Add optional standalone executable directory (#2)

* add standalone executable

* update readme

* add standalone workflow

* fix path

.github/workflows/standalone.yml

@@ -0,0 +1,20 @@
+name: Standalone
+
+on: [push]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    
+    steps:
+    - uses: actions/checkout@v1
+    
+    - name: configure
+      run: cmake -Hstandalone -Bbuild
+
+    - name: build
+      run: cmake --build build
+
+    - name: run
+      run: ./build/Greeter

CMakeLists.txt

@@ -37,7 +37,6 @@ CPMAddPackage(
 
 # Note:
 # for single header libraries use `add_library(Greeter INTERFACE)` instead 
-# To create an executable use `add_executable(Greeter ${headers} ${sources})`
 add_library(Greeter ${headers} ${sources})
 
 # Note: for single header libraries use the following instead:

README.md

@@ -15,7 +15,8 @@ This template is a collection from learnings of previous projects and should all
 ## Features
 
 - Modern CMake practices
-- Suited for single header libraries and larger projects
+- Suited for single header libraries and projects of any scale
+- Separation into library and executable code
 - Integrated test suite
 - Continuous integration via [GitHub Actions](https://help.github.com/en/actions/)
 - Code coverage via [codecov](https://codecov.io)
@@ -27,22 +28,35 @@ This template is a collection from learnings of previous projects and should all
 
 ### Adjust the template to your needs
 
-- Use this repo [as a template](https://help.github.com/en/github/creating-cloning-and-archiving-repositories/creating-a-repository-from-a-template) and replace all occurrences of "Greeter" in [both](test/CMakeLists.txt) [CMakeLists.txt](CMakeLists.txt) with the name of your project
+- Use this repo [as a template](https://help.github.com/en/github/creating-cloning-and-archiving-repositories/creating-a-repository-from-a-template) and replace all occurrences of "Greeter" in the relevant CMakeLists.txt with the name of your project
 - Replace the source files with your own
 - For single-header libraries: see the comments in [CMakeLists.txt](CMakeLists.txt)
 - Add your project's codecov token to your project's github secrets under `CODECOV_TOKEN`
 - Happy coding!
 
+Remember to eventually remove any unused files, such as the standalone directory or irrelevant tests for your project.
+
+### Build and run the standalone target
+
+Use the following command to build and run the executable target.
+
+```bash
+cmake -Hstandalone -Bbuild/standalone
+cmake --build build/standalone
+./build/standalone/Greeter --help
+```
+
 ### Build and run test suite
 
 Use the following commands from the project's root directory to run the test suite.
 
 ```bash
-cmake -Htest -Bbuild
+cmake -Htest -Bbuild/test
-cmake --build build
+cmake --build build/test
-CTEST_OUTPUT_ON_FAILURE=1 cmake --build build --target test
+CTEST_OUTPUT_ON_FAILURE=1 cmake --build build/test --target test
+
 # or simply call the executable: 
-./build/GreeterTests
+./build/test/GreeterTests
 ```
 
 To collect code coverage information, run CMake with the `-DENABLE_TEST_COVERAGE=1` option.
@@ -52,11 +66,13 @@ To collect code coverage information, run CMake with the `-DENABLE_TEST_COVERAGE
 Use the following commands from the project's root directory to run clang-format (must be installed on the host system).
 
 ```bash
-cmake -Htest -Bbuild
+cmake -Htest -Bbuild/test
+
 # view changes
-cmake --build build --target format
+cmake --build build/test --target format
+
 # apply changes
-cmake --build build --target fix-format
+cmake --build build/test --target fix-format
 ```
 
 See [Format.cmake](https://github.com/TheLartians/Format.cmake) for more options.

standalone/CMakeLists.txt

@@ -0,0 +1,31 @@
+cmake_minimum_required(VERSION 3.5 FATAL_ERROR)
+
+project(GreeterStandalone
+  LANGUAGES CXX
+)
+
+# ---- Dependencies ----
+
+include(../cmake/CPM.cmake)
+
+CPMAddPackage(
+  NAME cxxopts
+  GITHUB_REPOSITORY jarro2783/cxxopts
+  VERSION 2.2.0
+  OPTIONS
+    "CXXOPTS_BUILD_EXAMPLES Off"
+    "CXXOPTS_BUILD_TESTS Off"
+)
+
+CPMAddPackage(
+  NAME Greeter
+  SOURCE_DIR ${CMAKE_CURRENT_LIST_DIR}/..
+)
+
+# ---- Create standalone executable ----
+
+file(GLOB sources ${CMAKE_CURRENT_SOURCE_DIR}/source/*.cpp)
+add_executable(GreeterStandalone ${sources})
+set_target_properties(GreeterStandalone PROPERTIES CXX_STANDARD 17 COMPILE_FLAGS "-Wall -pedantic -Wextra")
+set_target_properties(GreeterStandalone PROPERTIES OUTPUT_NAME "Greeter")
+target_link_libraries(GreeterStandalone Greeter cxxopts)

standalone/source/main.cpp

@@ -0,0 +1,46 @@
+#include <greeter.h>
+
+#include <cxxopts.hpp>
+#include <iostream>
+#include <string>
+#include <unordered_map>
+
+const std::unordered_map<std::string, greeter::LanguageCode> languages{
+    {"en", greeter::LanguageCode::EN},
+    {"de", greeter::LanguageCode::DE},
+    {"es", greeter::LanguageCode::ES},
+    {"fr", greeter::LanguageCode::FR},
+};
+
+int main(int argc, char** argv) {
+  cxxopts::Options options(argv[0], "A program to welcome the world!");
+
+  std::string language;
+  std::string name;
+
+  // clang-format off
+  options.add_options()
+    ("h,help", "Show help")
+    ("n,name", "Name to greet", cxxopts::value(name)->default_value("World"))
+    ("l,lang", "Language code to use", cxxopts::value(language)->default_value("en"))
+  ;
+  // clang-format on
+
+  auto result = options.parse(argc, argv);
+
+  if (result["help"].as<bool>()) {
+    std::cout << options.help() << std::endl;
+    return 0;
+  }
+
+  auto langIt = languages.find(language);
+  if (langIt == languages.end()) {
+    std::cout << "unknown language code: " << language << std::endl;
+    return 1;
+  }
+
+  greeter::Greeter greeter(name);
+  std::cout << greeter.greet(langIt->second) << std::endl;
+
+  return 0;
+}