add test for get_dynamic_lib_location

py-polars/polars/_utils/udfs.py

@@ -978,4 +978,21 @@ def warn_on_inefficient_map(
             )
 
 
-__all__ = ["BytecodeParser", "warn_on_inefficient_map"]
+def get_dynamic_lib_location(package_init_path: str | Path) -> str:
+    """Get location of dynamic library file."""
+    if Path(package_init_path).is_file():
+        package_dir = Path(package_init_path).parent
+    else:
+        package_dir = Path(package_init_path)
+    for path in package_dir.iterdir():
+        if _is_shared_lib(path):
+            return str(path)
+    msg = f"no dynamic library found in {package_dir}"
+    raise FileNotFoundError(msg)
+
+
+def _is_shared_lib(file: Path) -> bool:
+    return file.name.endswith((".so", ".dll", ".pyd"))
+
+
+__all__ = ["BytecodeParser", "warn_on_inefficient_map", "get_dynamic_lib_location"]

py-polars/polars/expr/expr.py

@@ -9638,7 +9638,7 @@ def register_plugin(
         changes_length: bool = False,
     ) -> Self:
         """
-        Register a shared library as a plugin.
+        Register a dynamic library as a plugin.
 
         .. warning::
             This is highly unsafe as this will call the C function

py-polars/polars/plugins.py

@@ -1,36 +1,21 @@
 from __future__ import annotations
 
-from pathlib import Path
 from typing import TYPE_CHECKING, Any
 
 from polars._utils.parse_expr_input import parse_as_list_of_expressions
+from polars._utils.udfs import get_dynamic_lib_location
 from polars._utils.unstable import unstable
 from polars._utils.wrap import wrap_expr
 
 if TYPE_CHECKING:
+    from pathlib import Path
+
     from polars import Expr
     from polars.type_aliases import IntoExpr
 
 __all__ = ["register_plugin"]
 
 
-def _get_shared_lib_location(package_init_path: str | Path) -> str:
-    """Get location of dynamic library file."""
-    if Path(package_init_path).is_file():
-        package_dir = Path(package_init_path).parent
-    else:
-        package_dir = Path(package_init_path)
-    for path in package_dir.iterdir():
-        if _is_shared_lib(path):
-            return str(path)
-    msg = f"No shared library found in {package_dir}"
-    raise FileNotFoundError(msg)
-
-
-def _is_shared_lib(file: Path) -> bool:
-    return file.name.endswith((".so", ".dll", ".pyd"))
-
-
 @unstable()
 def register_plugin(
     *args: IntoExpr | list[IntoExpr],
@@ -45,7 +30,7 @@ def register_plugin(
     changes_length: bool = False,
 ) -> Expr:
     """
-    Register a shared library as a plugin.
+    Register a dynamic library as a plugin.
 
     .. warning::
         This is highly unsafe as this will call the C function
@@ -109,7 +94,7 @@ def register_plugin(
         # Choose the highest protocol supported by https://docs.rs/serde-pickle/latest/serde_pickle/
         serialized_kwargs = pickle.dumps(kwargs, protocol=5)
 
-    lib_location = _get_shared_lib_location(plugin_location)
+    lib_location = get_dynamic_lib_location(plugin_location)
 
     return wrap_expr(
         pyexprs[0].register_plugin(

py-polars/polars/utils/udfs.py

@@ -11,7 +11,10 @@
 def _get_shared_lib_location(main_file: Any) -> str:
     issue_deprecation_warning(
         "polars.utils will be made private in a future release. Please use "
-        "`from polars.plugins import get_shared_lib_location` instead.",
+        "`from polars.plugins import register_plugin` instead. "
+        "Note that its interface has changed - check the user guide "
+        "(https://docs.pola.rs/user-guide/expressions/plugins) "
+        "for the currently-recommended way to register a plugin.",
         version="0.20.14",
     )
     directory = os.path.dirname(main_file)  # noqa: PTH120

py-polars/tests/unit/utils/test_utils.py

@@ -14,6 +14,7 @@
     time_to_int,
     timedelta_to_int,
 )
+from polars._utils.udfs import get_dynamic_lib_location
 from polars._utils.various import (
     _in_notebook,
     is_bool_sequence,
@@ -26,6 +27,8 @@
 from polars.io._utils import _looks_like_url
 
 if TYPE_CHECKING:
+    from pathlib import Path
+
     from zoneinfo import ZoneInfo
 
     from polars.type_aliases import TimeUnit
@@ -310,3 +313,24 @@ def test_is_str_sequence_check(
 )
 def test_looks_like_url(url: str, result: bool) -> None:
     assert _looks_like_url(url) == result
+
+
+def test_get_dynamic_lib_location(tmpdir: Path) -> None:
+    (tmpdir / "lib1.so").write_text("", encoding="utf-8")
+    (tmpdir / "__init__.py").write_text("", encoding="utf-8")
+    result = get_dynamic_lib_location(tmpdir)
+    assert result == str(tmpdir / "lib1.so")
+    result = get_dynamic_lib_location(tmpdir / "__init__.py")
+    assert result == str(tmpdir / "lib1.so")
+    result = get_dynamic_lib_location(str(tmpdir))
+    assert result == str(tmpdir / "lib1.so")
+    result = get_dynamic_lib_location(str(tmpdir / "__init__.py"))
+    assert result == str(tmpdir / "lib1.so")
+
+
+def test_get_dynamic_lib_location_raises(tmpdir: Path) -> None:
+    (tmpdir / "__init__.py").write_text("", encoding="utf-8")
+    with pytest.raises(FileNotFoundError, match="no dynamic library found"):
+        get_dynamic_lib_location(tmpdir)
+    with pytest.raises(FileNotFoundError, match="no dynamic library found"):
+        get_dynamic_lib_location(tmpdir / "__init__.py")