage
+    - gcovr -r .. -e ../test/ -e ../src/main.cpp --txt --xml coverage.xml --html-details coverage/coverage.html
+    - tar cfz coverage.tar.gz coverage/
+  artifacts:
+    paths:
+      # This will give a warning which is ok
+      - build/test/unittests.xml
+      - build/coverage.tar.gz
+    reports:
+      junit: build/test/unittests.xml
+      coverage_report:
+        coverage_format: cobertura
+        path: build/coverage.xml
+
+build:
+  stage: build
+  needs: ["versioning", "build-docker-ubuntu-22.04"]
+  image: $BASE_IMAGE
+  script:
+    - mkdir build
+    - cd build
+    - cmake -DCMAKE_BUILD_TYPE=Release -G Ninja ..
+    - ninja
+
+pages:
+  stage: pages
+  needs: ["versioning", "build-docker-ubuntu-22.04"]
+  image: $BASE_IMAGE
+  script:
+    - mkdir build
+    - cd build
+    - cmake -DBUILD_DOCUMENTATION=ON -G Ninja ..
+    - ninja sphinx

CMakeLists.txt

+cmake_minimum_required(VERSION 3.16)
+
+project(CPP VERSION 0.1)
+
+include(CheckCXXCompilerFlag)
+
+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)
+
+add_subdirectory(src)
+if(BUILD_TESTING)
+  include(CTest)
+  add_subdirectory(test)
+endif()
+
+if(BUILD_DOCUMENTATION)
+  add_subdirectory(doc)
+endif()

LICENSE

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+                           Version 2.0, January 2004
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+
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+
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README.md

 # C++ project
 
-An example repository of an CI/CD pipeline for building, testing and deploying a C++ project
-
-## Getting started
-
-To make it easy for you to get started with GitLab, here's a list of recommended next steps.
-
-Already a pro? Just edit this README.md and make it your own. Want to make it easy? [Use the template at the bottom](#editing-this-readme)!
-
-## Add your files
-
-- [ ] [Create](https://docs.gitlab.com/ee/user/project/repository/web_editor.html#create-a-file) or [upload](https://docs.gitlab.com/ee/user/project/repository/web_editor.html#upload-a-file) files
-- [ ] [Add files using the command line](https://docs.gitlab.com/ee/gitlab-basics/add-file.html#add-a-file-using-the-command-line) or push an existing Git repository with the following command:
-
-```
-cd existing_repo
-git remote add origin https://git.astron.nl/templates/cpp-project.git
-git branch -M main
-git push -uf origin main
-```
-
-## Integrate with your tools
-
-- [ ] [Set up project integrations](https://git.astron.nl/templates/cpp-project/-/settings/integrations)
-
-## Collaborate with your team
-
-- [ ] [Invite team members and collaborators](https://docs.gitlab.com/ee/user/project/members/)
-- [ ] [Create a new merge request](https://docs.gitlab.com/ee/user/project/merge_requests/creating_merge_requests.html)
-- [ ] [Automatically close issues from merge requests](https://docs.gitlab.com/ee/user/project/issues/managing_issues.html#closing-issues-automatically)
-- [ ] [Enable merge request approvals](https://docs.gitlab.com/ee/user/project/merge_requests/approvals/)
-- [ ] [Automatically merge when pipeline succeeds](https://docs.gitlab.com/ee/user/project/merge_requests/merge_when_pipeline_succeeds.html)
-
-## Test and Deploy
-
-Use the built-in continuous integration in GitLab.
-
-- [ ] [Get started with GitLab CI/CD](https://docs.gitlab.com/ee/ci/quick_start/index.html)
-- [ ] [Analyze your code for known vulnerabilities with Static Application Security Testing(SAST)](https://docs.gitlab.com/ee/user/application_security/sast/)
-- [ ] [Deploy to Kubernetes, Amazon EC2, or Amazon ECS using Auto Deploy](https://docs.gitlab.com/ee/topics/autodevops/requirements.html)
-- [ ] [Use pull-based deployments for improved Kubernetes management](https://docs.gitlab.com/ee/user/clusters/agent/)
-- [ ] [Set up protected environments](https://docs.gitlab.com/ee/ci/environments/protected_environments.html)
-
-***
-
-# Editing this README
-
-When you're ready to make this README your own, just edit this file and use the handy template below (or feel free to structure it however you want - this is just a starting point!). Thank you to [makeareadme.com](https://www.makeareadme.com/) for this template.
-
-## Suggestions for a good README
-Every project is different, so consider which of these sections apply to yours. The sections used in the template are suggestions for most open source projects. Also keep in mind that while a README can be too long and detailed, too long is better than too short. If you think your README is too long, consider utilizing another form of documentation rather than cutting out information.
-
-## Name
-Choose a self-explaining name for your project.
+An example repository of an CI/CD pipeline for building, testing and deploying a C++ project.
 
