Rework cmake variables and defaults. (#13)

- C Lua is the default rather then C++ Lua
- Turn off test by default
- Rename cmake control variables and prepend LUABIND
- Reword and simplify readme.

CMakeLists.txt

@@ -2,42 +2,38 @@ cmake_minimum_required(VERSION 3.21)
 
 project(luabind)
 
-set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
-
 set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
-# variable to use custom library
-set(LUA_LIB_NAME luabind_lua CACHE STRING "lua library name")
-
-# variable to include tests to build phase
-set(LUABIND_TEST ON CACHE BOOL "variable to determine whether tests are included in build phase or not")
+set(LUABIND_LUA_LIB_NAME luabind_lua CACHE STRING "CMake name of lua library, luabind should be linked with.")
+set(LUABIND_LUA_CPP OFF CACHE BOOL "Whether lua was compiled as C++ and headers should be included without extern 'C'.")
 
-option(CODE_COVERAGE "Enable coverage reporting" OFF)
+option(LUABIND_TESTS "Enable tests." OFF)
+option(LUABIND_CODE_COVERAGE "Enable coverage reporting in tests" OFF)
 
 add_subdirectory(third_party)
 
 add_library(luabind INTERFACE)
 target_include_directories(luabind INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}/include)
-target_link_libraries(luabind INTERFACE ${LUA_LIB_NAME})
+target_link_libraries(luabind INTERFACE ${LUABIND_LUA_LIB_NAME})
 
-set(INCLUDE_LUA_LIB_WITH_EXTERN_C ON CACHE BOOL "flag to determine whether lua library is included with extern 'C'")
-if(INCLUDE_LUA_LIB_WITH_EXTERN_C)
-    add_compile_definitions(INCLUDE_LUA_LIB_WITH_EXTERN_C)
-    target_compile_definitions(luabind INTERFACE INCLUDE_LUA_LIB_WITH_EXTERN_C)
-endif(INCLUDE_LUA_LIB_WITH_EXTERN_C)
+if(LUABIND_LUA_CPP)
+    add_compile_definitions(LUABIND_LUA_CPP)
+    target_compile_definitions(luabind INTERFACE LUABIND_LUA_CPP)
+endif(LUABIND_LUA_CPP)
 
-if(LUABIND_TEST)
+if(LUABIND_TESTS)
     target_compile_options(luabind INTERFACE -Wall -Wextra -Wnewline-eof -Wformat -Werror)
 
-    if(CODE_COVERAGE)
+    if(LUABIND_CODE_COVERAGE)
         # Add required flags (GCC & LLVM/Clang)
         target_compile_options(luabind INTERFACE
             -O0        # no optimization
             -g         # generate debug info
             --coverage # sets all required flags
         )
         target_link_options(luabind INTERFACE --coverage)
-    endif(CODE_COVERAGE)
+    endif(LUABIND_CODE_COVERAGE)
 
     enable_testing()
     add_subdirectory(tests)

CMakePresets.json

@@ -2,7 +2,7 @@
   "version": 3,
   "cmakeMinimumRequired": {
     "major": 3,
-    "minor": 19,
+    "minor": 21,
     "patch": 0
   },
   "configurePresets": [
@@ -14,10 +14,7 @@
       "binaryDir": "${sourceDir}/build",
       "cacheVariables": {
         "CMAKE_BUILD_TYPE": "Debug",
-        "CMAKE_EXPORT_COMPILE_COMMANDS": "ON",
-        "INCLUDE_LUA_LIB_WITH_EXTERN_C": "ON",
-        "LUABIND_TEST": "ON",
-        "LUA_LIB_NAME": "luabind_lua"
+        "LUABIND_TESTS": "ON"
       }
     }
   ],

README.md

@@ -1,6 +1,8 @@
 ## Introduction
 Luabind is a small header only library aiming to provide easy means to expose C++ functionality in Lua.
-Currently it supports inheritance, binding of class member functions, member variables and global functions.
+Currently it supports inheritance, binding of class member functions, static functions, member variables and global functions.
+
+It uses variadic template magic to generate code for you, which handles function arguments transition from Lua to C++, function call, and transition result back to Lua.
 
