feat(build): Allow local configuration build options with custom.py

feat(build): Allow deleting unassociated intermediate files (on by default)
feat(build): Added recursive searching for C++ source files in src/extension
feat(git): Ignore /custom.py

Author: Spartan322

.gitignore

@@ -61,4 +61,7 @@ bin/*
 *.files
 *.includes
 *.idb
-*.exp
+*.exp
+
+# Build configuarion.
+/custom.py

SConstruct

@@ -1,9 +1,43 @@
 #!/usr/bin/env python
 import os
 import sys
+from glob import glob
+from pathlib import Path
+
+# Neccessary to have our own build options without errors
+SAVED_ARGUMENTS = ARGUMENTS.copy()
+ARGUMENTS.pop('intermediate_delete', True)
 
 env = SConscript("godot-cpp/SConstruct")
 
+ARGUMENTS = SAVED_ARGUMENTS
+
+# Custom options and profile flags.
+customs = ["custom.py"]
+profile = ARGUMENTS.get("profile", "")
+if profile:
+    if os.path.isfile(profile):
+        customs.append(profile)
+    elif os.path.isfile(profile + ".py"):
+        customs.append(profile + ".py")
+opts = Variables(customs, ARGUMENTS)
+
+opts.Add(
+    BoolVariable("intermediate_delete", "Enables automatically deleting unassociated intermediate binary files.", True)
+)
+
+opts.Update(env)
+Help(opts.GenerateHelpText(env))
+
+def GlobRecursive(pattern, node='.'):
+    import SCons
+    results = []
+    for f in Glob(str(node) + '/*', source=True):
+        if type(f) is SCons.Node.FS.Dir:
+            results += GlobRecursive(pattern, f)
+    results += Glob(str(node) + '/' + pattern, source=True)
+    return results
+
 # For the reference:
 # - CCFLAGS are compilation flags shared between C and C++
 # - CFLAGS are for C-specific compilation flags
@@ -14,7 +48,27 @@ env = SConscript("godot-cpp/SConstruct")
 
 # tweak this if you want to use different folders, or more folders, to store your source code in.
 env.Append(CPPPATH=["extension/src/"])
-sources = Glob("extension/src/*.cpp")
+sources = GlobRecursive("*.cpp", "extension/src")
+
+# Remove unassociated intermediate binary files if allowed, usually the result of a renamed or deleted source file
+if env["intermediate_delete"]:
+    def remove_extension(file : str):
+        if file.find(".") == -1: return file
+        return file[:file.rindex(".")]
+
+    found_one = False
+    for obj_file in [file[:-len(".os")] for file in glob("extension/src/*.os", recursive=True)]:
+        found = False
+        for source_file in sources:
+            if remove_extension(str(source_file)) == obj_file:
+                found = True
+                break
+        if not found:
+            if not found_one:
+                found_one = True
+                print("Unassociated intermediate files found...")
+            print("Removing "+obj_file+".os")
+            os.remove(obj_file+".os")
 
 if env["platform"] == "macos":
     library = env.SharedLibrary(