 ## Description
-Let people know what your project can do specifically. Provide context and add a link to any reference visitors might be unfamiliar with. A list of Features or a Background subsection can also be added here. If there are alternatives to your project, this is a good place to list differentiating factors.
 
-## Badges
-On some READMEs, you may see small images that convey metadata, such as whether or not all the tests are passing for the project. You can use Shields to add some to your README. Many services also have instructions for adding a badge.
+The repository can be used as a basis for new projects using C++ within ASTRON.
+The code is intended to be copied in a new repository and used as basis for the
+new project. After copying the code needs to be adjusted for the specific
+project. The template offers:
 
-## Visuals
-Depending on what you are making, it can be a good idea to include screenshots or even a video (you'll frequently see GIFs rather than actual videos). Tools like ttygif can help, but check out Asciinema for a more sophisticated method.
+- CI jobs for building, testing, and generating documentation
 
-## Installation
-Within a particular ecosystem, there may be a common way of installing things, such as using Yarn, NuGet, or Homebrew. However, consider the possibility that whoever is reading your README is a novice and would like more guidance. Listing specific steps helps remove ambiguity and gets people to using your project as quickly as possible. If it only runs in a specific context like a particular programming language version or operating system or has dependencies that have to be installed manually, also add a Requirements subsection.
+  - A basic Docker file to be used in the CI
+  - A CMake project skeleton
+  - A Doxygen and Sphinx skeleton for documentation
+  - Formatting scripts for the code
 
-## Usage
-Use examples liberally, and show the expected output if you can. It's helpful to have inline the smallest example of usage that you can demonstrate, while providing links to more sophisticated examples if they are too long to reasonably include in the README.
+Note: The project is intended to be used for C++ projects without Fortran code.
+At the moment of writing there is no Fortran support for Ninja. This means the
+project needs to be changed to use `make`.
 
-## Support
-Tell people where they can go to for help. It can be any combination of an issue tracker, a chat room, an email address, etc.
+## Getting started
 
-## Roadmap
-If you have ideas for releases in the future, it is a good idea to list them in the README.
+- Clone the project in the directory `$repo`
+- Install all dependencies as listed in `ci/ubuntu_22_04-base`
+- Create the project: `cmake -DBUILD_TESTING=ON -H$repo -B$repo/build -G Ninja`
+- Build the project: `ninja -C $repo/build`
 
 ## Contributing
-State if you are open to contributions and what your requirements are for accepting them.
-
-For people who want to make changes to your project, it's helpful to have some documentation on how to get started. Perhaps there is a script that they should run or some environment variables that they need to set. Make these steps explicit. These instructions could also be useful to your future self.
 
-You can also document commands to lint the code or run tests. These steps help to ensure high code quality and reduce the likelihood that the changes inadvertently break something. Having instructions for running tests is especially helpful if it requires external setup, such as starting a Selenium server for testing in a browser.
-
-## Authors and acknowledgment
-Show your appreciation to those who have contributed to the project.
+To contribute, please create a feature branch and a "Draft" merge request. Upon
+completion, the merge request should be marked as ready and a reviewer should be
+assigned.
 
