CMake: XCode dependency chain fixes

When attempting to generate XCode projects it would fail due to the target dependency chain not meeting expectations.

This PR simplifies the target dependencies
And adds control over the GODOTCPP_TARGETS generated.

Author: enetheru

cmake/GodotCPPModule.cmake

@@ -107,22 +107,23 @@ function(
     # Strip newlines and whitespace to make it a one-liner.
     string(REGEX REPLACE "\n *" " " PYTHON_SCRIPT "${PYTHON_SCRIPT}")
 
-    add_custom_command(
-        OUTPUT ${GENERATED_FILES_LIST}
+    add_custom_target(
+        godot-cpp.generate_bindings
         COMMAND "${Python3_EXECUTABLE}" "-c" "${PYTHON_SCRIPT}"
-        VERBATIM
+        BYPRODUCTS ${GENERATED_FILES_LIST}
         WORKING_DIRECTORY ${godot-cpp_SOURCE_DIR}
-        MAIN_DEPENDENCY ${GODOTCPP_GDEXTENSION_API_FILE}
-        DEPENDS ${godot-cpp_SOURCE_DIR}/binding_generator.py
         COMMENT "Generating bindings"
+        VERBATIM
+        SOURCES ${godot-cpp_SOURCE_DIR}/binding_generator.py ${GODOTCPP_GDEXTENSION_API_FILE}
     )
+    set_target_properties(godot-cpp.generate_bindings PROPERTIES FOLDER "godot-cpp")
 endfunction()
 
 #[[ Generate doc_data.cpp
 The documentation displayed in the Godot editor is compiled into the extension.
 It takes a list of XML source files, and transforms them into a cpp file that
 is added to the sources list.]]
-function(generate_doc_source OUTPUT_PATH SOURCES)
+function(generate_doc_source TARGET OUTPUT_PATH SOURCES)
     # Transform SOURCES CMake LIST
     # quote each path with ''
     # join with , to transform into a python list minus the surrounding []
@@ -140,16 +141,14 @@ function(generate_doc_source OUTPUT_PATH SOURCES)
         "generate_doc_source( '${OUTPUT_PATH}', [${PYTHON_LIST}] )"
     )
 
-    add_custom_command(
-        OUTPUT "${OUTPUT_PATH}"
+    add_custom_target(
+        ${TARGET}
         COMMAND "${Python3_EXECUTABLE}" "-c" "${PYTHON_SCRIPT}"
-        VERBATIM
+        BYPRODUCTS "${OUTPUT_PATH}"
         WORKING_DIRECTORY "${godot-cpp_SOURCE_DIR}"
-        DEPENDS
-        DEPENDS #
-            "${godot-cpp_SOURCE_DIR}/doc_source_generator.py"
-            "${SOURCES}"
         COMMENT "Generating: ${OUTPUT_PATH}"
+        VERBATIM
+        SOURCES "${godot-cpp_SOURCE_DIR}/doc_source_generator.py" ${SOURCES}
     )
 endfunction()
 
@@ -164,16 +163,8 @@ function(target_doc_sources TARGET SOURCES)
 
     # Create the file generation target, this won't be triggered unless a target
     # that depends on DOC_SOURCE_FILE is built
-    generate_doc_source( "${DOC_SOURCE_FILE}" ${SOURCES} )
+    generate_doc_source( ${TARGET}_doc_gen "${DOC_SOURCE_FILE}" ${SOURCES} )
 
     # Add DOC_SOURCE_FILE as a dependency to TARGET
     target_sources(${TARGET} PRIVATE "${DOC_SOURCE_FILE}")
-
-    # Create a dummy target that depends on the source so that users can
-    # test the file generation task.
-    if(TARGET doc_gen)
-    else()
-        add_custom_target(doc_gen)
-    endif()
-    target_sources(doc_gen PRIVATE "${DOC_SOURCE_FILE}")
 endfunction()

cmake/godotcpp.cmake

@@ -110,6 +110,17 @@ function(godotcpp_options)
     #NOTE: platform is managed using toolchain files.
     #NOTE: arch is managed by using toolchain files.
     # Except for macos universal, which can be set by GODOTCPP_MACOS_UNIVERSAL=YES
+    set(GODOTCPP_VALID_TARGETS "template_debug;template_release;editor")
+    set(GODOTCPP_TARGETS
+        ${GODOTCPP_VALID_TARGETS}
+        CACHE STRING
+        "Which targets to generate, must be a semicolon separated list. valid values are: template_debug, template_release, and editor"
+    )
+    foreach(TARGET ${GODOTCPP_TARGETS})
+        if(NOT ${TARGET} IN_LIST GODOTCPP_VALID_TARGETS)
+            message(FATAL_ERROR "invalid GODOTCPP_TARGETS valid values are ${GODOTCPP_VALID_TARGETS} ")
+        endif()
+    endforeach()
 
     # Input from user for GDExtension interface header and the API JSON file
     set(GODOTCPP_GDEXTENSION_DIR
@@ -269,9 +280,6 @@ function(godotcpp_generate)
             "${CMAKE_CURRENT_BINARY_DIR}"
     )
 
-    add_custom_target(godot-cpp.generate_bindings DEPENDS ${GENERATED_FILES_LIST})
-    set_target_properties(godot-cpp.generate_bindings PROPERTIES FOLDER "godot-cpp")
-
     ### Platform is derived from the toolchain target
     # See GeneratorExpressions PLATFORM_ID and CMAKE_SYSTEM_NAME
     string(
@@ -310,7 +318,7 @@ function(godotcpp_generate)
     set(IS_DEV_BUILD "$<BOOL:${GODOTCPP_DEV_BUILD}>")
 
     ### Define our godot-cpp library targets
-    foreach(TARGET_ALIAS template_debug template_release editor)
+    foreach(TARGET_ALIAS ${GODOTCPP_TARGETS})
         set(TARGET_NAME "godot-cpp.${TARGET_ALIAS}")
 
         # Generator Expressions that rely on the target

test/CMakeLists.txt

@@ -10,7 +10,11 @@ message(STATUS "Testing Integration targets are enabled.")
 # Generate Doc Data
 file(GLOB_RECURSE DOC_XML LIST_DIRECTORIES NO CONFIGURE_DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/doc_classes/*.xml")
 
-foreach(TARGET_ALIAS template_debug template_release editor)
+set(DOC_SOURCE_FILE "${CMAKE_CURRENT_BINARY_DIR}/gen/doc_source.cpp")
+
+generate_doc_source( doc_gen "${DOC_SOURCE_FILE}" ${DOC_XML} )
+
+foreach(TARGET_ALIAS ${GODOTCPP_TARGETS})
     set(TARGET_NAME "godot-cpp.test.${TARGET_ALIAS}")
 
     add_library(${TARGET_NAME} SHARED EXCLUDE_FROM_ALL)
@@ -22,7 +26,7 @@ foreach(TARGET_ALIAS template_debug template_release editor)
 
     # conditionally add doc data to compile output
     if(TARGET_ALIAS MATCHES "editor|template_debug")
-        target_doc_sources( ${TARGET_NAME} ${DOC_XML} )
+        target_sources(${TARGET_NAME} PRIVATE "${DOC_SOURCE_FILE}")
     endif()
 
     set(OUTPUT_DIR "${CMAKE_CURRENT_SOURCE_DIR}/project/bin/")