fix py13 import bug

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pyfixest_core"
-version = "0.50.0"
+version = "0.50.1"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

docs/changelog.qmd

@@ -15,7 +15,13 @@ fit2 = pf.feols("Y ~ X1 + X2", data = df)
 fit3 = pf.feols("Y ~ X1 + X2 | f1", data = df)
 ```
 
-## PyFixest 0.50.0 (In Development)
+## PyFixest 0.50.1
+
+### Bug Fixes
+
+- Fixes an import-time failure on Python 3.13 in some environments where a `narwhals` typing alias was exposed as a string at runtime. This could cause imports of `feols()` / `feglm()` to fail before any model code ran. See [#1263](https://github.com/py-econometrics/pyfixest/issues/1263) for details.
+
+## PyFixest 0.50.0
 
 ::: {.callout-tip}
 You can install the latest pre-release to try out the new features:

pyfixest/estimation/FixestMulti_.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import functools
 from collections.abc import Mapping
 from importlib import import_module

pyfixest/estimation/api/feglm.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from collections.abc import Mapping
 from typing import Any
 

pyfixest/estimation/api/feols.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from collections.abc import Mapping
 from typing import Any
 

pyfixest/estimation/api/fepois.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from collections.abc import Mapping
 from typing import Any
 

pyfixest/estimation/api/quantreg.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from collections.abc import Mapping
 from typing import Any
 

pyfixest/estimation/api/utils.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import pandas as pd
 
 from pyfixest.utils.dev_utils import DataFrameType, _narwhals_to_pandas

pyfixest/estimation/models/feglm_.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from abc import ABC, abstractmethod
 from collections.abc import Mapping
 from typing import Any, Literal

pyfixest/estimation/models/feols_.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import re
 import warnings
 from collections.abc import Callable, Mapping
@@ -580,7 +582,7 @@ def vcov(
         vcov: str | dict[str, str],
         vcov_kwargs: dict[str, str | int] | None = None,
         data: DataFrameType | None = None,
-    ) -> "Feols":
+    ) -> Feols:
         """
         Compute covariance matrices for an estimated regression model.
 

pyfixest/estimation/models/feols_compressed_.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import logging
 from collections.abc import Mapping
 from dataclasses import dataclass

pyfixest/estimation/models/fepois_.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import re
 import warnings
 from collections.abc import Mapping

pyfixest/estimation/post_estimation/prediction.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import re
 import warnings
 from collections.abc import Mapping

pyfixest/estimation/quantreg/QuantregMulti.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import gc
 import inspect
 from collections.abc import Mapping

tests/test_import_annotations.py

@@ -0,0 +1,34 @@
+import subprocess
+import sys
+import textwrap
+from pathlib import Path
+
+
+def test_stringified_dataframe_type_does_not_break_model_import():
+    repo_root = Path(__file__).resolve().parents[1]
+    script = textwrap.dedent(
+        f"""
+        import importlib
+        import sys
+
+        sys.path.insert(0, {str(repo_root)!r})
+
+        import pyfixest.utils.dev_utils as dev_utils
+
+        # Reproduce the older narwhals behavior reported in issue #1263, where
+        # the imported typing alias behaved like a string at runtime.
+        dev_utils.DataFrameType = "IntoDataFrame"
+
+        importlib.import_module("pyfixest.estimation.models.feglm_")
+        """
+    )
+
+    result = subprocess.run(
+        [sys.executable, "-c", script],
+        capture_output=True,
+        text=True,
+        cwd=repo_root,
+        check=False,
+    )
+
+    assert result.returncode == 0, result.stderr or result.stdout