Use pathlib.Path objects internally

It is the best practice nowadays. Paths are only converted to strings for text representation, like when logging.

piptools/scripts/compile.py

@@ -16,6 +16,7 @@
 from pip._internal.req.constructors import install_req_from_line
 from pip._internal.utils.misc import redact_auth_from_url
 
+from pathlib import Path
 from .._compat import parse_requirements
 from ..cache import DependencyCache
 from ..exceptions import NoCandidateFound, PipToolsError
@@ -356,7 +357,7 @@ def cli(
     emit_index_url: bool,
     emit_options: bool,
     unsafe_package: tuple[str, ...],
-    config: str | None,
+    config: Path | None,
 ) -> None:
     """
     Compiles requirements.txt from requirements.in, pyproject.toml, setup.cfg,
@@ -409,7 +410,7 @@ def cli(
         )
 
     if config:
-        log.info(f"Using pip-tools configuration defaults found in '{config}'.")
+        log.info(f"Using pip-tools configuration defaults found in '{config !s}'.")
 
     if resolver_name == "legacy":
         log.warning(

piptools/scripts/sync.py

@@ -14,6 +14,7 @@
 from pip._internal.metadata import get_environment
 
 from .. import sync
+from pathlib import Path
 from .._compat import parse_requirements
 from .._compat.pip_compat import Distribution
 from ..exceptions import PipToolsError
@@ -120,7 +121,7 @@ def cli(
     client_cert: str | None,
     src_files: tuple[str, ...],
     pip_args: str | None,
-    config: str | None,
+    config: Path | None,
 ) -> None:
     """Synchronize virtual environment with requirements.txt."""
     log.verbosity = verbose - quiet
@@ -146,7 +147,7 @@ def cli(
             sys.exit(2)
 
     if config:
-        log.info(f"Using pip-tools configuration defaults found in '{config}'.")
+        log.info(f"Using pip-tools configuration defaults found in '{config !s}'.")
 
     if python_executable:
         _validate_python_executable(python_executable)

piptools/utils.py

@@ -535,7 +535,7 @@ def parse_requirements_from_wheel_metadata(
 
 def callback_config_file_defaults(
     ctx: click.Context, param: click.Parameter, value: str | None
-) -> str | None:
+) -> Path | None:
     """
     Returns the path to the config file with defaults being used, or `None` if no such file is
     found.
@@ -570,7 +570,7 @@ def callback_config_file_defaults(
     defaults.update(config)
 
     ctx.default_map = defaults
-    return str(config_file)
+    return config_file
 
 
 def select_config_file(src_files: tuple[str, ...]) -> Path | None:

tests/test_utils.py

@@ -597,7 +597,7 @@ def test_callback_config_file_defaults(pyproject_param, new_default, make_config
     ctx = Context(compile_cli)
     ctx.params["src_files"] = (str(config_file),)
     found_config_file = callback_config_file_defaults(ctx, "config", None)
-    assert found_config_file == str(config_file)
+    assert found_config_file == config_file
     # Make sure the default has been updated
     lookup_param = get_click_dest_for_option(pyproject_param)
     assert ctx.default_map[lookup_param] == new_default