Enhance cross-platform compatibility for loading PySRRegressor models

pysr/sr.py

@@ -51,7 +51,9 @@
 from .utils import (
     ArrayLike,
     PathLike,
+    _CrossPlatformPathUnpickler,
     _csv_filename_to_pkl_filename,
+    _path_to_str,
     _preprocess_julia_floats,
     _safe_check_feature_names_in,
     _subscriptify,
@@ -1007,11 +1009,10 @@ def from_file(
             assert unary_operators is None
             assert n_features_in is None
             with open(pkl_filename, "rb") as f:
-                model = pkl.load(f)
-            # Change equation_file_ to be in the same dir as the pickle file
-            base_dir = os.path.dirname(pkl_filename)
-            base_equation_file = os.path.basename(model.equation_file_)
-            model.equation_file_ = os.path.join(base_dir, base_equation_file)
+                unpickler = _CrossPlatformPathUnpickler(f)
+                model = unpickler.load()
+            # Convert equation_file_ to string to ensure cross-platform compatibility
+            model.equation_file_ = _path_to_str(model.equation_file_)
 
             # Update any parameters if necessary, such as
             # extra_sympy_mappings:

pysr/utils.py

@@ -1,8 +1,9 @@
 import difflib
 import inspect
 import os
+import pickle as pkl
 import re
-from pathlib import Path
+from pathlib import Path, PurePosixPath, PureWindowsPath
 from typing import Any, List, TypeVar, Union
 
 from numpy import ndarray
@@ -73,3 +74,19 @@ def _suggest_keywords(cls, k: str) -> List[str]:
     ]
     suggestions = difflib.get_close_matches(k, valid_keywords, n=3)
     return suggestions
+
+
+class _CrossPlatformPathUnpickler(pkl.Unpickler):
+    def find_class(self, module, name):
+        if module == "pathlib":
+            if name == "PosixPath":
+                return PurePosixPath
+            elif name == "WindowsPath":
+                return PureWindowsPath
+        return super().find_class(module, name)
+
+
+def _path_to_str(path):
+    if isinstance(path, (PurePosixPath, PureWindowsPath)):
+        return str(path)
+    return path