Add optional Distribution parameter to walk_revctrl file finder

setuptools/command/egg_info.py

@@ -582,7 +582,7 @@ def add_defaults(self) -> None:
         sdist.add_defaults(self)
         self.filelist.append(self.template)
         self.filelist.append(self.manifest)
-        rcfiles = list(walk_revctrl())
+        rcfiles = list(walk_revctrl(distribution=self.distribution))
         if rcfiles:
             self.filelist.extend(rcfiles)
         elif os.path.exists(self.manifest):

setuptools/command/sdist.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import contextlib
+import inspect
 import os
 import re
 from collections.abc import Iterator
@@ -17,10 +18,47 @@
 _default_revctrl = list
 
 
-def walk_revctrl(dirname='') -> Iterator:
+def _call_finder_with_distribution_support(finder_func, dirname='', distribution=None):
+    """
+    Call a file finder function with distribution support if available.
+
+    This helper function inspects the finder function's signature to determine
+    if it accepts a distribution parameter. If it does, the distribution is passed;
+    otherwise, only the dirname is passed for backward compatibility.
+
+    Args:
+        finder_func: The file finder function to call
+        dirname: Directory name to search (default: '')
+        distribution: Distribution object to pass if supported (default: None)
+
+    Returns:
+        Iterator of file paths from the finder function
+
+    Raises:
+        Any exception raised by the finder function itself
+    """
+    try:
+        sig = inspect.signature(finder_func)
+        params = list(sig.parameters.keys())
+
+        # If function accepts distribution parameter, pass it
+        if len(params) > 1 and 'distribution' in params:
+            return finder_func(dirname, distribution=distribution)
+        else:
+            # Fall back to dirname-only for backward compatibility
+            return finder_func(dirname)
+    except (ValueError, TypeError):
+        # If signature inspection fails, fall back to dirname-only
+        return finder_func(dirname)
+
+
+def walk_revctrl(dirname='', distribution=None) -> Iterator:
     """Find all files under revision control"""
     for ep in metadata.entry_points(group='setuptools.file_finders'):
-        yield from ep.load()(dirname)
+        finder_func = ep.load()
+        yield from _call_finder_with_distribution_support(
+            finder_func, dirname, distribution
+        )
 
 
 class sdist(orig.sdist):

setuptools/tests/test_sdist.py

@@ -19,7 +19,7 @@
 from setuptools import Command, SetuptoolsDeprecationWarning
 from setuptools._importlib import metadata
 from setuptools.command.egg_info import manifest_maker
-from setuptools.command.sdist import sdist
+from setuptools.command.sdist import _call_finder_with_distribution_support, sdist
 from setuptools.dist import Distribution
 from setuptools.extension import Extension
 from setuptools.tests import fail_on_ascii
@@ -982,3 +982,109 @@ def test_sanity_check_setuptools_own_sdist(setuptools_sdist):
     # setuptools sdist should not include the .tox folder
     tox_files = [name for name in files if ".tox" in name]
     assert len(tox_files) == 0, f"not empty {tox_files}"
+
+
+class TestCallFinderWithDistributionSupport:
+    """Tests for the _call_finder_with_distribution_support helper function"""
+
+    def test_finder_with_distribution_parameter(self):
+        """Test that finder functions accepting distribution parameter receive it"""
+
+        def finder_with_distribution(dirname, distribution=None):
+            return [f"file_in_{dirname}_with_dist_{distribution}"]
+
+        result = list(
+            _call_finder_with_distribution_support(
+                finder_with_distribution, dirname="testdir", distribution="test_dist"
+            )
+        )
+
+        assert result == ["file_in_testdir_with_dist_test_dist"]
+
+    def test_finder_without_distribution_parameter(self):
+        """Test that finder functions not accepting distribution parameter work normally"""
+
+        def finder_without_distribution(dirname):
+            return [f"file_in_{dirname}"]
+
+        result = list(
+            _call_finder_with_distribution_support(
+                finder_without_distribution, dirname="testdir", distribution="test_dist"
+            )
+        )
+
+        assert result == ["file_in_testdir"]
+
+    def test_finder_with_single_parameter_only(self):
+        """Test that finder functions with only dirname parameter work"""
+
+        def finder_single_param(dirname):
+            return [f"single_{dirname}"]
+
+        result = list(
+            _call_finder_with_distribution_support(finder_single_param, dirname="test")
+        )
+
+        assert result == ["single_test"]
+
+    def test_finder_with_distribution_named_differently(self):
+        """Test that only functions with 'distribution' parameter name get it"""
+
+        def finder_with_other_param(dirname, other_param=None):
+            return [f"other_{dirname}_{other_param}"]
+
+        # Should not pass distribution even though function has 2+ params
+        result = list(
+            _call_finder_with_distribution_support(
+                finder_with_other_param, dirname="test", distribution="dist_obj"
+            )
+        )
+
+        assert result == ["other_test_None"]
+
+    def test_finder_with_signature_inspection_failure(self):
+        """Test fallback behavior when signature inspection fails"""
+
+        # Create a mock function that raises an error during signature inspection
+        def problematic_finder(dirname):
+            return [f"fallback_{dirname}"]
+
+        # Mock inspect.signature to raise ValueError
+        with mock.patch(
+            'setuptools.command.sdist.inspect.signature',
+            side_effect=ValueError("test error"),
+        ):
+            result = list(
+                _call_finder_with_distribution_support(
+                    problematic_finder, dirname="test", distribution="dist_obj"
+                )
+            )
+
+        assert result == ["fallback_test"]
+
+    def test_finder_with_multiple_parameters_including_distribution(self):
+        """Test finder with multiple parameters where one is distribution"""
+
+        def complex_finder(dirname, extra_param=None, distribution=None):
+            return [f"complex_{dirname}_{extra_param}_{distribution}"]
+
+        result = list(
+            _call_finder_with_distribution_support(
+                complex_finder, dirname="test", distribution="dist_obj"
+            )
+        )
+
+        assert result == ["complex_test_None_dist_obj"]
+
+    def test_finder_function_raises_exception(self):
+        """Test that exceptions from finder functions are properly propagated"""
+
+        def failing_finder(dirname, distribution=None):
+            raise RuntimeError("Finder failed")
+
+        with pytest.raises(RuntimeError, match="Finder failed"):
+            list(
+                _call_finder_with_distribution_support(
+                    failing_finder, dirname="test", distribution="dist_obj"
+                )
+            )