approach with no scons argument

Author: Togira123

SConstruct

@@ -19,6 +19,14 @@ except Exception:
 
 env.PrependENVPath("PATH", os.getenv("PATH"))
 
+try:
+    Import("binding_hooks")
+except Exception:
+    # binding_hooks was not exported by the user's env
+    binding_hooks = None
+
+env["binding_hooks"] = binding_hooks
+
 # Custom options and profile flags.
 customs = ["custom.py"]
 try:

binding_generator.py

@@ -1,8 +1,10 @@
 #!/usr/bin/env python
 
+import importlib.util
 import json
 import re
 import shutil
+import sys
 from pathlib import Path
 
 from make_interface_header import generate_gdextension_interface_header
@@ -284,12 +286,34 @@ def print_file_list(api_filepath, output_dir, headers=False, sources=False):
 
 
 def generate_bindings(
-    api_filepath, interface_filepath, use_template_get_node, bits="64", precision="single", output_dir="."
+    api_filepath,
+    interface_filepath,
+    use_template_get_node,
+    bits="64",
+    precision="single",
+    output_dir=".",
+    hooks_path=None,
 ):
     api = {}
     with open(api_filepath, encoding="utf-8") as api_file:
         api = json.load(api_file)
-    _generate_bindings(api, api_filepath, interface_filepath, use_template_get_node, bits, precision, output_dir)
+    custom_hooks = None
+    if hooks_path:
+        # load the file dynamically
+        try:
+            spec = importlib.util.spec_from_file_location("custom_binding_generator_hooks", hooks_path)
+            loaded_module = importlib.util.module_from_spec(spec)
+            sys.modules["custom_binding_generator_hooks"] = loaded_module
+            spec.loader.exec_module(loaded_module)
+            # assume the class is named 'CustomBindingGeneratorHooks'
+            custom_hooks = loaded_module.CustomBindingGeneratorHooks()
+        except Exception:
+            raise Exception(
+                "Failed to load custom binding generator hooks. Make sure your path points to a python file which defines a class named 'BindingGeneratorHooks'"
+            )
+    _generate_bindings(
+        api, api_filepath, interface_filepath, use_template_get_node, bits, precision, output_dir, custom_hooks
+    )
 
 
 def _generate_bindings(

cmake/GodotCPPModule.cmake

@@ -91,6 +91,7 @@ function(
     BITS
     PRECISION
     OUTPUT_DIR
+    BINDING_HOOK_FILE
 )
     # This code snippet will be squashed into a single line
     set(PYTHON_SCRIPT
@@ -101,7 +102,8 @@ function(
     use_template_get_node='${USE_TEMPLATE_GET_NODE}',
     bits='${BITS}',
     precision='${PRECISION}',
-    output_dir='${OUTPUT_DIR}')"
+    output_dir='${OUTPUT_DIR}',
+    hooks_path='${BINDING_HOOK_FILE}')"
     )
 
     message(DEBUG "Python:\n${PYTHON_SCRIPT}")

cmake/godotcpp.cmake

@@ -145,6 +145,12 @@ function(godotcpp_options)
         "Path to a custom GDExtension API JSON file (takes precedence over `GODOTCPP_GDEXTENSION_DIR` and `GODOTCPP_API_VERSION`) ( /path/to/custom_api_file )"
     )
 
+    set(GODOTCPP_BINDING_HOOK_FILE
+        ""
+        CACHE FILEPATH
+        "Path to a Python file defining custom binding generator hooks. The file has to contain a class named `CustomBindingGeneratorHooks`"
+    )
+
     #TODO generate_bindings
 
     option(GODOTCPP_GENERATE_TEMPLATE_GET_NODE "Generate a template version of the Node class's get_node. (ON|OFF)" ON)
@@ -309,6 +315,7 @@ function(godotcpp_generate)
             "${BITS}"
             "${GODOTCPP_PRECISION}"
             "${CMAKE_CURRENT_BINARY_DIR}"
+            "${GODOTCPP_BINDING_HOOK_FILE}"
     )
 
     ### Platform is derived from the toolchain target

custom_generator.py

@@ -1,4 +1,3 @@
-import importlib.util
 import os
 import platform
 import sys
@@ -14,7 +13,6 @@
 from SCons.Variables.BoolVariable import _text2bool
 
 from binding_generator import _generate_bindings, _get_file_list, get_file_list
-from binding_generator_hooks import BindingGeneratorHooks
 from build_profile import generate_trimmed_api
 from doc_source_generator import scons_generate_doc_source
 
@@ -166,16 +164,7 @@ def scons_generate_bindings(target, source, env):
 
     api = generate_trimmed_api(str(source[0]), profile_filepath)
 
-    custom_hooks: BindingGeneratorHooks = None
-    if "binding_hook_file" in env:
-        binding_hook_file = env["binding_hook_file"]
-        # yes apparently this is how you import a file dynamically ._.
-        spec = importlib.util.spec_from_file_location("custom_binding_generator", binding_hook_file)
-        loaded_module = importlib.util.module_from_spec(spec)
-        sys.modules["custom_binding_generator"] = loaded_module
-        spec.loader.exec_module(loaded_module)
-        # assume the name 'BindingGeneratorHooksExtension' for the class
-        custom_hooks = loaded_module.BindingGeneratorHooksExtension()
+    binding_hooks = env.get("binding_hooks", None)
 
     _generate_bindings(
         api,
@@ -185,7 +174,7 @@ def scons_generate_bindings(target, source, env):
         "32" if "32" in env["arch"] else "64",
         env["precision"],
         env["godot_cpp_gen_dir"],
-        custom_hooks,
+        binding_hooks,
     )
     return None
 
@@ -244,15 +233,6 @@ def options(opts, env):
     else:
         raise ValueError("Could not detect platform automatically, please specify with platform=<platform>")
 
-    opts.Add(
-        PathVariable(
-            key="binding_hook_file",
-            help="Path to python file containing custom binding generator hooks",
-            default=env.get("binding_hook_file", None),
-            validator=validate_file,
-        )
-    )
-
     opts.Add(
         PathVariable(
             key="custom_tools",