 ## License
-For open source projects, say how it is licensed.
-
-## Project status
-If you have run out of energy or time for your project, put a note at the top of the README saying that development has slowed down or stopped completely. Someone may choose to fork your project or volunteer to step in as a maintainer or owner, allowing your project to keep going. You can also make an explicit request for maintainers.
+This project is licensed under the Apache License Version 2.0.

ci/ubuntu_22_04-base

+FROM ubuntu:22.04
+
+# This Docker image builds the dependencies for the application.
+# It lives on the head of its dependencies.
+
+# Install all build-time dependencies
+RUN export DEBIAN_FRONTEND=noninteractive && \
+	apt-get update && \
+	apt-get install -y \
+		build-essential \
+		clang-format \
+		clang-tidy \
+		cmake \
+		cmake-format \
+		doxygen \
+		gcovr \
+		git \
+		graphviz \
+		libboost-test-dev \
+		ninja-build \
+		python3-breathe \
+	&& \
+	rm -rf /var/lib/apt/lists/*

cmake/FindSphinx.cmake

+# CMake find_package() Module for Sphinx documentation generator
+# http://sphinx-doc.org/
+#
+# Example usage:
+#
+# find_package(Sphinx)
+#
+# If successful the following variables will be defined SPHINX_FOUND
+# SPHINX_EXECUTABLE
+
+find_program(
+  SPHINX_EXECUTABLE
+  NAMES sphinx-build sphinx-build2
+  DOC "Path to sphinx-build executable")
+
+# Handle REQUIRED and QUIET arguments this will also set SPHINX_FOUND to true if
+# SPHINX_EXECUTABLE exists
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(
+  Sphinx "Failed to locate sphinx-build executable" SPHINX_EXECUTABLE)
+
+# Provide options for controlling different types of output
+option(SPHINX_OUTPUT_HTML "Output standalone HTML files" ON)
+option(SPHINX_OUTPUT_MAN "Output man pages" ON)
+
+option(SPHINX_WARNINGS_AS_ERRORS
+       "When building documentation treat warnings as errors" ON)

doc/CMakeLists.txt

+# Copyright (C) ASTRON (Netherlands Institute for Radio Astronomy)
+# SPDX-License-Identifier: Apache-2.0
+
+find_package(Doxygen REQUIRED)
+find_package(Sphinx REQUIRED)
+
+#
+# The code is based on
+# https://devblogs.microsoft.com/cppblog/clear-functional-c-documentation-with-sphinx-breathe-doxygen-cmake/
+#
+
+#
+# Determine the public headers for the API documentation.
+#
+get_target_property(HELLO_PUBLIC_HEADER_DIR hello INTERFACE_INCLUDE_DIRECTORIES)
+file(GLOB_RECURSE HELLO_PUBLIC_HEADERS ${HELLO_PUBLIC_HEADER_DIR}/*)
+
+#
+# Configure Doxygen.
+#
+set(DOXYGEN_PROJECT_NAME ${CMAKE_PROJECT_NAME})
+set(DOXYGEN_INPUT ${HELLO_PUBLIC_HEADER_DIR})
+set(DOXYGEN_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/doxygen)
+set(DOXYGEN_INDEX_FILE ${DOXYGEN_OUTPUT_DIRECTORY}/html/index.html)
+set(DOXYFILE_IN "${CMAKE_CURRENT_SOURCE_DIR}/Doxyfile.in")
+set(DOXYFILE "${CMAKE_CURRENT_BINARY_DIR}/Doxyfile")
+configure_file(${DOXYFILE_IN} ${DOXYFILE} @ONLY)
+
+#
+# Adds Doxygen target.
+#
+add_custom_command(
+  OUTPUT ${DOXYGEN_INDEX_FILE}
+  DEPENDS ${HELLO_PUBLIC_HEADERS}
+  COMMAND ${DOXYGEN_EXECUTABLE} ${DOXYFILE_OUT}
+  MAIN_DEPENDENCY ${DOXYFILE}
+  ${DOXYFILE_IN}
+  COMMENT "Generating documentation with Doxygen")
+add_custom_target(doxygen ALL DEPENDS ${DOXYGEN_INDEX_FILE})
+
+set(SPHINX_SOURCE "${CMAKE_CURRENT_SOURCE_DIR}/sphinx")
+set(SPHINX_BUILD "${CMAKE_CURRENT_BINARY_DIR}/sphinx")
+set(SPHINX_INDEX_FILE ${SPHINX_BUILD}/index.html)
+
+# Only regenerate Sphinx when: - Doxygen has rerun - Our doc files have been
+# updated - The Sphinx config has been updated
+add_custom_command(
+  OUTPUT ${SPHINX_INDEX_FILE}
+  COMMAND
+    ${SPHINX_EXECUTABLE} -b html
+    # Tell Breathe where to find the Doxygen output
+    -Dbreathe_projects.CPP=${DOXYGEN_OUTPUT_DIRECTORY}/xml ${SPHINX_SOURCE}
+    ${SPHINX_BUILD}
+  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+  DEPENDS # Other docs files you want to track should go here (or in some
+          # variable)
+          ${SPHINX_SOURCE}/index.rst ${DOXYGEN_INDEX_FILE}
+  MAIN_DEPENDENCY ${SPHINX_SOURCE}/conf.py
+  COMMENT "Generating documentation with Sphinx")
+
+# Nice named target so we can run the job easily
+add_custom_target(sphinx ALL DEPENDS ${SPHINX_INDEX_FILE})