 ## Example
 ```cpp
@@ -11,19 +13,22 @@ public:
     void credit(int amount);
     void debit(int amount);
 
-private:
+public: // public for demonstative purposes
     int balance;
 };
 
 class SpecialAccount : public Account {
 public:
     SpecialAccount(int balance, int overdraft);
 
+    int getOverdraft() const;
+
 private:
     int overdraft;
 };
 ```
 
+Binding to lua
 ```cpp
 lua_State* L = luaL_newstate();
 luaL_openlibs(L);
@@ -35,17 +40,20 @@ luabind::class_<Account>(L, "Account")
 
 luabind::class_<SpecialAccount, Account>(L, "SpecialAccount")
     .constructor<int, int>("new")
-    .property_readonly<&SpecialAccount::overdraft>("overdraft");
+    .construct_shared<int, int>("create")
+    .property_readonly<&SpecialAccount::getOverdraft>("overdraft");
 
 luaL_dostring(L, R"--(
     a = Account:new(10)
     a:credit(3)
     a:debit(2)
-    s = SpecialAccount:new(50, 10)
+    s = SpecialAccount:new(50, 10) " Memory is allocated on lua stack.
+    s:credit(20)
+    s = SpecialAccount:create(50, 10) " Represented by C++ shared_ptr on lua stack.
     s:credit(20)
 )--");
 ```
-## How to install, confugure, build and run
+## How to install, configure, build and run
 
 Ordinary prcedure when developing and testing `luabind` library.
 
@@ -61,44 +69,21 @@ cmake --build --preset luabind
 ctest --preset unit_tests
 ```
 
-There are some specifications when you want to use `luabind` as submodule. As a library it consist of submodules such as: `lua` and `googletest`. You can encounter to issues like `'multiple definition of googletest'` etc.. To avoid this conflicts on CMake level variables are defined to prevent such problems. 
-
-| CMake variable | Purpose |
-| ------ | ------ |
-| LUA_LIB_NAME (STRING) | variable to link specific library (luabind_lua is set as default) |
-| INCLUDE_LUA_LIB_WITH_EXTERN_C (BOOL) | variable to add/remove extern "C" when including lua headers |
-| LUABIND_TEST (BOOL) | variable for inclusion/exclusion of test into build phase |
+## Integrate to CMake project
 
-
-## Command line build steps
-
-- To use custom `lua` library one can run with the following command.
-```sh
-cmake --preset luabind -DLUA_LIB_NAME=[your-custom-lua-library]
-```
-> Note: `-DLUA_LIB_NAME=luabind_lua` is set by default.
-
-- To exclude `luabind` tests and `googletest` library from build phase run the following command.
-```sh
-cmake --preset luabind -DLUABIND_TEST=OFF
-```
-> Note: `-DLUABIND_TEST=ON` is set by default.
-
-- To wrap/unwrap lua includes with `extern "C"` use the variable to do so.
-```sh
-cmake --preset luabind -DINCLUDE_LUA_LIB_WITH_EXTERN_C=OFF
-```
-> Note: `-DINCLUDE_LUA_LIB_WITH_EXTERN_C=ON` is set by default.
-
-## Integrate to CMake
-
-In this example `luabind` is used as submodule.
-```
-    set(INCLUDE_LUA_LIB_WITH_EXTERN_C ON)
-    set(LUA_LIB_NAME lua)
-    set(LUABIND_TEST OFF)
-
-    add_subdirectory(luabind)
+Simple example to use `luabind` as a submodule to a project which already has Lua integrated.
+``` cmake
+# Given that "lua" is the cmake name of Lua library in the top project
+# And it has lua's path added to include path, such as:
+# target_include_directories(lua SYSTEM INTERFACE ${LUA_SOURCE_DIR})
+set(LUABIND_LUA_LIB_NAME lua)
+add_subdirectory(luabind)
 ```
 
+Here are some control variables, which will help to fine tune integration:
 
+| CMake variable | Description |
+| ------ | ------ |
+| LUABIND_LUA_LIB_NAME (STRING) | cmake name of the Lua library to use (default: luabind_lua) |
+| LUABIND_LUA_CPP (BOOL) | option indicating whether Lua headers should be included as C++ code. (default: OFF) |
+| LUABIND_TESTS (BOOL) | option to enable luabind tests (default: OFF) |

include/luabind/lua.hpp

@@ -1,16 +1,16 @@
 #ifndef LUABIND_LUA_HPP
 #define LUABIND_LUA_HPP
 
-#ifdef INCLUDE_LUA_LIB_WITH_EXTERN_C
+#ifndef LUABIND_LUA_CPP
 extern "C" {
-#endif // INCLUDE_LUA_LIB_WITH_EXTERN_C
+#endif // LUABIND_LUA_CPP
 
