Support for Lua 5.4+ & C++17 (#111)

* Update checkout action on GHA CI

* Show output on test failure

* Fix test compat with C++17

* Add missing header

* Disable warning in GCC 13

* Fix compatibility with Lua 5.4

The couroutine result index is always 1, not dependent on the number of
results which is not available in < 5.4.
Errors during GC are shown as warnings in 5.4+

* Add Lua 5.4.7 to the test matrix

* Fix compatibility with Lua 5.4.4+

A change in Lua 5.4.4 resets the Lua status to OK before calling the
panic handler.
This affects a test checking for an out-of-memory exception.
Check the message string instead for something memory related which is
"good enough".

Author: Flamefire

.github/workflows/test.yml

@@ -15,7 +15,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        luaversion: [lua-5.1.5,lua-5.2.4,lua-5.3.6,lua-5.4.3]
+        luaversion: [lua-5.1.5,lua-5.2.4,lua-5.3.6,lua-5.4.3,lua-5.4.7]
       fail-fast: false
     # The CMake configure and build commands are platform agnostic and should work equally
     # well on Windows or Mac.  You can convert this to a matrix build if you need
@@ -24,7 +24,7 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Download Lua
       run: wget https://www.lua.org/ftp/${{ matrix.luaversion }}.tar.gz && tar zxf ${{ matrix.luaversion }}.tar.gz
     - name: Configure CMake
@@ -40,5 +40,5 @@ jobs:
       working-directory: ${{github.workspace}}/build
       # Execute tests defined by the CMake configuration.  
       # See https://cmake.org/cmake/help/latest/manual/ctest.1.html for more detail
-      run: ctest -C ${{env.BUILD_TYPE}}
+      run: ctest --output-on-failure -C ${{env.BUILD_TYPE}}
 

CMakeLists.txt

@@ -45,6 +45,9 @@ if(NOT MSVC)#-Wall nonsense on MSVC
   add_definitions(-pedantic)
   add_definitions(-Wno-variadic-macros)
   add_definitions ("-Wno-unused-local-typedefs")
+  if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 13)
+    add_definitions(-Wno-dangling-reference)
+  endif()
   add_definitions ("-Wno-unknown-warning-option")
   #add_definitions("-std=c++11")
 endif(NOT MSVC)

include/kaguya/detail/lua_function_def.hpp

@@ -165,8 +165,8 @@ template <typename Derived> class LuaThreadImpl {
     int nresult = 1;
     int result = lua_resume(thread, state, argnum, &nresult);
     except::checkErrorAndThrow(result, thread);
-    return detail::FunctionResultProxy::ReturnValue(thread, result, nresult - (lua_gettop(state) + 1),
-                                                    types::typetag<Result>());
+    assert(nresult == lua_gettop(thread)); // All results are on top of the thread stack
+    return detail::FunctionResultProxy::ReturnValue(thread, result, 1, types::typetag<Result>());
   }
   template <class... Args> FunctionResults operator()(Args &&... args);
 #else
@@ -197,8 +197,7 @@ template <typename Derived> class LuaThreadImpl {
     int nresult = 1;                                                           \
     int result = lua_resume(thread, state, argnum, &nresult);                  \
     except::checkErrorAndThrow(result, thread);                                \
-    return detail::FunctionResultProxy::ReturnValue(thread, result, nresult - (lua_gettop(state) + 1),  \
-                                                    types::typetag<Result>()); \
+    return detail::FunctionResultProxy::ReturnValue(thread, result, 1, types::typetag<Result>()); \
   }
 
   KAGUYA_RESUME_DEF(0)

test/test_01_primitive.cpp

@@ -1,6 +1,7 @@
 #include "kaguya/kaguya.hpp"
 #include <limits>
 #include "test_util.hpp"
+#include <limits>
 
 KAGUYA_TEST_GROUP_START(test_01_primitive)
 

test/test_04_lua_function.cpp

@@ -121,7 +121,6 @@ KAGUYA_TEST_FUNCTION_DEF(coroutine)(kaguya::State &state) {
     cor2.resume<void>(corfun, 3);
   }
   {
-
     state["cor2"] = kaguya::NewThread();
     kaguya::LuaRef cor2 = state["cor2"];
     TEST_CHECK(state("corfun = function(arg)"
@@ -137,6 +136,40 @@ KAGUYA_TEST_FUNCTION_DEF(coroutine)(kaguya::State &state) {
       yieldnum++;
     }
 
+    TEST_EQUAL(yieldnum, 10);
+  }
+  {
+    // Mix yielding and receiving params
+    state["cor3"] = kaguya::NewThread();
+    kaguya::LuaRef cor2 = state["cor3"];
+    TEST_CHECK(state("corfun = function(arg)"
+                     "for i = 1,arg do "
+                     "j, j1 = coroutine.yield() "
+                     "k = coroutine.yield(j) "
+                     "coroutine.yield(k, j1) "
+                     "end "
+                     "end"));
+    kaguya::LuaRef corfun = state["corfun"];
+    kaguya::FunctionResults res0 = cor2(corfun, 10);
+    TEST_EQUAL(res0.size(), 0u); // 1st yield
+    int yieldnum = 0;
+    while (cor2.threadStatus() == LUA_YIELD) {
+      const int j = yieldnum * 2 + 3;
+      const int j1 = j + 7;
+      int res_j = cor2(j, j1);
+      TEST_EQUAL(res_j, j)
+      const int k = j + 5;
+      const kaguya::FunctionResults res_k_j1 = cor2(k);
+      TEST_EQUAL(res_k_j1.result_size(), 2);
+      const int res_k = res_k_j1.result_at(0);
+      const int res_j1 = res_k_j1.result_at(1);
+      TEST_EQUAL(res_k, k);
+      TEST_EQUAL(res_j1, j1);
+      kaguya::FunctionResults res_empty = cor2(); // First in loop or end
+      TEST_EQUAL(res_empty.size(), 0u);
+      yieldnum++;
+    }
+
     TEST_EQUAL(yieldnum, 10);
   }
 }

test/test_06_state.cpp

@@ -366,6 +366,13 @@ KAGUYA_TEST_FUNCTION_DEF(allocation_error_test)(kaguya::State &) {
     } catch (const kaguya::LuaMemoryError &) {
       continue;
     }
+#if LUA_VERSION_RELEASE_NUM >= 50404
+    // In Lua 5.4.4+ we don't get a specific error status for Lua panics
+    catch (const kaguya::LuaUnknownError & e) {
+      if (std::string(e.what()).find("memory") != std::string::npos)
+        continue;
+    }
+#endif
     TEST_CHECK(false);
   }
 }
@@ -472,7 +479,7 @@ KAGUYA_TEST_FUNCTION_DEF(this_typemismatch_error_test)(kaguya::State &state) {
   }
 }
 
-#if LUA_VERSION_NUM >= 502
+#if LUA_VERSION_NUM >= 502 && LUA_VERSION_NUM < 504
 KAGUYA_TEST_FUNCTION_DEF(gc_error_throw_test)(kaguya::State &) {
   bool catch_except = false;
   try {

test/test_util.hpp

@@ -216,7 +216,7 @@ struct TestClass {
 };
 }
 
-#if KAGUYA_USE_CPP11
+#if KAGUYA_USE_CPP11 && (__cplusplus < 201703L)
 inline std::ostream &operator<<(std::ostream &os, std::nullptr_t) {
   return os << "nullptr";
 }