configured testing framework to build the project src files into the test binary so that the functions to be tested can be called from any src file

CMakeLists.txt

@@ -1,4 +1,4 @@
-# Require a modern version of CMake
+# Require a modern version of CMake 
 cmake_minimum_required(VERSION 3.15)
 
 # Define the workspace/project
@@ -22,50 +22,40 @@ set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/bin/${OUTPUT_DIR_SUFFIX}
 # ------------------------------------------------------------------------------
 # Dependencies
 # ------------------------------------------------------------------------------
-
 # 1. SDL3
-# Disable tests and examples before adding the subdirectory
 set(SDL_TESTS OFF CACHE BOOL "Disable SDL3 tests" FORCE)
 set(SDL_EXAMPLES OFF CACHE BOOL "Disable SDL3 examples" FORCE)
 add_subdirectory(libs/sdl3)
 
 # 2. spdlog
-# Force compiled mode instead of header-only, and disable extras
 set(SPDLOG_BUILD_COMPILED ON CACHE BOOL "Build spdlog as a compiled library" FORCE)
 set(SPDLOG_BUILD_EXAMPLE OFF CACHE BOOL "Disable spdlog examples" FORCE)
 set(SPDLOG_BUILD_TESTS OFF CACHE BOOL "Disable spdlog tests" FORCE)
 add_subdirectory(libs/spdlog)
 
 # 3. ImGui & ImGui Node Editor
-# Assuming you have CMakeLists.txt inside these directories.
-# If you don't, you would use add_library() to compile their .cpp files manually here.
 add_subdirectory(libs/imgui)
 add_subdirectory(libs/imgui-node-editor)
 
 # 4. Catch2
-# Testing framework
 add_subdirectory(libs/catch2)
-# These tests can use the Catch2-provided main
-add_executable(tests SakuraVNE/test/test.cpp)
-target_link_libraries(tests PRIVATE Catch2::Catch2WithMain)
 
-# These tests need their own main
-# add_executable(custom-main-tests test.cpp test-main.cpp)
-# target_link_libraries(custom-main-tests PRIVATE Catch2::Catch2)
+
+# ------------------------------------------------------------------------------
+# Source Gathering
+# ------------------------------------------------------------------------------
+# Gather all .cpp and .h files in the src folder
+file(GLOB_RECURSE SAKURA_SRCS "SakuraVNE/src/*.cpp" "SakuraVNE/src/*.h")
+
+# CRITICAL: Remove main.cpp from the list so Catch2 can provide its own main()
+list(REMOVE_ITEM SAKURA_SRCS "${CMAKE_CURRENT_SOURCE_DIR}/SakuraVNE/src/main.cpp")
+
 
 # ------------------------------------------------------------------------------
 # SakuraVNE Executable Target
 # ------------------------------------------------------------------------------
-
-# Gather all .cpp and .h files in the src folder
-file(GLOB_RECURSE SAKURA_SRCS "SakuraVNE/src/*.cpp" "SakuraVNE/src/*.h")
-
-# Create the ConsoleApp executable
-add_executable(SakuraVNE ${SAKURA_SRCS})
-
-# ------------------------------------------------------------------------------
-# Include Directories & Linking
-# ------------------------------------------------------------------------------
+# Create the ConsoleApp executable (explicitly adding main.cpp back in here)
+add_executable(SakuraVNE "SakuraVNE/src/main.cpp" ${SAKURA_SRCS})
 
 # Tell the compiler where the headers are
 target_include_directories(SakuraVNE PRIVATE
@@ -78,36 +68,72 @@ target_include_directories(SakuraVNE PRIVATE
     "libs/sdl3/include"
 )
 
-# Link the libraries. CMake handles all the libdirs automatically!
+# Link the libraries. CMake handles all the libdirs automatically! [cite: 5]
 target_link_libraries(SakuraVNE PRIVATE
-    ImGui               # (Depends on what your ImGui target is actually named)
-    ImGuiNodeEditor     # (Depends on what your ImGuiNodeEditor target is actually named)
-    SDL3::SDL3          # The official SDL3 target name
-    spdlog::spdlog      # The official spdlog target name
+    ImGui               
+    ImGuiNodeEditor     
+    SDL3::SDL3          
+    spdlog::spdlog      
 )
 
