[test] fix build for macos

Author: Ghua8088

pytron/engines/native/build.py

@@ -97,53 +97,16 @@ def build():
     except Exception as e:
         print(f"[WARNING] Could not apply symbol shield: {e}")
 
-    # --- macOS: inject Python lib so the linker can resolve _Py* symbols ---
-    # Raw `cargo rustc` does not ask the Python interpreter where its dylib
-    # lives the way `maturin` does. We do it manually here.
+    # --- macOS: tell pyo3's build script which Python interpreter to use ---
+    # Setting PYO3_PYTHON is sufficient. pyo3's `extension-module` feature
+    # automatically emits `-undefined dynamic_lookup` on macOS so all _Py*
+    # symbols resolve at runtime from the embedding interpreter.
+    # Do NOT add manual -l or RUSTFLAGS: macOS framework Python's LDLIBRARY
+    # is a path ("Python.framework/Versions/3.11/Python"), not a valid -l name.
     if sys.platform == "darwin" and not is_android:
-        try:
-            import sysconfig
-
-            py_exec = sys.executable
-            # Tell pyo3's build script which Python to use
-            env["PYO3_PYTHON"] = py_exec
-
-            # Locate the Python library directory and dylib
-            ldlibdir = sysconfig.get_config_var("LIBDIR") or ""
-            ldlib = sysconfig.get_config_var("LDLIBRARY") or ""
-            multiarch = sysconfig.get_config_var("MULTIARCH") or ""
-
-            # Also check the framework path (standard macOS CPython installs)
-            framework_prefix = sysconfig.get_config_var("PYTHONFRAMEWORKPREFIX") or ""
-            framework_dir = (
-                os.path.join(framework_prefix, "lib") if framework_prefix else ""
-            )
-
-            # Build a list of candidate library search directories
-            lib_dirs = [d for d in [ldlibdir, framework_dir] if d and os.path.isdir(d)]
-
-            if lib_dirs:
-                rustflags = env.get("RUSTFLAGS", "")
-                for lib_dir in lib_dirs:
-                    rustflags += f" -L {lib_dir}"
-                # Link the Python shared library explicitly
-                if ldlib:
-                    # Strip lib prefix and extension for -l flag
-                    libname = ldlib
-                    if libname.startswith("lib"):
-                        libname = libname[3:]
-                    for ext in [".dylib", ".so", ".a"]:
-                        if libname.endswith(ext):
-                            libname = libname[: -len(ext)]
-                            break
-                    rustflags += f" -l {libname}"
-                env["RUSTFLAGS"] = rustflags.strip()
-                print(f"[INFO] macOS Python lib dirs: {lib_dirs}")
-                print(f"[INFO] RUSTFLAGS set to: {env['RUSTFLAGS']}")
-            else:
-                print(f"[WARNING] Could not locate Python library directory on macOS.")
-        except Exception as e:
-            print(f"[WARNING] macOS Python lib detection failed: {e}")
+        env["PYO3_PYTHON"] = sys.executable
+        print(f"[INFO] macOS: PYO3_PYTHON set to {sys.executable}")
+
 
     try:
         subprocess.check_call(cargo_cmd, cwd=ENGINE_DIR, env=env)