doc/sphinx/conf.py

+# Configuration file for the Sphinx documentation builder.
+#
+# This file only contains a selection of the most common options. For a full
+# list see the documentation:
+# https://www.sphinx-doc.org/en/master/usage/configuration.html
+
+# -- Path setup --------------------------------------------------------------
+
+# If extensions (or modules to document with autodoc) are in another directory,
+# add these directories to sys.path here. If the directory is relative to the
+# documentation root, use os.path.abspath to make it absolute, like shown here.
+#
+import os
+import sys
+
+# -- General configuration ---------------------------------------------------
+
+# Add any Sphinx extension module names here, as strings. They can be
+# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
+# ones.
+extensions = [
+    "breathe",
+]
+
+# Breathe Configuration
+breathe_default_project = "CPP"

doc/sphinx/index.rst

+…
+
+# Documentation
+# https://breathe.readthedocs.io/en/latest/directives.html
+
+Docs
+====
+
+.. doxygenfunction:: Hello

include/hello.hpp

+// Copyright (C) ASTRON (Netherlands Institute for Radio Astronomy)
+// SPDX-License-Identifier: Apache-2.0
+
+#ifndef CPP_INCLUDE_HELLO_HPP
+#define CPP_INCLUDE_HELLO_HPP
+
+namespace lib {
+
+/** This function greets the user. */
+void Hello();
+
+} // namespace lib
+
+#endif // CPP_INCLUDE_HELLO_HPP

scripts/format-cmake.sh

+#!/bin/bash
+
+set -e
+
+if [ ! $(which cmake-format) ]; then
+	echo "Please install cmake-format"
+	exit 1
+fi
+
+ROOT="$(git rev-parse --show-toplevel)"
+
+find "$ROOT" -type d -name build -prune -false -o -type f \( -name 'CMakeLists.txt' -o -name '*.cmake' \) -exec cmake-format -i \{} \;

scripts/format-cpp.sh

+#!/bin/bash
+
+set -e
+
+if [ ! $(which clang-format) ]; then
+	echo "Please install clang-format"
+	exit 1
+fi
+
+ROOT="$(git rev-parse --show-toplevel)"
+
+find "$ROOT" -type d -name build -prune -false -o -type f -name '*.[ch]pp' -exec clang-format -i \{} \;

src/CMakeLists.txt

+# Copyright (C) ASTRON (Netherlands Institute for Radio Astronomy)
+# SPDX-License-Identifier: Apache-2.0
+
+add_subdirectory(lib)
+
+add_executable(cpp main.cpp)
+
+target_link_libraries(cpp PRIVATE hello)

src/lib/CMakeLists.txt

+# Copyright (C) ASTRON (Netherlands Institute for Radio Astronomy)
+# SPDX-License-Identifier: Apache-2.0
+
+add_library(hello SHARED hello.cpp)
+
+target_include_directories(hello PUBLIC "${CMAKE_SOURCE_DIR}/include")

src/lib/hello.cpp

+// Copyright (C) ASTRON (Netherlands Institute for Radio Astronomy)
+// SPDX-License-Identifier: Apache-2.0
+
+#include "hello.hpp"
+
+#include <iostream>
+#include <string>
+
+namespace lib {
+
+void Hello() { std::cout << "Hello world\n"; }
+
+} // namespace lib