+
+# ------------------------------------------------------------------------------
+# Tests Executable Target
+# ------------------------------------------------------------------------------
+# These tests can use the Catch2-provided main, plus ALL your engine source files
+add_executable(tests "SakuraVNE/test/test.cpp" ${SAKURA_SRCS})
+
+# The tests need the exact same include directories so your engine #includes work
+target_include_directories(tests PRIVATE
+    "SakuraVNE/src"
+    "libs/spdlog/include"
+    "libs/imgui"
+    "libs/imgui/misc"
+    "libs/imgui/backends"
+    "libs/imgui-node-editor"
+    "libs/sdl3/include"
+)
+
+# Link Catch2 AND the exact same dependencies your game uses
+target_link_libraries(tests PRIVATE 
+    Catch2::Catch2WithMain
+    ImGui               
+    ImGuiNodeEditor     
+    SDL3::SDL3          
+    spdlog::spdlog 
+)
+
+
 # ------------------------------------------------------------------------------
 # Platform & Configuration Filters
 # ------------------------------------------------------------------------------
-
-# Windows-specific settings
 if(WIN32)
+    # Apply to Game
     target_compile_definitions(SakuraVNE PRIVATE PLATFORM_WINDOWS)
-    
-    # Ignore MSVCRT default library
     target_link_options(SakuraVNE PRIVATE "/NODEFAULTLIB:MSVCRT")
-
-# Linux-specific settings
-elseif(UNIX AND NOT APPLE)
-    target_compile_definitions(SakuraVNE PRIVATE PLATFORM_LINUX)
     
-    # Link dl and pthread
+    # Apply to Tests
+    target_compile_definitions(tests PRIVATE PLATFORM_WINDOWS)
+    target_link_options(tests PRIVATE "/NODEFAULTLIB:MSVCRT")
+
+elseif(UNIX AND NOT APPLE)
+    # Apply to Game
+    target_compile_definitions(SakuraVNE PRIVATE PLATFORM_LINUX)
     target_link_libraries(SakuraVNE PRIVATE dl pthread)
+    
+    # Apply to Tests
+    target_compile_definitions(tests PRIVATE PLATFORM_LINUX)
+    target_link_libraries(tests PRIVATE dl pthread)
 endif()
 
-# Debug vs Release definitions
-# $<CONFIG:...> is a generator expression that injects the flag based on the active build type
+# Debug vs Release definitions for Game
 target_compile_definitions(SakuraVNE PRIVATE
     $<$<CONFIG:Debug>:DEBUG>
     $<$<CONFIG:Release>:RELEASE>
 )
+
+# Debug vs Release definitions for Tests
+target_compile_definitions(tests PRIVATE
+    $<$<CONFIG:Debug>:DEBUG>
+    $<$<CONFIG:Release>:RELEASE>
+)

SakuraVNE/src/factorial.cpp

@@ -0,0 +1,3 @@
+#include "factorial.h"
+
+unsigned int Factorial(unsigned int number) { return number >= 1 ? Factorial(number - 1) * number : 1; }

SakuraVNE/src/factorial.h

@@ -0,0 +1 @@
+unsigned int Factorial(unsigned int number);

SakuraVNE/test/test.cpp

@@ -1 +1,10 @@
+#include "factorial.h"
+#include <catch2/catch_test_macros.hpp>
 
+TEST_CASE("Factorials are computed", "[factorial]") {
+    REQUIRE(Factorial(0) == 1);
+    REQUIRE(Factorial(1) == 1);
+    REQUIRE(Factorial(2) == 2);
+    REQUIRE(Factorial(3) == 6);
+    REQUIRE(Factorial(10) == 3628800);
+}