 #include <lua.h>
 #include <lauxlib.h>
 #include <lualib.h>
 
-#ifdef INCLUDE_LUA_LIB_WITH_EXTERN_C
+#ifndef LUABIND_LUA_CPP
 }
-#endif // INCLUDE_LUA_LIB_WITH_EXTERN_C
+#endif // LUABIND_LUA_CPP
 
 #endif // LUABIND_LUA_HPP

tests/CMakeLists.txt

@@ -1,28 +1,27 @@
-
 include(CTest)
 
 add_executable(base_class_binding base_class_binding.cpp lua_test.hpp)
-target_link_libraries(base_class_binding luabind ${LUA_LIB_NAME} gtest_main)
+target_link_libraries(base_class_binding luabind gtest_main)
 add_test(NAME base_class_binding_test COMMAND base_class_binding)
 
 add_executable(binding binding.cpp lua_test.hpp)
-target_link_libraries(binding luabind ${LUA_LIB_NAME} gtest_main)
+target_link_libraries(binding luabind gtest_main)
 add_test(NAME binding_test COMMAND binding)
 
 add_executable(const_binding const_binding.cpp lua_test.hpp)
-target_link_libraries(const_binding luabind ${LUA_LIB_NAME} gtest_main)
+target_link_libraries(const_binding luabind gtest_main)
 add_test(NAME const_binding_test COMMAND const_binding)
 
 add_executable(explicit_delete explicit_delete.cpp lua_test.hpp)
-target_link_libraries(explicit_delete luabind ${LUA_LIB_NAME} gtest_main)
+target_link_libraries(explicit_delete luabind gtest_main)
 add_test(NAME explicit_delete_test COMMAND explicit_delete)
 
 add_executable(custom_functions custom_functions.cpp lua_test.hpp)
-target_link_libraries(custom_functions luabind ${LUA_LIB_NAME} gtest_main)
+target_link_libraries(custom_functions luabind gtest_main)
 add_test(NAME custom_functions_test COMMAND custom_functions)
 
 add_executable(errors errors.cpp lua_test.hpp)
-target_link_libraries(errors luabind ${LUA_LIB_NAME} gtest_main)
+target_link_libraries(errors luabind gtest_main)
 add_test(NAME errors_test COMMAND errors)
 
 

third_party/CMakeLists.txt

@@ -1,7 +1,7 @@
-if(${LUA_LIB_NAME} STREQUAL luabind_lua)
+if(${LUABIND_LUA_LIB_NAME} STREQUAL luabind_lua)
     add_subdirectory(lua)
 endif()
 
-if(LUABIND_TEST)
+if(LUABIND_TESTS)
     add_subdirectory(googletest)
 endif()

third_party/lua/CMakeLists.txt

@@ -1,12 +1,7 @@
 set(LUA_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/lua)
 
-file(GLOB luabind_lua_header_files ${LUA_SOURCE_DIR}/*.h)
-file(GLOB luabind_lua_sources ${LUA_SOURCE_DIR}/*.c)
-list(REMOVE_ITEM luabind_lua_sources "${LUA_SOURCE_DIR}/lua.c" "${LUA_SOURCE_DIR}/luac.c" "${LUA_SOURCE_DIR}/onelua.c"  "${LUA_SOURCE_DIR}/ltests.c")
+file(GLOB LUABIND_LUA_SOURCES ${LUA_SOURCE_DIR}/*.c)
+list(REMOVE_ITEM LUABIND_LUA_SOURCES "${LUA_SOURCE_DIR}/lua.c" "${LUA_SOURCE_DIR}/luac.c" "${LUA_SOURCE_DIR}/onelua.c"  "${LUA_SOURCE_DIR}/ltests.c")
 
-add_library(luabind_lua_headers INTERFACE ${luabind_lua_header_files})
-add_library(luabind_lua STATIC ${luabind_lua_sources})
-
-target_include_directories(luabind_lua_headers SYSTEM INTERFACE ${LUA_SOURCE_DIR})
-
-target_link_libraries(luabind_lua PUBLIC luabind_lua_headers)
+add_library(luabind_lua STATIC ${LUABIND_LUA_SOURCES})
+target_include_directories(luabind_lua SYSTEM INTERFACE ${LUA_SOURCE_DIR})