pythongh-122044: Don't error during gitignore filtering with no files (pythonGH-122045)

sethmlarson · miss-islington · commit 7e51e8fac895 · 2024-07-27T14:09:51.000Z
(cherry picked from commit 4e04d1a) Co-authored-by: Seth Michael Larson <seth@python.org>
diff --git a/Tools/build/generate_sbom.py b/Tools/build/generate_sbom.py
@@ -108,6 +108,10 @@ def filter_gitignored_paths(paths: list[str]) -> list[str]:
 
         '.gitignore:9:*.a    Tools/lib.a'
     """
+    # No paths means no filtering to be done.
+    if not paths:
+        return []
+
     # Filter out files in gitignore.
     # Non-matching files show up as '::<whitespace><path>'
     git_check_ignore_proc = subprocess.run(
