Pack STM32WL Companion help while retaining every command

scripts/nrf52_flash_trim.py

@@ -208,7 +208,7 @@ def compile_packed_help(build_env, node):
                     if not str(value).startswith("-std=")]
              for name in ("CCFLAGS", "CXXFLAGS")}
     flags["CXXFLAGS"].append("-std=gnu++17")
-    print("nRF52 Companion help: isolated C++17 source")
+    print("Companion help: isolated C++17 source")
     # Builder overrides stay attached to this object even when PlatformIO
     # collects it through the parent construction environment afterward.
     return build_env.Object(node, **flags)

scripts/stm32_companion_help.py

@@ -0,0 +1,39 @@
+"""Compile only the selected small STM32WL Companion help producer as C++17.
+
+All source selection and object overrides are reused without installing any
+nRF52 trim, changing a global language standard or changing feature defines.
+The C++ producer itself checks the final platform and terminal capabilities.
+"""
+
+import importlib.util
+from pathlib import Path
+
+
+SCRIPT_DIR = Path(__file__).resolve().parent if "__file__" in globals() else Path("scripts").resolve()
+SPEC = importlib.util.spec_from_file_location("stm32_help_source_policy", SCRIPT_DIR / "nrf52_flash_trim.py")
+POLICY = importlib.util.module_from_spec(SPEC)
+SPEC.loader.exec_module(POLICY)
+COMPANION_SOURCES = ("../examples/companion_radio/main.cpp",
+                     "../examples/companion_radio/MyMesh.cpp")
+
+
+def packed_help_policy(platform, mcu, src_filter):
+    if platform != "ststm32" or not str(mcu).lower().startswith("stm32wl"):
+        return False
+    return (all(POLICY.source_selected(src_filter, source) for source in COMPANION_SOURCES)
+            and not any(POLICY.source_selected(src_filter, source)
+                        for source in POLICY.ROLE_SOURCES + POLICY.COMPANION_SOURCES[1:]))
+
+
+def install(build_env):
+    source_filter = build_env.get("SRC_FILTER")
+    if source_filter is None:
+        source_filter = build_env.GetProjectOption("build_src_filter", "")
+    if packed_help_policy(build_env.PioPlatform().name,
+                          build_env.BoardConfig().get("build.mcu", ""), source_filter):
+        build_env.AddBuildMiddleware(POLICY.compile_packed_help, "*CompanionHelpPacked.cpp")
+
+
+if "Import" in globals():
+    Import("env")
+    install(env)